IMR 7383

[Cornbelt]

  I have a good bit of surplus IMR 7383 (as in pull-down .50 cal) which is so bulky it won't work well in small cases, but works best in high volume small bullet ctgs like .25/'06 or .22 Swift. I got it thinking I'd use it for .22/.250, as there are a couple in the family.
  The source I got it from in Owensboro, KY is quite reputable and has used it himself for his own .25/'06. He told me he uses data reduced 15% from IMR 4831 as a starting point. The biggest problem is in getting enough powder in the case to get the velocity up to where it belongs, (7lbs to gal instead of the usual eight) so .308 is out of the question.
  I'm looking for someone with experience using this powder to chime in here.
  I know it works on .50 BMG, gut I'm wanting info on stuff a little more conventional. 
   Anyone use it for reduced loads using cast bullets in .308 or similar?
   What about 6mm shooters?
 
 Anyone?

[AtlLaw]

Interesting...     I wonder how it would work in my 50-140?   

[Cornbelt]

 I don't know. Have any data for IMR 4831 in that cal?
 CTGs of the World is the only place I've found .50-140 info and the only IMR pdr listed is 4198.

[Larry L]

I think you have a typo in yer post. The powder you most likely have is IMR 7383, not 7883. If so, it's probably one of the most dangerous powders you'll ever load and frankly, should never be available to reloaders. But it can be used as a powder for medium to reduced loads with some success but it can come at a price. The biggest issue for reloaders is that the powder is spikey. You can develop a load that seems to be just fine with zero issues and then Kablooey! It can go from fine to extreme pressure with almost no changes like seating a bullet less than hair deeper or possible bullet movement while riding in the gun, bullet being seated deeper when chambered, or too much or inconsistent neck tension/crimp. Pressure build in a lot of cases is extreme by comparison to what is normally available to reloaders- this is NOT normal powder. It is a triple base powder with an additional flash suppressing detergent called Nitroguanidine. As the detergent burns it creates ammonia gas so be aware of it. If you intend to use it, I'd suggest using the data for IMR4064 for starting loads and work towards IMR 4350 but NEVER load a max load of it using IMR4350 data. About midway at best. If you are expecting great velocities out of it, be prepared to be disappointed. It'll produce medium velocities at best before it spikes without warning. You'll also find it is extremely filthy and that's from the flash suppressant. Frankly, I'd strongly suggest using it as fertilizer. My life and guns are worth more than this powder....if it's IMR 7383. YMMV.

[Old Syko]

I think you have a typo in yer post. The powder you most likely have is IMR 7383, not 7883. If so, it's probably one of the most dangerous powders you'll ever load and frankly, should never be available to reloaders.

Because of the noted statement you lost any credibility with me.  The reality of things are that it is a fairly good powder for it's intended purpose.  Jeff Bartlett claims reasonable success in a 25-06.  I couldn't verify that as fact but Jeff has no reason to make false claims since he does sell the stuff.  My only experience with it is in the original 50 cal loading.  That being said, I can see no reason it couldn't be used successfully in a round with the capacity of a 50-140.  And at $8 per pound at today's prices it may be worth a try.

[Cornbelt]

 Yes, it was a typo. And it is 7383. I modified the post to reflect it. Thanks for pointing it out. Also thanks for the information. The more I can get, the better .

[Larry L]

If info is what ya want..... This is not actually pull down powder from what you know as a 50 BMG. This powder was ONLY used for spotter ammo in the M8c Spotter Rifle. The idea was for the ammo to ballistically replicate the 106mm rifle with tracer ammo. The case it self is not near as large as the 50BMG. More like a 308 versus a 3006. Here's a pic for comparison:



It was spotter ammo for this gun:



I don't have the info at hand but any powder used for military tracer ammo is going to burn HOT to ensure ignition of the tracer. Kinda like WC844 versus WC844T which burns about 250F hotter than the standard WC844. It doesn't take long for this hotter powder to have effects on a barrel. Considering there's next to zero reloading data, the characteristics of it makes it spike pressures, I consider the use it dangerous as apparently do others as you don't find much it for sale. There's a reason folks like Hodgdon, who has made a billion dollar business out of pull down military powders, do not have it for sale. It should ONLY be used by folks that have a clue about it, not yer average reloader. If you decide to use it, be EXTREMELY cautious.

[Cornbelt]

 Thanks. The reason I haven't used it is because of the peculiar lack of published data. And that I've got a .22/.250 and not a .25/'06 to copy.  To his credit, Jeff said it was NOT a comprehensive powder. But it didn't cost much and I hoped to find something published for a .22/.250 using a 35 gr V-max. No mach 4 or anything. Just fast enough to make the bullet do what it was designed for. There's a lot to be said for the proper protocol, and I'm just not finding much info.
 
  When I was a shooter in a mine using hundreds of tons of high explosives, we had a protocol that, when everyone followed, made the job absolutely boring. When they didn't, it was a bad day for everyone. Some of that stuff was a tri-nitro compound, so if need be, this stuff might be good for shooting out stumps.