Guess I'm out of the loop. What is it derived from and how is it formed? What is the intended platform and use? Packy.

Are you referring to the 300ACC Blackout? If so, it is derived from necking up 5.56 Nato case up to .308. According to what I have read this cartridge is designed to operate in the M4 platform at subsonic velocities for covert military use. If this isn't the cartridge you are referring to then I don't have a clue.

I see you are right. I read about the case but it was mis-named. What do you know about the 300 ACC? Is it straightened out or is there a miniscule neck to hold the bullet? I have a 7mm TCU as a similar 5.56 based case.

quote:

Originally posted by packrattusnongratus:
I see you are right. I read about the case but it was mis-named. What do you know about the 300 ACC? Is it straightened out or is there a miniscule neck to hold the bullet? I have a 7mm TCU as a similar 5.56 based case.

There is a tiny shoulder.

I help a friend prep brass for his and we basically start off my sawing a .223 case off at the shoulder and forming it. The cases come out plenty wrinkly but it straightens out on fireforming.

Commerical brass gives thinner necks than military to the end product so you can can experiment with what works best in your chamber.

At the moment we are playing with subsonic cast lead bullet loads using Vit N310, we have manged to get them down to 1.5-2" at 100 so far and will keep experimenting.

The rifle is a straight pull AR15 platform with a suppressor. the action is the loudest thing about the rifle with subsonic loads.

Is there not a very similar cartridge calle the .30 Apache? Was in an old Frank Barnes book.

Thanks Ghubert, for sharing.

Packrattus,

The original design is the 300 Whisper, just necking the 221 Fireball up with no changes. That leaves a thin neck, prone to splitting after a few reloads. If you run a FL 223 case thru the sizer die and trim you get the same case, but with thicker necks. AAC had envisioned it as a subsonic home wrecker for LEO/Military applications. Mine is built on a pistol stamped LAR receiver and a 10.5" bbl. With a YHM Cobra 9mm suppressor you can hear the recoil spring bottom out and the buffer go "Boing!" when the action cycles.

For a good look, type in 300BLK on youtube.

Supersonic loads, figure a 125-130gr jacketed bullet about 2200fps. Remington bought the company, and already has ARs out.

The really neat part of the deal; you can use the standard AR 30 round magazine and fit thirty in.

Check www.Bradswarehouse.com out. He is a disabled Iraqi veteran and offers processed brass ready to go for about nine cents (using your brass) a case out of Provo, UT.

Rich