I was able to get out and shoot my 16" 12.7x42mm / .50 Beowulf that I finished up a couple weeks ago. I fired 40 rounds with 2 failures to feed on the first round out of the mag. No failures at all during normal firing. Ejection was at about 4 o'clock consistently @ around 3-4 feet. I was shooting Underwood 350 gr. FMJ. It shoots those into 2-3" @ 50 yards, usually with 2 touching and one flyer, which seemed to consistently be the first round fired out of the mag. Recoil is about what you would expect and I likened it to a high brass 12 gauge field load. Hopefully when I get some hunting rounds it will shoot a little tighter group, but honestly, for the intended purpose of this gun, the accuracy is fine. I will probably sight this in @ 75 yards for hunting with hunting loads. I only fired 40 rounds and at $1.57/ round, it was getting expensive real quick.
It is a BCA upper receiver assembly that I swapped out the handguard on, Primary Arms Classic Series 1-6 scope on an Aero Precision Ultralight mount, Anderson lower & trigger, FDE cerakote controls, Magpul MBUS 3 sights, Magpul stock and grip. I upgraded the bolt with Wilson Combat extractor & ejector springs and one piece gas ring. I also installed a .308 Carbine buffer spring & H1 buffer. I have an H2 & H3 buffer to try in it as well, but it functions great now. The recoil impulse is pretty sharp, so I thought I would experiment with the heavier buffer. Most parts were acquired either locally or from AR15Discounts.com with the upper bought on sale @ BCA. I have 3 uppers and a few other barrels from BCA and have had no issues with any of them. With the sales they run on their upper assemblies, they are hard to beat for the price. Normally I piece together uppers, but in an odd caliber such as this, I tend to stick with factory assembled for the first one to learn the ins and outs of it. I may build a 12.7x42 pistol later down the road after all the ATF crap is sorted out.
Overall, I am happy with the build and feel it will be a great brush gun for the thick areas where I deer hunt. It is fun to shoot, albeit expensive, but I have always wanted to build up a big bore AR, and this is as big as it gets without moving into an AR10 sized rifle.
It is a BCA upper receiver assembly that I swapped out the handguard on, Primary Arms Classic Series 1-6 scope on an Aero Precision Ultralight mount, Anderson lower & trigger, FDE cerakote controls, Magpul MBUS 3 sights, Magpul stock and grip. I upgraded the bolt with Wilson Combat extractor & ejector springs and one piece gas ring. I also installed a .308 Carbine buffer spring & H1 buffer. I have an H2 & H3 buffer to try in it as well, but it functions great now. The recoil impulse is pretty sharp, so I thought I would experiment with the heavier buffer. Most parts were acquired either locally or from AR15Discounts.com with the upper bought on sale @ BCA. I have 3 uppers and a few other barrels from BCA and have had no issues with any of them. With the sales they run on their upper assemblies, they are hard to beat for the price. Normally I piece together uppers, but in an odd caliber such as this, I tend to stick with factory assembled for the first one to learn the ins and outs of it. I may build a 12.7x42 pistol later down the road after all the ATF crap is sorted out.
Overall, I am happy with the build and feel it will be a great brush gun for the thick areas where I deer hunt. It is fun to shoot, albeit expensive, but I have always wanted to build up a big bore AR, and this is as big as it gets without moving into an AR10 sized rifle.
