Powder Questions

462

California's Central Coast Amid The Insanity
Trivial powder trivia questions:
Anybody know the meaning of IMR's numbering system?

Similarly, what does WC signify? WC 842, WC 860, etc.
 

RBHarter

West Central AR
WC I believe is Winchester profile based . I'm not certain and that may not be even close but Win/Olin ammo is under the same roof with FC and CCI with the Lake City contract . At least I think that's right .

Most of the IMR numbers get bigger as they get slower and DuPont came up with them . They were doing mostly explosives and it is likely an indexing of additives , shape , and perfections to the base . Based on my limited experience with GI AA&E and component reference .
 
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fiver

Well-Known Member
Alliant is under the ATK banner which is Federal and Lake city and now CCI too.
they just had a re-bid on the Alliant contract and it was supposedly going to change hands.
this means little to us as consumers since it will still be made in the same place by the same people, but it could affect the price.
 

462

California's Central Coast Amid The Insanity
Easy to see that the numbers go from fast to slow, and I figured they might have something to do with their chemical makeup, still my trivial mind had to ask.

So, WC = Winchester Contract? Okay, makes perfect sense. They all would also be Ball(little trademark thingie goes here) powders, too?
I once stomped off/pried off a 20 mm projectile* and poured a round powder on and about the flightline. First time I'd seen round powder.
*Air Force: smaller than .50 caliber is a bullet, .50 caliber and larger is a projectile.

That brings up another trivial question: Assuming the item is a "bullet", what's with tip, head, slug, projo, etc.?
 
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Brad

Benevolent Overlord and site owner
Staff member
Pill is my least favorite.

I also love bullets are a term for loaded rounds. I can‘t people to understand that a bullet is the projectile. The loaded round can be called ammunition but the bullet is a component of the ammunition.

Maybe we should start calling our cars a tire.
 

Glaciers

Alaska Land of the Midnight Sun
Man you guys are bored.
All right, if you're caught up in the loading room, invent a new wildcat, resurrection of and old wildcat or obsolete cartridge might be in order.
You know, draw plan, research, root around in the safe find that rifle all the way in the back, blow the dust off and start planning.
Well there's a new or used barrel on eBay.
Or get all of your scoped rifles out and remove the scopes and switch them from one rifle to another. Then you get to sight them in again.
 

RBHarter

West Central AR
Probably to bypass filters on S&M.,....social media sites ......
4831 was the original 20mm cannon powder .
 

Spindrift

Well-Known Member
I think one of the loads for the 20mm Oerlikon was 400grs of 4831, with a 2000grs projectile (if some of you happen to have an Oerlikon cannon laying around). Supposedly, it made 2800fps.
 

RicinYakima

High Steppes of Eastern Washington
IIRC, the DuPont story is that 4831 was the first powder to be stopped as soon as the war was over, as in days. There was more 20MM Oerlikon fired from January thru August 1945 than the rest of history. That is why Hodgdon started selling it first. The last to go out of production was 4895.
 

Ian

Notorious member
IIRC Ken picked "boolits" because "cast bullets" was already owned by another web entity.

"Pill" is also my absolute most hated component slang term.

John G, yeah, I was up past midnight working out a .30 Badger insert for one of my 16-gauge shotguns. Really wanted to turn an insert for my NEF .45 Colt but the .38 case is just too big. Could do a .32 H&R or .22 rimfire for it though. What I REALLY want is to make a new barrel off of a stub for the Badger and pin/weld a muzzle brake at 16.5" to knock another couple inches off the suppressed length.
 

462

California's Central Coast Amid The Insanity
An Internet search turned up American 20 mm ammo is loaded with WC 870 or WC 872, a double base spherical powder. The article didn't give a date that either of the powders were first used, but I know that the 20 mm M-39 aircraft cannon was first tested in the F-86 toward the end of the Korean War. By that time Ball powder had been well tested and proven.
Anyway, and as Ric mentioned, Joyce Hodgdon bought all the remaining 4831 inventory, or at least several train cars of it.

Of the many millions of 20 mm I loaded, both HEI (high explosive incendiary) rounds in Viet Nam, and practice rounds once back in the states, the one I opened was a practice round.
 

RicinYakima

High Steppes of Eastern Washington
You are right! The 20 MM loaded for aircraft loaded to different specifications than the Navy WW2 defensive Oerlikon. You can't rack the cannon in the airplane while it is flying very easy! Did they make automatic systems in the jets? DuPont single base powders took six weeks to make from start (soaking wood linters in nitric acid) to the finished product. Winchester could make double based powder in two weeks with nitroglycerin. The trade off was making the nitroglycerin. That is where the "save the cooking grease" campaign in WW2 came from, you had to have animal fat to make glycerin. Once the military totally converted over from corrosive primers in 1954, ball powder became the norm. All M1 carbine ammo is loaded with non-corrosive primers and ball powders from the very beginning.
 

462

California's Central Coast Amid The Insanity
Did they make automatic systems in the jets?
The M-39 -- nothing more than a massive five shot revolver -- needed to be manually charged by the weapons mechanics. Two rounds were cycled into the cylinder on the flightline when the ammunition was loaded, and the third cycle which put the first round into firing position was done at the arm end of the runway.

The M-61 relies on electrics.