Barrels

When I started into the AR10 project it became obvious that the heart of the performance formula was in the barrels. The problem is that no one, to my knowledge, produces an off-the-shelf barrel selection for the AR10.

The AR10/SR25 units are NOT simply a larger .223. There is not a sea of defense contractor suppliers out there that have a base line production with vast amounts of units and spares over the last thirty odd years like you will find for the .223. Prices and availability reflect this.

No one carries a stock of AR10 barrels for several reasons.
First, they have to be supplied to the customer short chambered. This means the customer has to have the knowledge to finish ream the chamber.
Second, the twist rates add another variable.
And third, the gas systems are totally dependent on final configuration - a 16" carbine designed for heavy bullets vs. a 20" configured for "grind up" ball ammo are separate entities.

Contouring a barrel is a technical problem because it creates other sets of problems as the work proceeds. Every time a cutting tool contacts metal the grain structure is changed. In the case of the Stoner/AR design, there is a great deal of molecular disturbances by the time we arrive at the finished shape. Add fluting then you have a piece of metal that is about as far from 'normal' as a Jackson Pollack painting. For example, a 17-4 Blackstar barrel in a 16" rifle that produces 1/2 moa out to 800 yards was cryo'd some 5 or 6 times (we lost count) after the fluting operation before the harmonic frequency was flat. Cryoing was done before and after initial contouring.

Another issue is chamber dimension control. My reamers are specific to the round the unit is destined to launch. Reamer design is a key to match performance in a semi-auto function. Match accuracy combined with perfect cycling is a tough act to accomplish. For example, SAAMI spec has .343 as a neck dimension yet my reamers are .340 with ogive dimension specific to the bullet. Remember that the luxury of long loading the round is not present. The magazine governs overall length.

AR15 series barrels are a lot more plentiful and selection is quite varied. Until the AR10 developes more active supplier side we are stuck with its uniqueness.

To chamber a barrel minimally, I need the bolt and preferably, the entire upper receiver/bolt assembly.

Contact Stewart Wilson to discuss your individual requirements.
swilson@shooterready.com