Are You Having A Hard Time Finding OEMP164015B FS A2 Rock Island 10mm Pistol Magazines?

Ok, so I wanted to get back into the high capacity 10mm 1911 game. Generically, these are often referred to as 2011 pistols. The first maker I know who used that label was STI back when they offered both 1911 single-stack and 2011 pistols. At some point, the Philippine firearms company Armscor entered the fray with higher capacity Rock Island Armor (RIA) models based on the Para design. Notice how I say “based on” because not everything interchanges. So with a bit of history, let’s skip forward to my 52009 pistol. It’s a nice solidly made pistol and you can usually say that for their pistols. However, I ran into a snag – there are no spare magazines anywhere in the US. I kid you not.

Folks, I seriously scoured the WWW for the magazine the high-cap RIA 10mms use — the FS A2 part # OEMP164015B. Nobody has them – not even the Armscor parts website or Gunbroker.

7/9/2021 Update: We released our third generation magazines for the RIA pistols today and we have plenty of them 🙂 Click here for the listing in our store.

Back when I had my 52000 Rock Ultra, you could get aftermarket ACT magazines that worked great and I bought a bunch. Unfortunately, when I sold my Rock Ultra, I sold the magazines. So, in trying to find mags for my new pistol, I literally visited probably 25-50 vendor web pages that were all out of stock. Argh!

Time to Research

I had the 52009 pistol inbound from Reed Sports – great group by the way, the threat of new gun control regulations and wanting more than one mag all were pushing me to find an alternative source of magazines. I read tons of forum posts, had to sort through a lot of useless data and came away with some important nuggets:

  1. The RIA pistols are based on the Para design so if you own one of the following 10mm models, read on:
    • 51994 TAC Ultra MS 10mm
    • 51914 TAC Ultra FS 10mm
    • 56862 TAC Ultra Threaded 10mm
    • 52000 PRO Match Ultra 6″ HC 10mm
    • 52009 Rock Ultra FS HC 10mm
  2. All RIA high capacity 10mm (and .40 S&W) pistols use the same magazines – the 1911 – FS – A2 series, part number OEMP164015B.
  3. ACT-Mag makes the OEMP164015B magazines for RIA.
  4. Mec-Gar, another magazine manufacturer, sells aftermarket Para P16 Magazines that are for both the .40 & 10mm – MGP164015B
  5. It seems like there were some older P16 magazines from Mec-Gar that had some problems and guys posting in blogs mentioned to look for the newer ones that are made in Italy.
  6. The Para P16 Mec-Gar magazine MGP164015B is not the same as the RIA OEMP164015B made by ACT-Mag — but boy is that numbering similar. It made me wonder about the design relationship – what changed?
  7. There were some very vague comments of guys modifying the P16 magazine to work in their RIA pistol.

My conclusion after a ton of reading: I was betting the P16 design was close to what I needed and hopefully I could make it work with some tinkering. It was time to order in some of the Mec-Gar P16 magazines and see just what the differences were.

The good news – there were a number of website with Mec-Gar MGP164015B Para P16 magazines in stock. I went ahead and ordered in some from Numrich Arms to do my experimenting.

Keep reading – it takes modification to get the mags to work. The P16 mags will not work in a RIA high cap without some changes. You can read to the bottom of this post or jump to the post with the modifications by clicking here.

Small Delays

The pandemic, winter weather and gun regulation fears have all created a bizarre environment to operate in these days. For me and Ronin’s Grips, we’ve been crazy busy for a number of months and that is why you haven’t seen me post much – I haven’t had the time to tinker or write!

In terms of this project, Winter weather in Memphis screwed up all FedEx over night shipments for almost two weeks. Then when the pistol arrived, there was no magazine in the case. I found Armscor to be completely unresponsive for whatever reason whereas Reed Sports got a hold of their new Armscor rep and were able to get me one magazine. Kudos to Reed Sportsthey are a big seller on Gunbroker in addition to their own stores – I would do business with them again and certainly recommend them as well.

Numrich was fast to ship – I had their mags even before the pistol arrived. I did try one out of the box and it absolutely would not feed. The bullet wasn’t remotely pointing at the chamber if would smash into the feed ramp or shoot up at a 45 degree angle and get seriously stuck. I couldn’t do anything until the RIA OEMP164015B magazine arrived.

Do You Really Care About The Finish?

If you are striking out on the blued version of the magazine – MGP164015B – and don’t care about the finish, you do have another option – there is a nickel version that is identical other than the finish and its part number is MGP164015N. Note how all that changes is the last character of the part number from “B” for blue to “N” for nickel.

I don’t know about you but if I needed a spare mag and my choices were no mag or shiny nickel, I’d rather have a spare mag! You could either just live with it or refinish it. Seriously, I’d opt for anything other than just having one mag.

One other option is to get a 10 round version of the magazine. What Mec-Gar did for those was to use a press to press in dimples that prevent the follower from going down all the way. You can drill out those dimples and the magazines will then hold their full capacity.

Safety Comment

I knew I was going to need to do a ton of cycling of rounds. Using live ammo is risky because you have the very real risk of a negligent discharge. To avoid this, order yourself in a bunch of dummy cartridges. There are sellers on eBay that will sell you 10+ at time. Order yourself in 10-20 rounds. You are going to smash the crap out of them due to the heavy recoil spring a 10mm uses. I trashed at least 10-15 of them. Most were due to the bullet being smashed back into the case, one dented the case pretty bad and one deformed the case right at the mouth.

I can’t even guess how many cycles I did – especially starting out. I’m going to hazard a guess and say I averaged about three cycles per dummy before something failed on the dummy as I worked out the kinks and I would load three rounds per magazine to do the testing.

I can’t stress it enough – get dummies to tune your magazines. If you can find them, get the 10mm A-Zoom Snap Caps – they last way longer. The dummies get their bullets smashed back into the case sooner or later.

Next Post – Making the Modifications

In the next post, I’ll go through the details and what you need to do to modify the Para P16 mags to work – yeah, I let that surprise out. They do work but you need to alter them. Click here for the next post.

By the way, if you go to buy the Mec-Gar Para 16 mags, make sure the vendor has them in stock or you are comfortable with how long they say you will need to wait.

After I worked out the process, I converted a bunch of mags for use on the RIA 10mm pistols. Click here to go to the section of our online store that has all of our current 1911/2011 magazines and related products.

7/9/2021: We released our third generation magazines for the RIA pistols today and we have plenty of them 🙂 Click here for the listing in our store.

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.

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