With the new lower completed I was ready to find a new complete upper receiver for my Precision Rifle project. I had been trying to buy a Bushmaster Predator upper for some time. I liked the concept of a longer, heavier barrel, simple aluminum handguard with no rails and a low-profile gas block, all good things for a scope-only rifle. The trouble was they were very difficult to find at a reasonable price right at the time I was building the rifle (August 2012). In fact they were only in stock at a few places selling them for 200-300 more than the normal sources.
Bushmaster had for many years been building a 24″ barreled AR-15 rifle and separate upper receiver that they referred to as a “varmint” gun. This design used a heavy, long barrel for use on Prairie Dogs and other small pest species often shot at great distances out on the plains. They introduced a variation on this theme that they now call the Predator, which is very similar to the varmint gun but with a 20″ barrel. This was intended to allow the gun to be more easily moved in the woods and to cut down on the weight slightly. This would allow using the gun for a stalking hunt without needing a sherpa to haul it. Although the design wasn’t perfect for my Precision Rifle Project, it was pretty close.
Alas, as much as I liked the Predator, they just weren’t available for anything like a reasonable price. Then I got an email from Aim Surplus that contained an ad for an upper from R Guns that seemed very close to the Bushy Predator specs.
The upper receiver in the ad was the R Guns 20″ Stainless Steel Super Bull Barrel model. At just over $400 this was exactly what I wanted at a price I could hardly believe. I ordered it right away and got it a few days later. Uppers are not firearms so it came right to my door.
When I received the upper I was amazed at the quality of the assembly. The “Super Bull Stainless Barrel” is striking. It jumps out at you on first viewing. It’s nearly an inch in diameter throughout the entire length of this National Match barrel. At 20″ it allows a heavy bullet to accelerate to nearly 3000fps before leaving the muzzle. With it’s 1-in-8″ twist rate the barrel is perfect for 75gr .223 bullets but can still handle 55gr FMJs without too much rotational force. Add to it the aluminum free-float handguard and the low-profile gas block and you’ve got a very nice assembly for a precision build. The upper went on the assembled PSA/DPMS lower perfectly. The Bolt Carrier Group (BCG) functioned flawlessly as did the Fire Control Group (FCG) through dry fire and manual function check.
Without a forward rail I couldn’t throw on some iron sights and go shoot so now I had to decide on a scope. Sure, I could have put a small scope on the gun and given it a whirl but I wanted to wait until I got something more appropriate for this rifle’s capabilities. In Part III we will cover the Simmons Whitetail Classic which has turned out to be ideal for the project.