New from California

[Kodiak]

Love the idea of the 6.5 Grendel. I put one together and have been trying to work the kinks out. I used a Ballistic advantage barrel at 20 inches, and even using Hornady black 123 grains I'm no better than 2 inches at 100 yards. So, back to the drawing board. New upper on the way and think I will put a 22 in Criterion barrel with headspaced bolt on it. Any input would be great... Thanks

[just_john]

Welcome to the clan, KK, from the great nation of Texas. The barrel is ( should be ) capable of much better than that. The key is the interface between the barrel and the upper receiver. If it is a forged receiver ( preferred ! ) then be sure that the mouth of the receiver extension is square to the bore. There are a number of companies that make a tool to do that with. Then, when you mount the barrel, use some kind of holding device with the barrel standing vertically with a reasonable amount of "glue" around the barrel extension. With the various Loctites, the viscosity is such that it will usually wick full perimeter and help make the barrel mount more concentric. When I do this, I just snug the barrel nut overnight while the "glue" sets up and then snug it down the next morning.
If this process isn't followed, the barrel can move within the receiver extension "jsut a little" but that's all it takes to mess things up. I've stated before on these pages that a well assembled upper with average parts can outshoot some top dollar uppers that are just thrown together.
There was an excellent article by Peyton Sweeney in one of the Guns & Ammo mags a year or so ago where he took an average shooter and did as described above and made an outstanding shooter out of it. He stated that he was amazed at the difference that it made.

[FLshooter]

Welcome from Florida’s Spacecoast

[Kodiak]

Great info. I will get that Brownells tool, Lap the upper receiver. Thanks

[A5BLASTER]

Welcome to the horde sir.

[VASCAR2]

Welcome to the forum Kodiak! Make sure the gas block is not hitting the hand guard under recoil. Like others mentioned I’d make sure the receiver is lapped and a snug fit between the barrel and upper receiver. I use blue Loktite on my barrel extension when mating to the upper receiver.

[Kodiak]

Hey thanks, I'll check the gas tube, handguard clearance. There are so many variables to consider when accurizing a gas gun.