Tag Archives: AK

AKBuilds, China, Shotguns

THE LYNX 12 – POST 3 OF 3: Adding the Customizations

This is the third post in a three part series about customizing a Lynx 12 Shotgun.  In the first post, I wrote about my “out of the box” observations and in the second post, I disassembled the Lynx and also recorded observations.  In this final post, I’ll add in my planned customizations and explain my rationale for each.

Palmetto State Armory has SDS Lynx 12 gauge shotguns for sale – click here to go to their order page.

Installing the Rifle Dynamics AK to M4 Adapter

I like M4 stocks and did some digging around.  In the past, I have used Ace/Double Star and other modular adapters.  The problem with them is that unless you cut the tang off the rear trunnion, you have a rather long receiver block sticking out of your rifle and I wanted to avoid that.

I do a lot of surfing and a new style of adapter had caught my eye made by Rifle Dynamics.  They have an AK to M4 stock adapter that rides over the tang vs. behind it.  This design gets rid of the receiver block sticking out or the need to alter the rifle.  Brownells carries them. Note, the PSA adapter is almost identical.

The unit comes with clear instructions but do read the little yellow supplement they include.  After getting feedback about the angle the unit positions the buffer tube at, they added two small Delrin washers that need to be installed also.

Installation took about 10 minutes – in large part because I was snapping photos but also because I didn’t want to rush and make a mistake.

So the big L-Bracket just goes under the tang and is screwed into place.  I put Blue Loc-Tite on both screws to prevent them from loosening up.  Based on past experiences with stocks that loosened up using modular mounts, be sure to use some form of thread locker.  I did not tighten the screws down yet because I wasn’t sure if I would need to wiggle the tube adapter into place or not.

So with the L-Bracket in place, I then attached the Tube Adapter.  The Delrin washers go between the Tube Adapter and the L-Bracket.  I applied Blue Loc-Tite to these screws also.

I then tightened down all the screws and that was it.

Adding a C&H Mercury Buffer to the M4 Buffer Tube

Based on past experience with other similar firearms, I knew the Lynx would be front heavy plus I knew 12 gauge shotguns in general have a fair amount of recoil.  Both of these could be addressed by installing a C&H Mercury Recoil Suppressor.  I use the model 100785 as I know it will slide down the buffer tube of an M4 given the suppressor measures 7/8″ x 5″.  You wouldn’t use this in a normal AR because the buffer tube would have the buffer and spring inside.  However, in our case, an AK does not use the buffer tube so that means we can do whatever we want.  I ordered by unit from MPC Sports, where I have bought them in the past.

I’ve used these a number of times over the years in shotguns and rifles to add weight to the rear and to reduce the recoil.  This last part is interesting.  Basically you have a 7/8″ diameter heavy tube that is 5″ long that is hollow.  Inside it is partially filled with liquid mercury and then very tightly sealed — there is no way it is coming out.

What happens is that when the firearm is fired and the rearward motion starts, the mercury liquid sloshes in the tube.   The tube goes back and the mercury partially stays in place until it is hit by the front of the tube.  This helps to split the recoil impulse into two parts – the initial impulse and then when the mercury hits.

If you can’t afford a mercury buffer you could always fill the rear 5-6″ with bird shot and then cap it with a thick layer of epoxy.

The Mil-Spec six position buffer tube is a straight forward unit made by Expo Arms and I bought it from Primary Arms.  You will still need to get the castle nut and end plate of your choice.  Primary Arms, Brownells and Palmetto are all good places to check.  I really do not recall where I got the castle nut and end plate I used on this project – they were in a parts bin.

Installation is very simple because all you need to do is epoxy it into the buffer tube.  I would recommend scuffing the tube with a bit of sand paper so the epoxy can stick well and then spray down the supressor and the inside of the buffer tube with brake cleaner.

Not all epoxies are up to the task.  I’d recommend Brownell’s Acra-Glas liquid epoxy for this (not their gel version).  I use 10cc syringes to meter out 4 parts resin to 1 part hardener.  I mixed up and used 4 batches so 16 cc of resin and 4 cc of hardener.  Make sure you stir it completely.  The stuff has a long pot like so really mix it well.

I secured the buffer tube in my vise and made sure it was vertical.  Next, I poured a bit down in the tube first – just enough to put a thin layer at the bottom and inserted the suppressor into the tube and poured in the remaining epoxy.  It will need to sit and cure for 2-4 hours before you can handle it.  I keep an eye on the remnants in the mixing cup to see when it is hard enough to handle as the temperature will affect how long it takes.  Note – it needs to cure 24 hours to reach full strength and you’d want that before firing the weapon and subjecting the epoxy to stress.

At any rate, after pouring, wipe off any epoxy you may get on the tube.  Brake cleaner on a rag will help until it cures.  After that, it would likely require sanding to remove so be sure it is clean before you walk away.

So with that done and curing I moved on to the grip.

Installing the Ronin’s Grips AK-12 Grip

The Lynx comes with a basic pistol grip but I wanted to use one of my AK-12 grips.  These are very ergonomic and feel really good to me.  I wear an XL-size glove and both the size and angle work for me.

I replaced the small 5mm bolt with one of our 6mm alloy bolts and also used a 6mm grip nut that I had in my parts bin to secure the grip in place.

In the same manner as other AKs, the grip nut sits in the square hole behind the trigger guard and then the grip sits on the other side and the bolt pulls them together with the receiver sandwiched in the middle.

Adding a Chaos Saiga 12 Apollo 12 Extended Rail

The Lynx can use Saiga handguards so you have a lot of options.  Note that I am using a Chaos rail and Chaos has since gone out business.  The rail in question was their Apollo 12 Extended M-LOK Rail.

Installation is pretty easy.  You will need to remove the original sights though.  A small punch can be used to drift out the rear sight and either a small wrench or pliers can be used to unscrew and remove the front sight.  I’d recommend having a Zip Loc bag or something to store these parts in just in case.

Unscrew the four screws on the sides to split the rail system into its two halves.  The bottom slides into position.  Use their screw to secure the front.  Use Blue Loc-Tite on it too.   In the rear by the receiver is a set screw.  Back it out, apply Blue Loc-tite and then screw it down.  It will push on the barrel lock the handguard into position so it will not wobble.

With the base secure you can install the top half when ready.  Notice how I said that.  What I found is that the bolt carrier must be installed and the dust cover installed before you install the top half.  So, I went ahead lubricated the shotgun and closed it up before I installed the top rail.  This also brings to light that the screws will need to be removed to gain access to inside the shotgun for cleaning.  Time will tell how well that works out.  If it drives me nuts, I’ll cut the rail off flush with the gas tube seat.  Right now though, I sure like how it positions my red dot.

Lubricating the Lynx

As mentioned above, I had to install the bolt carrier assembly and dust cover to then finalize the rail.  I am doing something different with the Lynx.  A month back I started using Super Lube synthetic grease on my Uzi and it worked great.  With the Lynx having the heavy parkerization on everything, I used Superlube to grease the rails and all sliding surfaces.  I used a precision oiler with Mobil 1 5w-30 full synthetic on all of the rotating parts.  Boy did this combination make things operate smoothly!

Installing the M4 Mil-Spec Buffer Tube

By now, the buffer tube with the mercury suppressor was cured enough to be safely installed.   Basically, it is installed the same as on an AR but it is much heavier.  Thread the castle nut all the way to the end of threads, install the end plate and then screw the tube into the Rifle Dynamics stock adapter.  Note need to buy the end plate and the castle nut – they typically do not come with a buffer tube.

When you are almost out of space to screw the buffer tube because of the end plate riding in the groove, stop, push the end plate into the adapter and tighten the castle nut down using your favorite tool.

While I used the above pictured wrench, I’ve since switched to the Magpul wrench and swear by.  It’s the best wrench I’ve found for stock work including castle nuts.

In the next photo you can see that I am using a end plate with sling loops plus you can see that I staked the castle nut.  Because of the recoil of the 12 gauge, I created a small divot with a center punch – this is known as “staking”.  It will mechanically lock the castle nut in place.   I could have put Blue Loc-tite on the castle nut but I went old school.

I then used a cotton swab and some Brownells Oxpho-Blue to cold blue the bare metal to a black color and then wiped it down with WD-40.

Installing the Magpul ACS Stock with Limbsaver Pad

I like the Magpul ACS stocks.  They are comfortable, have a locking lever to keep them from wobbling and have storage compartments you can either really use for storage or fill with epoxy and bird shot to further adjust the weight and balance of a rifle.

As luck would have it, I don’t have a photo of the stock before installation but will tell you that the one challenge is to lift the locking pin.  Magpul gives you a dummy cartridge to help with this but I made a tool to hook the pin and lift easy as can be.

Now one thing that is nice with hard recoiling firearms is a decent recoil pad.  I’ve long been a fan of Limbsaver pads and they make a model specific for the Magpul ACS, ACS-L, CTR, MOE, STR and UBR.  It’s nice and thick and provides a lot of cushion especially compared to the original pad it replaces.

I purchased the Magpul ACS for Mil-Spec buffer tubes from Primary Arms and the recoil pad off Amazon.

Installing the JMac RRD-4C 12 Brake

If you want to tame recoil, a good brake is essential.  Justin McMillion and his company JMAC Customs make some great brakes so reaching out to him for a brake made perfect sense.  He recommended their RRD-4C “12” brake.

The first thing I noticed was it’s size – it’s huge and badassed looking.  Installation is a breeze.  Unscrew the thread protector from the Lynx to expose its threads.  Screw on the jam nut as far as you can and then thread on the brake as far as you can.  Back it off enough that the brake is flat and the chambers are venting up as shown below.  Then tighten the jam nut up against the back of the brake to lock it in place.

Installing the Crossfire Red Dot and American Defense Quick Release Lever

My go to red dot these days is the excellent Vortex Crossfire unit.  It’s small and only has a 2 MOA dot.  It comes configured for an AR but you can remove the tall base and use the supplied shorter one for a lower mount.  Recently, I started using American Defense bases  because they have a solid quick release lever so you can remove the red dot quickly.  The base required is the AD-T1-L STD.

You just unscrew the four little screws on the bottom  of the optic, apply Blue Loctite on the screws and attach it to the new base.  Not hard at all!  The results are totally worth it.

Caution about eBay:  Watch out for cheap counterfeit products on eBay.  I would recommend buying the optic and mount from a reputable dealer to make sure you are getting the real deal.  The cheap knock offs just do not hold up.

Streamlight TLR-2 HL G

I installed a small 5 slot Magpul M-Lok aluminum rail section on the bottom front of the handguard to hold a Streamlight TLR-2 HL G 800 lumen light and green laser.  I have found they hold up remarkably well.  In this age of cheap Chinese products, I would recommend buying a light that will work when you need it most.

To mount it, follow the directions with the light to install the key for the Picatinny rail.  It comes with several and then it just screws onto the mount with the thumbscrew,

Caution about eBay:  Watch out for cheap counterfeit products on eBay.  I would recommend buying the Streamlight from a reputable dealer to make sure you are getting the real deal.  The cheap knock offs just do not hold up.

The End Result

I am very happy with how it turned out.  The balance is great and the red dot is located just right – when I bring the shotgun up – the dot is right where I need it.  I definitely need to take it to the range and like how it turned out.  By the way, the magazine you see is the new SDS 10 round unit.

I hope you enjoyed these blog posts.  There will be more to come 🙂

Note, I have to buy all of my parts – nothing here was paid for by sponsors, etc. I do make a small amount if you click on an ad and buy something but that is it. You’re getting my real opinion on stuff.

If you find this post useful, please share the link on Facebook, with your friends, etc. Your support is much appreciated and if you have any feedback, please email me at in**@ro*********.com. Please note that for links to other websites, I may be paid via an affiliate program such as Avantlink, Impact, Amazon and eBay.

AKBuilds, China, Shotguns

The Lynx 12 – Post 2 of 3: Disassembly and Observations

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In the first post, I documented my favorable first impressions of the SDS Lynx 12 shotgun.  After posting, at least 10 gentlemen have come forward stating how much they like their Lynx 12 shotguns and nobody reported any problems.  In this post, I’ll write about taking the shotgun apart in order to install my planned customizations, which will be in the next post.

Palmetto State Armory has SDS Lynx 12 gauge shotguns for sale – click here to go to their order page.

Call me old school, but the first thing I did was to read the manual 🙂  The next thing was to hose down the hole shotgun and wipe it down to remove all the odd smelling rust preservative.  I really didn’t care for the tacky feel to be there while working on it.  Once removed, I sprayed on Rem Oil to prevent rust while I was working on it.  Rem Oil is nice and thin and doesn’t have too much of a smell.  It’s my go to for situations like this.  If you do remove the preservative, just be sure to apply whatever oil or rust inhibitor you prefer.

Removing the Dust Cover and Recoil Spring

The dust cover comes off by pushing the release latch (the little button that sticks up) on the recoil spring and pushing the whole assembly forward while lifting the dust cover up and off the receiver.

You’ll notice I have the Lynx sitting in my Tipton vise.  I’ve had it for years and it really makes working on long arms way easier.

With the dust cover off, you can get a good look at the recoil spring  assembly.  Some guys will call this the operating spring or the return spring but basically it absorbs the energy of the bolt carrier assembly coming back after firing and then when the spring has enough energy, it pushes the bolt carrier assembly forward to then cock the trigger and strip a round off the magazine and go back into battery.

Compared to a regular AKM, you will notice the release latch and the rubber buffer assembly at the rear.  I find the use of a buffer interesting.  Normally the spring should absorb the energy and my bet is that the designers put it there in case the user either adjusts the gas regulator such that the system is over-gassed and the carrier comes back with more force than the spring alone can handle or they put it there just in case of a round that generates more pressure than what the spring can handle but the gas regulator doesn’t exactly have the right setting — imagine needing a gas setting of “3.5”. At the third position there is too much gas but at 4 there is too little.  I have little doubt it is a good idea.  I’d recommend to keep a spare buffer on hand and inspect the one in the shotgun regularly.  It ought to last a long time under most conditions but the buffers are dirt cheap.

To remove it, push forward on the rear part that normally protrudes from the dust cover.  It should slide forward in the slot that holds it on the trunnion until it is free and you can then lift up and pull back to remove the assembly from the bolt carrier and shotgun overall.

You will also note that the designers made the recoil spring assembly two parts – the rear is a tube like an RPK or older milled AKs with one spring.  There is then an additional cover that rides on that rear tube and normally closes the otherwise enlarged ejection port in the dust cover.  In front of that is then a floating spring.

Removing the Bolt Carrier Assembly and Looking Inside the Receiver

First, remove the bolt carrier assembly.  It slides to the rear of the receiver and can then be lifted up out of the receiver.  Note – it must be fully to the rear or the receiver’s guide rails will retain it.

It’s interesting how the bolt carrier is short.  In the gas tube, which is pinned in place, is a disc, that some call the “gas puck” or just “puck” which is the gas piston.  Unlike an AKM, the gas tube is held in place by the gas tube seat (it reminds me of a rear sight block in a way) that would need it’s retaining pin to be punched out to be removed.  When you tilt the shotgun forward and back, you can hear the puck moving back and forth in the gas tube.  I didn’t take the gas tube assembly apart but it looks straight forward enough.

The carrier is holding a really massive bolt.  It operates very much like any AK – the bolt head has a cam that travels through a slot in the carrier that in turn rotates it into or out of battery.

By moving the bolt head to the rear, the cam can be rotates out of the slot and the bolt head then removed from the carrier.

Look at the size of the extractor!

Interestingly, the firing pin has a spring pushing it backward compared to the floating firing pins you normally find in an AK rifle.  In this photo you can see the tail of the firing pin pushed out the back of the bolt body by the spring.

Looking down in the receiver was a very typical looking fire control group.  Note, it has been tweaked slightly to work in a Saiga or Lynx so if you want to replace the fire control group you will need to either buy one made for the the Saiga or Lynx or you will need to make some modifications.

Normally I replace the fire control group (FCG) with a US made set but the Lynx’s trigger is surprisingly decent.  Not great, but decent.  It was gritty from the parkerizing and lack of use but I figured grease and time could cure that.  I may well swap it out in the future but time will tell.

The Pistol Grip

Now I did run into one surprise that I did not expect – see the grip nut below?  I figured it would be a regular AKM nut meaning threaded for a 6mm diameter x 1.0mm pitch screw.  It’s not.  I did not expect this but the grip screw is actually smaller than an AK’s.  The screw is actually 5mm diameter x 106mm long.  I did not bother finding out the pitch by the way because it would not be staying!  Instead, I focused on the hole in the receiver – it was the same size as a normal AKM grip nut.  Whew – Problem solved.  I would replace it  with a beefier AKM nut and one of our high-strength alloy grip screws (I’ll detail that in the next post).

To remove the grip, there is a blade screw head on the base.  Simply unscrew it and remove the grip and the grip nut.

Removing the Buttstock

The plastic buttstock is held in place by two machine screws on the top of the rear trunnion.  The rear trunnion is an AK-74 forked style with the front portion open.  The stock with its lightning cuts on the side harks to the 74 also other than having a recoil pad thicker than what you would find on a 74.

Given how front heavy the shotgun felt, I was not surprised to find out that the buttstock was actually hollow.  The Chinese installed threaded inserts for strength.  I think that is commendable actually.  The fit of the buttstock to the receiver is both well done and very tight.  This is what will bear the recoil – the screws are just there to hold it together.

Because of the tight fit, I secured the rifle in my vise after removing the selector lever.  I then used a wood dowel and hammer to tap on the lip of the stock to push it backwards out of the receiver.  It really didn’t take much force to get it out.  For those of you who have tried to get an old varnished AK-47 stock out of a receiver, you know exactly what I mean and the Lynx requires just a small fraction of that.

The Forearm

The sporting looking forearm is held in place by a 5mm diameter x 11mm long screw.  Unscrew it and push the handguard forward past the gas tube and then pull it off the barrel.  Mine was a tight fit so I did need to pull it off the barrel and not just lift.  I did use a small piece of wood and a hammer to get it started out of the receiver.

Done

At this point, I had the shotgun all the way apart other than the muzzle cap.  I left that on to protect the threads while I worked.  The next blog post will detail the customizations and a few surprises that happened along the way.

If you find this post useful, please share the link on Facebook, with your friends, etc. Your support is much appreciated and if you have any feedback, please email me at in**@ro*********.com. Please note that for links to other websites, I may be paid via an affiliate program such as Avantlink, Impact, Amazon and eBay.

AKBuilds, China, Shotguns

The Lynx 12 – Post 1 of 3: Unboxing and First Impressions

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For some reason, I never really got into the Saigas when they were the hot conversion ticket. I guess it was because I was mainly working on rifles and had a Vepr 12. At any rate, when I heard from Paul Popov that SDS was importing a Saiga-12 clone known as the Lynx 12 from China where it was made in the same factory that made the Type 56 AKs.  Even better, it did not need the conversion and the street price was about $499, I contacted Scott Igert, my friend who owns Modern Antique Firearms in Benton Harbor, MI, to order me one.

Palmetto State Armory has SDS Lynx 12 gauge shotguns for sale – click here to go to their order page.

In short order the shotgun arrived and then promptly sat idle as I was busy with a ton of other projects. Scott nudged me along to take a look as he was curious about the Lynx 12 also as were clients of his. That prompted me to get my act in gear and take a close look at the shotgun by taking it apart to install a bunch of modifications I had planned.

The first step was to give it a careful external exam. The Lynx had a nice heavy uniform dark parkerized finish – probably a manganese “park” given the color.  There was some type of preservative on it that had the most interesting smell.  I have no way to describe it other that to say it did not smell like the typical cosmoline-ish anti-corrosion coatings I was used to.  Note, parkerization does not prevent rust but what it does do is create a textured surface that oil, preservatives or even weapons finishes can “grab” hold of an stay in place.  For example, when I build an AK, I have found that abrasive blasting, followed by manganese parkerization and then Norrell’s Molyresin is a remarkably durable finishing process.  By the way, I have a post on how to do make and apply your own manganese parkerization.

The rivets were pretty good – in a few cases the domes were flatter than others, which is me nit picking, but they all were sitting nice and snug against the sheet metal.  Rivets are pretty amazing and result in strong attachments of the forged trunnions to the sheet metal as long as they are formed properly and the Lynx’s rivets are solid.

I found it interesting that the front trunnion sits on top of the sheet metal receiver.  The fitment was pretty good.

There were reports of early models having sharp edges but I did not see any.  All edges and the parkerized finish were well done.

I did notice that the rear stock screw as a bit chewed up by whomever installed the rear stock.  Normally you see this when someone uses a screw driver blade that is too small.  Not too bad and since I planned on replacing the rear stock, I really wasn’t worried about it.

The selector lever was noticeably loose.  On most AK rifles, it takes a bit of effort to move the lever between the safe and fire positions.  The lever on the Lynx moves very easily.  I’ll bend the lever slightly or use a center punch to increase the depth of the detent.  Again, not a big worry.

Because the shotgun is brand new and the fire control group and the inside of the receiver are all parkerized, the action was pretty rough.  This was to be expected – the parts need to wear in.  I knew from experience that cleaning and better lubrication would help.

The muzzle cover was easy to remove and threaded nicely.  It is threaded to use Saiga chokes and brakes.

The dust cover has an additional retainer spring and pin that you do not see on most AKMs to hold the dust cover in place.  Notice the attention to detail that the retaining button is shaped to allow the dust cover to clear it better.

A nicely done optics side rail is already installed and begging to be used.

It’s a good thing that is there because I really think you will want to run a red dot either via a scope mount or on a front rail.  The Lynx’s sights are to the front and rear of the gas tube.  The rear has a dovetail and can be drifted with a pin punch to the left or right.  The front sight is threaded and can be adjusted up or down.  They definitely are functional but I don’t care for them at all to be perfectly honest.

The gas regulator is pretty slick and how has four settings for you to choose from.  The SDS website describes the settings thusly:

…smallest dot = basically no gas, no rounds will usually cycle when the regulator is on this position. Next smallest dot = “00” buckshot, high velocity rounds and slugs. Next to largest dot = all things in between your results and field testing will be required to see what your individual shotgun will run in this setting. Largest dot = birdshot and other lower powered ammunition.

You’ll notice it has an AK-74 looking buttstock but it is actually hollow and very light.  It’s nicely formed and installed but the net result is that the shotgun is light overall but very front-heavy.  I planned to replace the buttstock, grip and forearm from the start and I will describe what was one and why in future posts in this series.

It uses Saiga magazines also.  One five round mag comes with the shotgun and SDS now sells 10 round magazines also that you can readily find.  It’s actually harder to find spare five round SDS-brand magazines right now than the 10 round units.

By the way, if you are interested about how it shoots, I haven’t had a chance to take it out yet.  In researching the shotgun and how durable it was, I talked to Paul Popov and he has 350 rounds through his with no signs of trouble.  I also talked to Justin McMillion at JMAC Customs and they have put through about 500 rounds also with no problems showing up.  Here is a great overview video from Justin and his wife Ashley:

To sum it all up, I was pretty impressed with my initial just out of the box assessment.  I’m certainly not done though as I bought the Lynx specifically to customize and blog about.  The custom Lynx 12 blog series will have two more posts – one about disassembly and then one with the customizations I made.

If you find this post useful, please share the link on Facebook, with your friends, etc. Your support is much appreciated and if you have any feedback, please email me at in**@ro*********.com. Please note that for links to other websites, I may be paid via an affiliate program such as Avantlink, Impact, Amazon and eBay.

Poland

Assembling A Beryl-ish AK From A WBP Kit – Part 8 – Installing the Furniture, Muzzle Brake, Red Dot Optic and Test Firing

So here we are at the end. All that was left was to install the buttstock, handguards, muzzle brake, optic and test fire the rifle.

Beryl Furniture

The Poles evolved the Beryl furniture over the years so I went with a particular handguard from Robert RTG that I liked, buttstock from Arms of America and one of our grips.

The lower handguard is what you would find on a kbs wz. 1996A Beryl. The upper is one I had in a box and pretty flimsy. I ordered a genuine Polish upper that I will install after I refinish the rifle.

The upper and lower go on the same as any AKM. I really like the lower – that lip you see makes for a very natural handstop.

Now the buttstock definitely caught my eye. The Poles went through some different models. The first model I see with this collapsing stock is the kbs wz. 1996C Beryl. What I like is that it connects to the receiver the same as any other AK stock so I can change if I ever want to. On the con side, it rattles. I prefer telescoping stocks that are solid. It’s not the end of the world and I’ll live with it to have the unique buttstock.

The grip is our second generation Beryl model. The earlier model Beryls I saw had an AKM-ish looking grip. The first model I have seen with this type of grip is the kbs wz. 1996C Beryl.

Click here if you would like to order one.

The Muzzle Brake

The Beryls were originally chambered in 5.56 NATO and have a unique brake. This rifle is in 7.62×39 so I had to take a departure and go with another brake. Justin McMillion of JMAC Customs makes some very cool effective brakes and ordered his RRD-4C “slim” brake. It looks and functions great.

Note – the Arms of America kit does not come with a cleaning rod so I ordered a Polish AKM rod from them and that is what you see in the photos.

Vortex Crossfire Optic

To round things out, I went with a Vortex Crossfire red dot. I had a few reasons for doing this:

  • Vortex optics are solid
  • The red dot is only 2 MOA whereas some are 4 and can obscure a small target
  • It can sit right down on the rail and be closer to the bore than some red dots

I removed the riser, used some blue medium Loc-Tite on the screws to hold low-rise plate in place and installed it on the rifle.

I used a laser boresighter to sight in the Crossfire plus I lubricated everything and took it to the range with by buddy Niko.

Range Results

The rifle ran superbly. I did find that I need to tune the mag catch a bit to work with steel magazines. It works just fine with the WBP polymer mags you see in the photos and they have a noticeably thinner tab than my steel mags.

A fellow asked me how well the RRD-4C brake works and this video is of Niko shooting at targets – you can see how little the 7.62×39 Golden Tiger ammo is recoiling.

As it stands right this minute, I think this is both my most accurate AK and reliability has been exceptional. So, I still need to parkerize it and finish it but that needs to wait as I have a few other projects I want to line up and do them all at once.

Here’s how the rifle looks right now:

If you find this post useful, please share the link on Facebook, with your friends, etc. Your support is much appreciated and if you have any feedback, please email me at in**@ro*********.com. Please note that for links to other websites, I may be paid via an affiliate program such as Avantlink, Impact, Amazon and eBay.

Poland

Assembling A Beryl-ish AK From A WBP Kit – Part 7 – Installing the Fire Control Group and the Optics Rail

With the 7.62×39 Polish Beryl inspired rifle otherwise complete, it was time to install the fire control group, optics rail and the furniture.  This post will focus on these elements.

The Fire Control Group (FCG)

For some time now I have heard how good the ALG triggers are.  I have grown very accustomed to Tapco G2 triggers over the years and know how to tune them but reports were coming in about their not being in accordance with Russian design specifications so this prompted me to try the ALG AK Trigger with Lightning Bow (AKT-EL).

The trigger comes with a spring booster if you want a heavier pull but I wanted the lighter pull.  Wow – this trigger blew me away.  It installed the same as any other AK trigger.

I would recommend something to them and to you though – make a quick slave pin or capture pin that you can use to assemble the trigger assembly outside of the rifle, lower it in and then press it out of the way when you install the actual pin.  In my opinion, ALG should supply one with their trigger but you can make one from an old trigger pin, an old drill shank, whatever.

6/29/23 – We do make and sell AK trigger slave pins in case you would like to buy one – please click here.

I didn’t even polish the FCG and just inserted it as-is.  Seriously, I will never go back to Tapco.  These ALGs are wickedly good.

I do not like the original shepherd hook wire for securing the FCG pins and instead now use our American made properly dimensioned AK fire control retainer plate.  Click here for the page in our store.

In the next photos you can see the giant over-sized selector lever.  It drives me nuts and will either get ground down or replace by a standard AKM lever.  It’s totally up to you but I will not buy the extended mag release and selector lever again – they just are not my preference.

Our New Second Generation Polish Beryl Grip

At this point I installed one of our new Polish Beryl grips as well. They Beryl uses the typical grip nut that uses a 6mm diameter 1.0mm pitch grip screw.

Click here if you want to order one of our grips.

The Optics Rail

The Beryl was the first AK-platform that I know of that had an integral optics rail that ran from the rear sight block (RSB) to the rear trunnion.  It did not need the traditional AKM side mount optics rail.

Now the WBP kit I bought had a Weaver rail and they have since moved to the Picatinny standard – just FYI.  I believe my rail is known as the POPC III.

I really did not know what to expect when I ordered the kit and was blown away by how the Poles did this.  The rail is solid steel and built like a tank.  It attaches to the RSB via two small grooves that are machined into the back just below the rear sight leaf.

It then locks onto a cylindrical protrusion on the rear trunnion.

This did take some minor fitting.  I sanded off a bit from the front edge of the rail and rounded the cylinder just a tiny bit to help the above pictured hole slide into place.  I went slow and test fit over and over.  This thing locks up incredibly solid – literally zero play.

All that is left now is the furniture and the test firing.

If you find this post useful, please share the link on Facebook, with your friends, etc. Your support is much appreciated and if you have any feedback, please email me at in**@ro*********.com. Please note that for links to other websites, I may be paid via an affiliate program such as Avantlink, Impact, Amazon and eBay.

Poland

Assembling A Beryl-ish AK From A WBP Kit – Part 6 – Reinstalling the Barrel and Pin with IR Air Hammer

At this point we are getting into the home stretch. Once the barrelled kits dried up, virgin barrels required a fair amount of work to install the blocks. Personally, I never really enjoyed doing the blocks so now that completed barrel assemblies are available again, I’ll happily leave that work to someone else.

One quick comment on the WBP kit – I really like the crest on the rear sight block (RSB).  I didn’t expect it and it is so cool.

There are many methods to install a barrel – I have used two – my 20 ton press with an AK-Builder barrel jig and my IR air hammer.  Of the two, I mainly use the air hammer now and that is what I will document in this post.  Note, the AK-builder jig works just fine – I have found the IR 117 air hammer to be faster as I don’t have to do as much set up work.

You don’t have to use the same IR as me but I would recommend you get either a bigger air hammer like mine or at least a 4x air riveter.  An integral regulator in the gun helps with control.

Three Critical Tips Before You Begin

#1 – If you are new to air hammers, practice before you work on your rifle.  They jump around and you need to get a feel for how how control them.

#2 – Mr air hammer is not your friend.  Wear eye protection and do not get skin anywhere near punches, etc.  They can pinch the hell out of your skin.  I’ve had my fair share of blood blisters and cuts from not paying attention or being in a rush over the years.

#3 – DO NOT hammer right on your muzzle.  The crown, or end of the barrel where the bullet exits, is the last thing to touch the bullet.  If you somehow deform the crown you will negatively impact accuracy and you also risk your threads.  Use protection 🙂  I’ll detail that below – I use an old cut down muzzle brake as a protective cap.

Installing the Barrel

To install a barrel, I first install an old slant brake that I ground flat to protect the threads.  I have not used a muzzle nut because they do not seem to offer much protection to the front of the muzzle – they are mainly designed to protect the threads.  With the ground down slant brake, there is a plenty of material in front of the muzzle to protect it.  

You can see how it has mushroomed over time but that’s fine.  I’ve used it a ton and if I ever have a problem, I’ll chuck it and make another.

My best guess is that it came out of a Romanian G kit years ago.  I have a bunch of oddball parts like this that got replaced by US parts for the sake of 922r compliance.  You can use any slant brake you want – just grind the slant off so you have a flat surface to hammer on.

I thread the converted brake / muzzle protector all the way back on the barrel to engage all the threads possible and back it right against the front sight block (FSB).  The idea is that you want the threads to take the impact and not the muzzle.

To start the installation, I push the barrel assembly into the trunnion and tap it with a big ball pein hammer.  I keep sighting down the rear sight block (RSB) making sure it is true.  At the point, you can use a rubber mallet or other non-marring mallet to tap the RSB and angle the barrel slightly one way or the other to course correct.  It is really, really important to get the alignment right at the start.  You will not be able to adjust it once you get very far in.  If it turns out you have alignment problem later, I would recommend driving the barrel assembly out and starting over.

To do the actual driving, I use the IR 117 with the brass peening hammer attachment.  I put the brass hammer face right on the converted slant brake and drive it in.  I keep checking the barrel pin hole to make sure I stop just short of the final location and that it is aligned.  If the surfaces are not aligned, I would drive the barrel back out and start over.  In this next photo, you can see I stopped just short of where I need to be.

Now this particular kit was a headspaced Polish WBP kit and I had checked headspace before I removed the barrel.  If I needed to set the headspace, I would start checking it somewhere around here.

At this point, I drive the barrel in the rest of the way by tapping the end with a big ballpein hammer – or any BFH will do 🙂  It really doesn’t take a ton of energy.  You want to tap and test over and over.  Don’t get impatient and try and drive it in all at once or you risk overshooting where you want to be.  If you do overshoot, it’s going to take some time and you need to make that longer barrel backout tool and either use your press or your air tool (I’d use my IR 117) and push it back out just enough to then fine tune the location.

Do not use headspace gauges as barrel stops.  You may know this but just in case you don’t – gauges are precision instruments and you only install them to test the headspace and *not* as a way to stop travel.  I’ve heard of guys doing that and, for a change, I wasn’t one of them 🙂

Assuming you checked and confirmed the headspace before you began, where to stop is easy.  Once the channel is clear and you have one nice continous path from one side of the trunnion to the other it is time to reinstall the pin.

Installing the barrel pin

With I do is start the pin with a big ball pein hammer and then drive it in the rest of the way with an old rivet set that I use just for this purpose.  Years ago I bought a ton of used 0.401 shank rivet sets and rivet tools off eBay for a very reasonable price.  I use one that covers the pin nicely and drive it right in and let me tell you, it goes in fast.  You can stop short and drive it in the test of the way by hand if you want.  I tend to just drive it right into place with the air tool.

By the way, I’ve accumulated a number of rivet tools and bucking bars over the years.  Here’s a quicksnap shot of my toolbox:

That’s it – done.  I hope this helps you out!  In the next post we will go over the unique Beryl optics rail and installing the furniture.

By the way, here are used rivet tools currently on eBay.  Be sure the shank size matches your air hammer or air riveter (all of mine are 0.401″ for example)

If you find this post useful, please share the link on Facebook, with your friends, etc. Your support is much appreciated and if you have any feedback, please email me at in**@ro*********.com. Please note that for links to other websites, I may be paid via an affiliate program such as Avantlink, Impact, Amazon and eBay.

Poland

Assembling a Beryl-ish AK From a WBP Kit – Part 5 – Riveting In The Trunnions

As I mentioned in an earlier post, riveting the trunnions to the sheet metal receiver is the proven method. As such, I’ll use rivets in this build but there is a fun thing to point out – there are tons and tons of ways to do the rivets. I’ve known guys who:

  • Would fashion some type of bucking bar and hammer the rivets directly not really caring what they looked like
  • Modified hand punches by cutting then down and drilling or milling an inverted dome into the end to create their own rivet sets for use with a hammer
  • Modified the jaws of 24″ Harbor Freight bolt cutters to make rivet squishers
  • Bought pneumatic rivet squishers like they use in the aerospace industry
  • Purchased purpose built rivet tools from makers such as AK-Builder

I got into building rather late in the game in 2006. Fortunately for me, guys had worked out the building methods so I could learn from others. I also decided to buy the AK-Builder rivet jig that I still use today. It works great for setting the front and rear trunnion rivets. I do plan on trying the bolt cutter method some day and will just buy one of the pre-built jaw sets for the front trunnion rivets. I’m curious mainly for reducing the set up time.

Click here to go to the AK-Builder jig page.

Rivet Selection

The AKMs are assembled using soft steel rivets that deform under pressure. No heat is needed. The sizes can vary depending on the type of build you are doing. The easiest way to get the rivets of the right type, size and length is to buy them from AK-Builder.com. They take all the guess work out of it and it makes for an easy way to go plus they give you a discount if you bought their jig. Hint: Buy two packages for a given build. For an AKM, you have 13 rivets and you can readily sort out what goes where:

  • The shortest rivet goes to the rear for the trigger guard strap. This makes sense because you are just riveting two pieces of sheet metal together.
  • You will then notice 10 rivets of the same size but two will be different – they will be what are called “swell neck” rivets and are intended for the rear lower front trunnion rivet positions that are countersunk. Four of the rivets that are flat under the dome will be used for the front trigger guard and four will be used for the foreward two positions on each side of the front trunnion.
  • The last two are the longest and thickest – they go to the rear trunnion.

The following photo shows the two types of rivets you will use on the front trunnion. The top is the swell neck rivet that is used for the rear two countersunk holes on the front trunnon. The bottom one is a normal rivet and is what is used for the four front rivets to secure the selector stop and front trigger guard strap to the receiver as well as for front-most four (two on each side) rivets:

This next photo shows one of the swell neck rivets next to the counter sunk hole it will go in. They require a couple of extra steps to install in terms of crushing the receiver material into the recessed area first before setting the rivet and I’ll explain your options to do that later:

Last comment, you can buy rivets in bulk if you want to. McMaster has some and firms like Hanson Rivet have a huge variety. You basically need to know the dome type and diameter. You get rivets longer than you need and trim them using the formula that the rivet must stick out 1.5 x diameter to form properly. If it is too long you will have problems also. So, you measure the depth you need and then add that to the overall length.

AK-Builder now also sells their rivets in bulk if you are interested – click here.

If you were building from a receiver flat or a tube without a center support, you could consider that as a rivet too but you need to buy that separate as it usually comes with the center support tube it passes through as a set.

This post will be mainly me giving you an overview of what to do and tips based on my experience. AK-Builder has a nice set of instructions you can review by clicking here.

Setting the Front Rivets

In a previous post, I explained how I start with the trigger guard. Next up then is to install the front trunnion rivets.

The AK-Builder rivet jig basically uses an arm to transfer downward force from the press to the rivet to squish it. The domed part of the rivet is held by a small cup and two pieces of thick high density rubber help you stabilize the receiver assembly during the operation. In the next photo you can see the parts plus that I have a 5/32″ drill to help keep everything aligned during squishing.

Now for some tips:

  1. Make sure the arm is as short as you can make it. The longer it is, the more likely it will bend. Note AK-Builder sells replacement arms and I am on #3.
  2. Make sure the little set screw anvil is out far enough to squish the rivet down far enough. These will deform over time and replacements are available from AK-Builder – there are replacement parts for everything from them except for the main body which is built like a tank anyways.
  3. Use the little blue rubber blocks to adequately support the receiver. You want the arm to push down straight. The domed rivet to be sitting squarely in the above cup and to be pushing straight down on the rivet. The little blocks can help support stuff so you can focus on alignment.
  4. When you are positioning the trunnion, make sure the arm isn’t going to press on part of the trunnion.
  5. If you have an air-over hydraulic press, only use the air to run the ram down to the jig. You will not hear a difference before stuff bends. By hand, it is nice and slow and you have time to hear, feel and adjust. I turned an arm into a deformed banana right after I got my air-over-hydraulic jack/bottle. They are a great time saver but know when to switch to the hand pump for the fine work.
  6. It does not take a ton of force to squish a rivet. If your rivet is not squishing make sure the arm is not sitting on part of the trunnion, that the set screw is down far enough and that the bottle’s release valve isn’t partly open.
  7. The last two rivets I do are the countersunk rear lower rivets on the front trunnion. For the countersunk holes that use the swell neck rivet, you can either use the conical stubby press tool from AK-Builder after drilling an 1/8″ starter hole and then 5/32″ as a final step to prepare for the rivet. Important: The little tool is sitting on the base of the jig and you are pushing the receiver down on it. I’m not a fan of this because I can’t see what is going on. Your second option is to do what I do – drill the 5/32″ hole, use a 1/4″ ball bearing and a C-Clamp (on the same side reaching in through the mag well) to push the receiver material into the countersink. This really adds strength and I would recommend you take the time to do this. After you have squished the material in, drill with the 5/32″ bit again to clean up any material blocking the hole.
  8. Last tip – when you are doing the counter sunk holes, do not use the long rear punch – that is just for the rear. The reason for this is that the rear trunnion is solid and you can safely do that. However, with the front trunnion – the counter sunk rivet holes are not connected by solid steel and, instead, the mag well is there. You need to pick a method wherein the trunnion is supported or you risk either bending or breaking the rear “ear” of the trunnion.

Note – you will only see replacement parts for your jig if you bought it direct from AK-Builder and are logged in. I bought mine ages ago and Lonnie had to look up my order and manually turn on the part of the website for me to order parts so just FYI.

The following photo shows me reaching in with the arm and squishing a rivet – the goal height is to squish the rivet body low enough that you can press the barrel back in and it not hit a rivet:

If all goes well, your rivets will look like the following or even better:

I am happy with rivets where the dome is firmly against the receiver. If I mess up, I will drill out the rivet and do it again. Note – The center support rivet was done by Childers and I cleaned that up a bit with my rear rivet set up of the AK-Builder jig.

Setting The Rear Rivets

Next up is to squish the rear rivets. This requires more careful positioning and also support. I have messed up a fair number of rear rivets over the years due to one of those things being wrong. The first thing to do is to remove the arm and install the rear trunnion rivet “bridge”. You will still use the little cup to cradle the rivet head and the rubber strips to help with positioning.

In this next photo you can see the jig set up for the rear rivet. In hindsight, I should not have taken this example photo yet because you first need to use the countersink tool at the bottom to press the receiver material into all four holes and then chase the holes with the drill press to clear any receiver material out of the way before you can install the rivet.

Here is an important tip, after you press the receiver material in, have cleaned up the holes and are getting ready to do a rivet, do some careful alignment and work holding. The piece of metal with a U-shaped cut out goes between the large screw body in the middle and the receiver. Bring that main screw down by hand because you next use the alignment tool – a punch with a hole in the middle to make sure the rivet forming tool (the one with a recessed dome in it) will come down square on the tool. Once it is aligned, use a wrench to bring the main body of the jig firmly down on that metal with the U-shaped slot and make sure nothing moves. Double-check it again with the alignment tool and ensure the rivet head is still squarely in the cup. In my experience you need to use a wrench to bring the body down – it requires more than being hand tight but not so much that you are deforming stuff. The words to think of are “securely aligned”.

Now, use the punch / rivet set with the inverted dome to form the rivet head as you apply pressure from the press. When the tool gets even with the surface of the receiver, stop. If you keep going you will mar the receiver and leave some portion of a telltale dent around the receiver.

Done!

And with that, you should be done and ready to reinstall the barrel.

If you find this post useful, please share the link on Facebook, with your friends, etc. Your support is much appreciated and if you have any feedback, please email me at in**@ro*********.com. Please note that for links to other websites, I may be paid via an affiliate program such as Avantlink, Impact, Amazon and eBay.

Poland

Assembling a Beryl-ish AK From a WBP Kit – Part 4 – Drilling the Front and Rear Trunnion Rivet Holes

In the previous post I removed the front trunnion from the barrel assembly and was then ready to install the front and rear trunnion into the receiver that I had already riveted the trigger guard on. This post will focus on drilling the rivet holes needed for the front and rear trunnions.

Front Trunnion Rivet Hole Drilling

The AK-Builder Trunnion Rivet Hole Drilling Fixture makes locating of holes much easier than the methods I used when I first started. I mainly used the Post-It method where you would rub a Post-It note over the holes and then stick the note on the trunnion as a rough guide as to where to center punch and start drilling. Some guys also make little locator tooks out of spring steel but I never tried one of those.

This jig is awesome. There is one very, very important thing you must do when using this jig – make sure you drill press table, column and the jig itself are secure. If the work can shift while you are sliding the receiver on or off, you are hosed and will drill a hole ut of position. I can’t stress this enough.

The jig is on an X-Y table on my drill press. An X-Y table gives you crank knobs like you have on a milling machine and allows for precise drilling. I use it all the time for drilling grips and other items. Basically you secure your item and then use the X-Y table and a spotting bit or whatever to get you right where you need to be. I wrote a post a while back about the table if you are interested. An X-Y table is not mandatory but boy does it help if you do a ton of drilling.  Note, when you buy the table it will not come with any kind of fixture/clamp set. You will need to buy one that matches the size of the T Slots of the table you get.

If you look at the next photo, you will see a red mandrel sized for AKM-type trunnions. You will slide the trunnion on to that all the way and turn the knob in the back to expand the mandrel and secure everything in place.

So you basically install the trunnion, locate the hole with your press, slide the receiver on and then run the drill down and make a hole in the same place. It’s that easy and that reliable as long as everything is secure. Again, that is the key part here.

I should point out that I prefer to use a center 135 degree cobalt drill bits and cutting oil when I do drill the holes.

Once I have all of the front rivet holes drilled, I move on to the back trunnion.

Rear Trunnion Installation

The rear trunnion is held in place by the other side of the fixture and the tab fits int the part of the rear trunnion where the operating spring guide would normally sit.

Again, make sure everything is secure or your hole locations will be messed up.

With that, it is now time to proceed to riveting in the next post.

If you find this post useful, please share the link on Facebook, with your friends, etc. Your support is much appreciated and if you have any feedback, please email me at in**@ro*********.com. Please note that for links to other websites, I may be paid via an affiliate program such as Avantlink, Impact, Amazon and eBay.