3rd Gen Custom RIA FS A2 2011 10mm 16 Round High Cap Magazine
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This is our third generation of magazine for the Armscor Rock Island Armory (RIA) High Capacity 2011-style 10mm and .40 S&W pistols that use the 16 round FS A2 magazines – they are not for the traditional 8-round 1911 pistols (I would recommend Wilsons or Tripp Cobras if you have one of those and lots of websites carry one or the other).

These are converted Mec-Gar Para P14-45 magazines that have the feedlips adjusted and fine tuned to properly retain and feed 10mm rounds.  Note, a normal P14 mag can’t securely retain a 10mm round because a .45 ACP case diameter is 0.4734" while 10mm measures 10.8mm (0.425") and .40 S&W measures 10.77mm (0.424").  What you tend to find is that a 10mm cartridge, which is what I shoot, can sit in a .45 ACP mag but it will pull out or even fall out of the magazine far too easily.  The feed lips must be adjusted to properly retain the 10mm & .40 S&W cartridges, which is exactly what we do.

These hand-tuned mags will only work with 10mm and .40 S&W.  They will no longer feed .45 ACP correctly - just 10mm and .40.  Mec-Gar stamps "P14-.45" on them and I do not have a way to change that.  

I am getting a couple of emails each day asking if I really have these magazines -- Yes, I really have these on-hand if the inventory says I have a certain number in inventory then that is what I have.  A lot of guys tell me they have been waiting months to get mags from other vendors or have been scammed.  That is not the case with us - I actually have these mags because I am making them.

These custom mags should work with Armscor RIA pistols that use the OEMP164015B FS A2 double stack magazine.  The RIA pistols that use these mags iinclude:

  • 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
  • 51738 Pro Match Ultra H - 40S&W - note, I tune for 10mm as I don't have a .40 so some minor adjustments might be needed.

The adjustment process and tooling took some work because Mec-Gar uses surprisingly resilient hardened steel magazine bodies and feed lips.  I had to develop a specialized jig and process to bend the feedlips to properly retain and feed 10mm rounds to the ramped supported barrel that RIA uses in the above pistols.

So, in case you are wondering why convert the P14-45 Mec-Gar magazine design?  There are some really cool benefits from the high quality Mec-Gar design:

  • Mec-Gar's quality is superb
  • Hardened steel bodies and feed lips will hold up very well with extreme use
  • Mec-Gar developed an anti-friction coating that aids in feeding
  • The magazine spring is made from type “D” music wire and holds up nicely - I think it is far better than the original Para springs.
  • They developed a polymer base plate that fits very nicely in the large RIA mag well funnels
  • The slightly taller magazine body clears the RIA mag-well funnel very easily.  It’s longer than our previous generations of magazines and is even slightly longer than the original RIA/Act-Mag magazine
  • The magazine’s specified capacity is 16 rounds of 10mm.  It’s a tight fit but I can often fit 17 rounds in there but I can’t guarantee it.

One small detail, since these were originally for .45 rounds, the mag round indicator counts doesn’t match since you will be loading either 10mm or .40 – usually you have one or two more rounds of 10mm/.40 compared to what the round count hole label says.

A fellow asked if I had made many magazines for the RIA pistols and I told him I have sold well over 500 at this point.  


After the mag lips are tuned, each magazine is tested in either my 10mm RIA 52009 or my 10mm 56282 pistols to ensure proper fit and feeding.  You may find some final tuning is needed on your particular pistol and it is easy to do – please click here for more information.  Buyers that are using these in 10mm pistols tell me they run without any changes needed.  Nobody with a .40 has reported back ... or told me they were buying a mag for a .40 for that matter.

Please test the magazines before you need to rely on them. My liability is limited to the purchase price of the magazine and they are warranted against defects (not including any required feed lip tuning) for 90 days. 

Dawson Plates and Wolff Springs

We do sell Dawson base plates if you wish to have one that extends further than the included Mec-Gar plate (the Mec-Gar plate fits fairly flush and is easy to insert and extract).  The +100 Dawson plate sticks out just about as far as the polymer plate so a +200 or +300 plate would actually make the magazine taller - note that the plates add height only but not capacity.  Please click here if you are interested in Dawson plates.

The Mec-Gar spring seems pretty robust and that is what I am personally running.  If you want an even stiffer spring, we do sell Wolff magazine springs that are 10% stronger than the originals. It does require a bit of shaping to fit the follower.   Please click here if you are interested.


Due to irrational firearm hysteria, I will not ship magazines to locations listed in the USCCA magazine limit guide page that prohibit magazines of this size (16 rounds is my stated capacity) plus try to maintain a list of other areas. I will not ship disassembled "magazine kits" to those locations either - sorry. I can't export them either - I hate having to put all this legal stuff in but I must.  It is the buyer's responsibility to ensure compliance with all applicable laws and regulations before buying these magazines.

We can't ship these magazines to the following states:

  • California: 10 round limit
  • Colorado: 15 rounds
  • Connecticut: 10 rounds
  • Hawaii: 10 rounds
  • Illinois: 10 rounds
  • Maryland: 10 rounds
  • Massachusetts: 10 rounds
  • New Jersey: 15 rounds
  • New York: 10 rounds
  • Washington D.C.: 10 rounds


This is for one magazine - the pistol in the photos is not included.

Please do not use Paypal to purchase magazines.  We do take American Express, Master Card, and Visa so please use one of those methods.  Sorry - Paypal's policies do not allow for many firearms and parts transactions but we have quite a few pro-gun customers who do like to use them for other products we sell.

Customer feedback from emails:

9/10/21 "I thought for sure you were a scam and only bought one mag.  I was surprised when it showed up and worked great.  I just ordered three more." - Thomas

8/18/21 "Your 40/10mm magazine works perfectly on my Rock Island A2. Yours was the only magazine I could find for that firearm now and I am 100% happy that it fit and function just fine." – Kurt

8/18/21 "I purchased 2 mags and can say they are a good fit and work as well as the 1 factory original that came with my RIA 10mm 1911. I haven't been to the range yet but when working the slide they were flawless in loading and extracting both round nose and Hollow points. I will be ordering more." - Branko

"Thank you so much - I only got one mag with my FS HC and really wanted two.  Your mag works great!" -- Tom, Arlington, TX.

"I always want four mags for my pistols and could not find that RIA mag anywhere.  Your's is just as reliable as the one that came with my pistol." -- Steve, Madison, WI

"Wow - I thought you guys might be a rip off.  I got the mags and they run great.  I'll be back for more." -- asked that I not post his name.

"I was nervous when I got my mags and they said 14-.45 on them but they hold and feed my 10mm rounds really well.  I have no idea how you got those lips to bend so evenly."  -- Mark in Montana

"I took my four new mags to the range and they functioned flawlessly in my FS HC.  Thank you!"  -- D.S.

"Just got back from the range and the two mags worked great.  No problems with feeding or dropping freely from the pistol.  Thank you!" -- David W.

  • Item #: RIA10mmHiCap16Rnd3rdGen

3rd Gen Custom RIA FS A2 2011 10mm 16 Round High Cap Magazine

Price: $44.99
Sale Price: $39.99
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