MachIVshooter
Member
So, early last summer, I ordered a 20" 10mm barrel blank from Green Mountain, the intent to build a Stoner gas system AR upper. I picked up an upper and BCG around the same time, and opened up the bolt face and extractor to accept 10mm cases right away. But it took me until now to get around to the barrel. Many other projects, plus $150 for the chamber reamer and barrel extension wrench that I just always seemed to have more important ways to spend. But I finally ordered them last month, and today we tackled the barrel. Threaded the back end, chambered it, installed barrel extension, headspaced, cut muzzle threads (5/8-24) and then profiled it slightly lighter than gov't. profile.
(Sorry for the crappy pic)
It's 10.5" with pistol gas, and I started small on the port for obvious reasons. First shots were stovepipes, so I started opening up the port. Got it ejecting and even stripping new rounds from a 5.56 P-mag, but no lock on empty. So I grabbed the lightened carrier from my featherweight build and took the weights out of the buffer, but still no lock. I decided to call it at 1am, and proceeded to write an email to Ron Williams, the only person I know of making Stoner gas system 10mm ARs. What that means is one of two things:
1) Mr. Williams will have a suggestion for getting it to run right, and I'll proceed with the standard 10mm auto.
2) I will not be able to make this barrel and pistol gas system work with 10mm auto, so I will be forced to do something I've been wanting to do for a long time; build a 10mm magnum
In anticipation of #2 being likely, and the fact that it'll happen eventually anyway, I just placed an order for 1,000 10mm mag cases. So, more than likely, in a short time you all will be seeing video of perhaps the only 10mm magnum AR in existence
10mm mag with bullets loaded long should feed well from a standard 5.56 magazine, and 200 grain JHPs leaving the 10.5" barrel at ~1,600-1,700 FPS is nothing to sneeze at!
(Sorry for the crappy pic)
It's 10.5" with pistol gas, and I started small on the port for obvious reasons. First shots were stovepipes, so I started opening up the port. Got it ejecting and even stripping new rounds from a 5.56 P-mag, but no lock on empty. So I grabbed the lightened carrier from my featherweight build and took the weights out of the buffer, but still no lock. I decided to call it at 1am, and proceeded to write an email to Ron Williams, the only person I know of making Stoner gas system 10mm ARs. What that means is one of two things:
1) Mr. Williams will have a suggestion for getting it to run right, and I'll proceed with the standard 10mm auto.
2) I will not be able to make this barrel and pistol gas system work with 10mm auto, so I will be forced to do something I've been wanting to do for a long time; build a 10mm magnum
In anticipation of #2 being likely, and the fact that it'll happen eventually anyway, I just placed an order for 1,000 10mm mag cases. So, more than likely, in a short time you all will be seeing video of perhaps the only 10mm magnum AR in existence
10mm mag with bullets loaded long should feed well from a standard 5.56 magazine, and 200 grain JHPs leaving the 10.5" barrel at ~1,600-1,700 FPS is nothing to sneeze at!
