IMR 4475 equivalent

[MrWithasee]

I've been doing some checking and according to most online sources, military M61 7.62 ammo was loaded with 41 gr. or IMR 4475 powder. I have also read that this powder was never made commercially available to the public.

If one were to want to load some M61 stuff, what powder would be the equivalent to the 4475, if any?

[daschnoz]

I've looked too. Good Luck.

The M61 bullet is about 0.100 inch longer than the M80, so my guess is they changed from the WC846 to IMR 4475 to get better powder density in the case without compressing the load, while still keeping the same muzzle velocity.

Looking at the velocity data for the M61 round (2750 fps @ 26 yards), there's no reason you couldn't use any other powder that will meet the velocity requirement, while keeping powder compression in the case to a minimum.

[MrWithasee]

anyone have any intel that shows 3031 as being equivalent to 4475?

[instr8]

I have read that the 3031 data can be substituted. But take that with a grain of salt. I've never used any myself.

http://castboolits.gunloads.com/showthread.php?t=21250

[kycrawler]

i use lots of 4475 and my lot is interchangeable with 3031 data if your close to central indiana i ll trade 4475 for canister 4350 or varget i have about 40 lbs left