300 AAC Blackout

[wlc]

Just got to really shoot mine a good amount today. Loaded with J bullets. It shot pretty good at 50. Haven't measured yet, but less than an inch at 50 if I throw out the called fliers. Loaded with 1680 and either 208gr AMAX or 225gr BTHP. Got to drop my load just a tad as most were just supersonic in my rifle with a can on it. I had three I had loaded with 190gr Hornady spritzers over a charge of RL7 just to test for function etc. Those sounded like a pellet rifle and cycled my carbine gassed action with bolt lock back on the last shot. I like the round and really like the quiet of having a can on the end. I really am of the opinion that every firearm sold should come with one as standard equipment.

ETA: Factory Rem subs don't shoot worth a darn in my rifle. Not accurate at all and often have a fail to feed and not lock back the bolt.

[usmcscout]

467

http://www.castpics.net/subsite/TopPunches/Lee.html



2400 is a great powder and does well in a bolt gun but as you discovered it is too fast to provide enough gas volume for reliable functioning.

well thats my prob I have been fighting find good load stoped at like 18 gr or so with 147 gr mil surp pulls and an old ideal mold 180gr acurite as hell in my rem 700 .308

so now I can give up on 2400 I was thinking I was doing something wrong thanks jailer

[Moonie]

I've had great luck with the Lee 312-155 over 15.3gr of W296/H110 (about 1,850fps) and 245/247gr NOE/Accurate mold over 12gr RL-7 (about 1,200fps, if memory serves me correctly)

[DanWalker]

Has anyone tried H335?

[felix]

On the agenda. ... felix

[saz]

The success of certain powders is directly linked to the burn rate in relation to the length of the gas tube correct? If so, where is that happy place with faster powders? 2400, 1680, Lil Gun etc? Faster powder, shorter tube? I am sure it relates to supers vs subs also.......

[Jailer]

As Felix has mentioned before, if you know you are going to be using faster powders and boolits go with a pistol length gas system and an adjustable gas block. It will give you maximum flexibility in powder choices. Lilgun is about as fast as you can go and still get reliable functioning with supersonic loads in a carbine length gas system.

[MGySgt]

AA1680 and H110 work well in a Carbine length gas system.

[DanWalker]

I would think you would need a larger gas port to see any effect from an adjustable gas block. A regular gas block allows full flow from the port anyhow right?

[Jailer]

I would think you would need a larger gas port to see any effect from an adjustable gas block. A regular gas block allows full flow from the port anyhow right?

In a carbine length system yes you would. In a pistol length system the gas port is located closer to the chamber producing a longer pressure pulse from increased dwell time. With supersonic loads you can easily over gas the system. If you add an adjustable gas block to a pistol system you can limit the amount of gas for supersonic loads with slower powders and open it up for faster powders like the OP was trying to do.