300 blk boolits

[dunkel]

Anyone shooting some sort of cast 300 blk? I'm thinking mostly sub-sonics, as I don't think I want to push cast at full speed through this thing.

[prsman23]

Tons of people are. Do a search and you will find many helpful threads and even some group buys for molds.
Midway has a lee mold specifically for blackout and the lee 155 and 160 312 molds have been used very successfully.

[Jupiter7]

I run only 150gr and up cast in my (3) 300blk guns. About 2k fps is max you can get in a 16" barrel with 150ish grain boolits. No ill effects from running thousands of cast boolits in 3 different AR's. Sub-sonic plain based heavies actually required more attention. .310 with proper lube and alloy solved all issues. Subs are more like magnum pistol rounds.

I use the accurate molds 310-240e, drops at 245grs with air cooled range scrap. Actually run it as a mild super(1250fps) unsupressed you can hear it smack a cardboard target backer with earplugs in.

[Frozone]

Anyone shooting some sort of cast 300 blk? I'm thinking mostly sub-sonics, as I don't think I want to push cast at full speed through this thing.

Been working with the MP311410gc and 2400 in a pistol length system.
Max seems to be 13.3gr.
Haven't found the bottom yet, I need to try from 9gr and up to 10, but 11gr gives Very good accuracy at @ 1500fps

[dunkel]

I do have some 2400 that I've been using for lead .357 loads...hadn't considered it for 300 blackout.

I'll do some more digging around here. It's at least good to know that people are doing it with no problems. My buddies that got into 300blk before I did are all running 16" barrels and more or less full powered FMJ loads...so their experience is not helping me with my 10.5" and subsonic aspirations. They're concerned about the lead in the gas system, but I guess that's not a problem.