IMR 7383 Surplus
Posted: Sun Aug 07, 2022 5:41 am
I am posting this as an FYI since powder is so expensive. There is lots of information about it on the web. Some have excellent luck with it. Until you find the sweet spot unburned powder can be a problem. It's not a powder you can just throw in a case and go to the range. Start with low charges and work your way up until it is burring clean with no signs of excessive pressure.
So far, I have used it in my M1 Garand, custom 7X57 Mauser and the M91 with good results.
http://www.surpluspowder.com/gunpowder.html
He only has lot #48,000 now that I have not experimented with so my loads will have to be reworked with it. Different lots can and will have different burn rates!!
My experiences:
M91 Mosin Nagant rebarreled and new stock added in Finland in 1942. Has an 1895 dated action manufactured at the Chatellerault arsenal. It's beat up and a little ugly but shoots very well.
Cleaned the barrel between each load. Shot 5 rounds of each load.
Hornady 150 grain .312 bullets. Rifles bore was slugged and came out to .311.
Started at 48 grains of IMR7383 Lot 40,000 and stopped at 49 grains. At 48 and 48.5 grains I had two or three granules of unburned powder. At 48.8 and 49 grains no unburned powder. A little sootier than my commercial powders but not too bad. Very little smoke as well and no ammonia smell. I'm sure the longer barrel on the M91 helps to burn the powder better.
49 grains were the most accurate load with a spread of 2 3/8 inches at 50 yards. Taking out the flyer the spread was 1 5/16. I don't have a chronograph, so I proceed very slowly and check every piece of spent brass for excessive pressure after every shot.
Pic here. Next time out I'll go out to 100 yards.
Please use extreme caution working up loads with IMR7383!! If you are a novice stay with commercial powders. In any event don't take any loads you find on the web including mine and not start low and work your way up.
Your results may vary.
Bill
So far, I have used it in my M1 Garand, custom 7X57 Mauser and the M91 with good results.
http://www.surpluspowder.com/gunpowder.html
He only has lot #48,000 now that I have not experimented with so my loads will have to be reworked with it. Different lots can and will have different burn rates!!
My experiences:
M91 Mosin Nagant rebarreled and new stock added in Finland in 1942. Has an 1895 dated action manufactured at the Chatellerault arsenal. It's beat up and a little ugly but shoots very well.
Cleaned the barrel between each load. Shot 5 rounds of each load.
Hornady 150 grain .312 bullets. Rifles bore was slugged and came out to .311.
Started at 48 grains of IMR7383 Lot 40,000 and stopped at 49 grains. At 48 and 48.5 grains I had two or three granules of unburned powder. At 48.8 and 49 grains no unburned powder. A little sootier than my commercial powders but not too bad. Very little smoke as well and no ammonia smell. I'm sure the longer barrel on the M91 helps to burn the powder better.
49 grains were the most accurate load with a spread of 2 3/8 inches at 50 yards. Taking out the flyer the spread was 1 5/16. I don't have a chronograph, so I proceed very slowly and check every piece of spent brass for excessive pressure after every shot.
Pic here. Next time out I'll go out to 100 yards.
Please use extreme caution working up loads with IMR7383!! If you are a novice stay with commercial powders. In any event don't take any loads you find on the web including mine and not start low and work your way up.
Your results may vary.
Bill