7331 Powder?

[raven290]

I had a customer come into my store today and he was telling me about a weird powder. It's called 7331 and it came in an 8lb jug. He bought it at a gun show in Idaho. He says its supposed to be a .50 cal flashless spotting rifle powder. He says it spikes pressure quickly and can "overflash" if you under load it. I've never heard this term, but I'm fairly new to reloading. He says that it means it will burn all the powder at once instead of steadily. He doesn't know anything else about it. Has anyone ever heard of this stuff? Or have any load data?



Hopefully I turned him into a calgunner by referring him to check this thread out.

[FLIGHT762]

I had a customer come into my store today and he was telling me about a weird powder. It's called 7331 and it came in an 8lb jug. He bought it at a gun show in Idaho. He says its supposed to be a .50 cal flashless spotting rifle powder. He says it spikes pressure quickly and can "overflash" if you under load it. I've never heard this term, but I'm fairly new to reloading. He says that it means it will burn all the powder at once instead of steadily. He doesn't know anything else about it. Has anyone ever heard of this stuff? Or have any load data?



Hopefully I turned him into a calgunner by referring him to check this thread out.

It's IMR 7383. Lots of information about it on the net. You have to know what you're doing with this stuff. It's a triple based powder and is very finicky. Not for the new reloader. There's a reason this stuff is available when all other more suitable powders have been all bought up in this last panic.

I do use surplus powders, WC844, WC846 and WC852. They work very well.

Personally, I won't mess with IMR 7383.

[Fjold]

Undercharging with slow powders has been known to cause detonation for a long time. I've never heard it called "overflash" though.

[raven290]

Thanks for the answers. I hope he ends up seeing this thread, I wasn't expecting answers so quickly.