22 nosler ar15 questions

[wi50]

I've built several AR 15 uppers where I threaded and chambered the barrel, drilled gas port, etc. But I'm going to build a 22" barreled upper in 22 nosler. I'm using a 1 in 12 twist barrel for 55 gr varmint loads. Going to use an extended gas system. Any idea on how large to drill the gas port? My thinking is to start small down around .070" as the 22 nosler will be at a higher pressure than the .223. I haven't found any specs yet.

 

[rgc54]

That's tough not a lot of info about the sizes I think I would start at .070 like you said for rifle length gas system then go bigger if needed. Or go to bigger and use an adjustable gas block. Normally the longer the gas system the larger the hole. But powder burn rate can change this. Call White Oak Arnament they may know.

 

[RWO]

Nosler's guru says they like rifle length gas system and .078" port. See July AR magazine

RWO

 

[Kurz]

Here is the statement from that article:

There is one last thing that needs attention. With the existing gas port, the gun will likely be overgassed with the increased volume of the 22 Nosler. Mike Lake is the company's senior manager for engineering, research and development, and he is the guy responsible for the 22 Nosler cartridge. He noted that: “Most standard .223 gas ports are around 0.090" in diameter. With the 22 Nosler, we have had good luck using a 0.078" port and a rifle-length gas system.”

If you are using an existing barrel with a larger 0.090" port, the solution is an adjustable gas block. They are available from Brownells (brownells.com) in a wide range of designs and prices. Adjust the gas volume until the bolt locks back reliably on an empty magazine and the brass ejection pattern is at about 2 o’clock.

https://www.americanrifleman.org/articles/2017/6/23/tested-the-22-nosler/

And in a related although obviously larger AR10 system From Proof Research:

Introducing CAMGAS
PROOF Research Announces CAMGAS™ Barrel Design for AR-10® Variants
Caliber Matched Gas System™ offers improved performance and reliability for 6.5mm and .260 (Rem).

With the release of its new patent-pending Caliber Matched Gas System (CAMGAS) barrels, PROOF Research has eliminated the issues traditionally associated with building 6.5mm and .260 rifles on 308AR/AR-10 platforms. Until now, AR-variant shooters looking for ballistic advantages from either of these calibers were faced with excessive bore pressures that necessitated makeshift solutions such as clipping buffer springs, adjusting buffer weights, and/or relying on adjustable gas blocks, to keep their rifles functioning properly.

PROOF’s R&D team has solved the overpressure issue with gas systems tuned specifically to the cartridge/barrel-length combination. “By moving the gas port, the pressure in the bore is given time to reduce to that comparable of a .308 Winchester with a rifle-length gas system, which is what the 308AR/AR-10 system was designed around,” said Greg Hamilton, PROOF’s research-and-development weapons specialist who’s also a 3-Gun and PRS competitive shooter. “The recoil impulse is noticeably smoother, which helps keep you on target while taking advantage of a more efficient projectile. Case extraction is also easier, with less case-head smearing, so the brass is in much better condition for reloading.”

In recent years, 6.5mm Creedmoor and .260 Remington have become increasingly popular in long-range shooting competitions. The .260 in particular represents an outstanding caliber for a military counter-sniper role—out to roughly 1,000 meters—in smaller- to mid-sized weapon systems. It offers exceptional accuracy and superior ballistics over the ubiquitous .308 while dishing out substantially less recoil and enough energy to make it a legitimate contender for military and law enforcement applications.

“I’ve been using prototype CAMGAS barrels, in both .260 and 6.5 Creedmoor, in competition for almost a year with excellent results,” Hamilton explained. “Both rifles ran flawlessly through high-round, fast-cadence stages, firing hundreds of rounds with 100 percent reliability and zero maintenance or cleaning. From recoil to reliability, every aspect of performance was improved compared to the typical un-tuned barrel.”

PROOF Research currently offers Caliber Matched Gas System barrels chambered for 6.5mm Creedmoor and .260 Remington in three separate lengths: 20, 22, and 24 inches. Every CAMGAS barrel comes standard with an easy to install custom-length gas tube.

https://www.proofresearch.com/the-company/introducing-camgas/