AR 5.56 to Ackley

[Bill K]

Anyone play with a 223/5.56 opened to a Ackley version ? Am thinking the brass would last longer and overall action smoothness would occur. What are some opinions ? Bill K

[Rick in Oregon]

Bill, I've heard from various sources that the Ackley Improved version in an autoloader causes jamming issues due to the very minimum case body taper of the improved case. The original 5.56 was designed with body taper in mind to be used in FA weapon systems that ensured reliable chambering and extraction during sustained fire. It would be easy to tear off a case rim with the M-16 extractor and leave the weapon useless without adequate case body taper to ease extraction from a hot chamber.

In a varminting scenario, it may not have such ill effects if slow fire was the norm to keep the chamber cool and clean. But I'm a fan of the 223AI in bolt guns for PD's and chucks; been shooting mine since '96.

Ask this over on the AR forums.....I'm sure someone is shooting one and will extoll it's virtues.

[Bill K]

Rick. The fact that the case is much hotter in the AR chamber, as it comes out, is along the lines of what I was wondering about, and it maybe sticking. Also the lack of taper feeding.. To save problems and such, believe I will leave the AR's in 223/5.56 and stick to the AI's in my bolts. Just a wild thought/hair Bill K

[PLATAPUS]

I have one. Lee from Insight Shooting Systems built the barrel for me and I put it together. Alot of the negative you hear on the .223 AI in an autoloader is a fallacy. Lee is the grandfather/pioneer of the the AI in an AR. He maybe retired now but I'm sure he will answer any questions and may be able to direct you to someone to build.

Lee favored the 40 grn pills out of a 26" 1-12" @ 4000+ fps where I had him build me a 24" 1-9" for the 69 mid weights.