There we were on the last day of SHOT Show 2017, feet burning and dead tired when fellow writer Travis Pike and I were waved over to the Windham Weaponry booth by our Editor in Chief former Army Green Beret Mark Miller. One thing we figured out early when working with Mark is that if he tells you to stop and check something out, chances are it’s not going to be ordinary. What waited for us upon our arrival was the Windham Weaponry RMCS Rifle System. To me it felt like I was staring at the loch ness monster of the gun world, something people said existed but no one was ever sure was going to be proven.

Enter the RMCS 

In a perfect world of gun fantasy most of us would love to be able to use one gun and switch back and forth between AK-47 and AR-15 magazines and have a quick change barrel system. It would be even better if we had some sort of standardization of parts and be able still get some aftermarket trigger kits or something along those lines. Well that is exactly the sort of hopes and dreams the engineers at Windham Weaponry tapped into and that is exactly what they did with the RMCS Rifle system. We quickly peppered the Windham staff with question after question in fast succession and we we found out about the RMCS was the following

  • Built by Windham Weaponry of Windham, Maine
  • Uses standard AR-15 trigger group so you can get aftermarket triggers if you want
  • Magazine well separates from the rest of the lower receiver
  • Comes in 2 , 3, or 4 caliber kits
  • Available calibers include 9mm, .223, 7.62×39 and .300 AAC Blackout
  • Uses low profile gas block
  • Features quick change barrel system
  • Barrels are 4150 Chrome Moly Vandium Steel
  • Lowers are 7075 T6 Alumnium
  • Lifetime warranty
  • 9mm variant uses Colt sub machine gun magazines
  • Uses stock AR15 buffer tube and M4 style stock

There may have been other companies who tried similar projects but I am unaware of them actually coming into the commercial market. When we spoke to the staff at the Windham booth they said they had over three years of research and development into the project. Apparently the company purchased the project that was incomplete from a company in their local area and invested more time and capital into it to arrive at the finished product that was before us.

In the above video if you skip ahead to the 1 minute mark you get an idea on how the quick change barrel system works. At roughly the 3 minute mark the video shows exactly how easy it is to change out the magazine wells. The video also goes on to warn the user about dry firing the gun, in order to make the magazine wells removable the company had to narrow the space between the hammer and the back of the magazine well. I don’t think this is a huge concern but just something that Windham had to inform users about.

The RMCS is not cheap but it does offer a user a significant amount of expandability in the system. The RMCS -2 is the base model and comes with two caliber conversions one barrel in .223/5.56 NATO and one in .300 AAC Blackout. A second kit the RMCS-3 includes both the .223/5/56NATO, the .300 AAC Blackout and one magazine well and barrel chambered in 7.62×39. The top of the line kit is the RMCS-4 and it contains all of the previously included barrels and magazine wells in addition to a 9x19mm barrel, bolt and magazine well for Colt pattern sub machine gun magazines. Each kit ships in a locking airline approved hard case with custom cut foam inserts.

MSRP Prices: