Ok, let’s take the heresy a step further. In a previous post I described taking a milled stub and welding it to a sheet metal receiver. Another approach is to drill, tape and use alloy screws. So, let’s talk about that a bit. I did this build back in 2010 also. I actually still have the rifle and it’s one of my most reliable AKs. It takes about any ammo I stuff in it and I don’t recall ever having any issues.
For those of you who are wondering why I didn’t do rivets – I was bored and wanted to try something different plus this is a range gun and not something mission critical. Here we are 7 years later and it’s still doing fine – no cracks, no loose screws … but it isn’t stressed either. When in doubt, do rivets or a milled gun.
In terms of this build, I milled the trunnion down the same as I did for the weld build. I used my Hungarian AMD trunnion as an approximate guide for locating the holes and used two #10 screws for the front top and a 1/4″ for the rear. In both cases, I opted for national fine. 10-32 and 1/4-28. So, for 10-32, I used a #21 drill bit to make the hole and for the 1/4-28, I used a #3.
For drill locating and drilling the receiver holes, I used the AK-Builder trunnion rivet locating jig. You just put the trunnion on the jig, locate the hole, slide the receiver on and drill the hole.
Now for tapping, being square is a good idea. I squared my table to the drill press’s chuck and used it to hold the tap. I use Tap Magic cutting fluid to lubricate everything.
For the screws, I used alloy button heads and secured them with red thread locker. I reached in with a Dremel and ground down protruding screws.
So there’s the front. I used an air riveter to do the trigger guard.
I’ll post some more on this build in future posts.
So, here are some links for you:
#3 drill – these are expensive on Amazon. Before you buy any drills or taps from Amazon, check out McMaster, MSC and other industrial sources first. I used to get a lot from Enco but they were acquired by MSC so I pretty much look at MSC and McMaster for cutting tools plus a few specialty items from other places.