Reloading OGC 9mm brass

[timwarner]

So I got into loading some 9mm, been awhile, just dug it out of my pail and threw it in my loader...

Damn these OGC people shoot hot 9mm. Or, I grabbed out of my "blue brass" bucket that's been wiped clean of the blue from tumbling...

Guess I'll find out.

In hindsight, I don't know why I ever tumbled my 5gal pail of major9 brass, that I knew was more or less junk. But I probably should have labeled the buckets, oops.

[justaguy]

You are going to blow your **** head off.

[Snowgun]

Aren't you the one who warned everyone about loading 9mm from OGC?

[brado]

Aren't you the one who warned everyone about loading 9mm from OGC?

LOL

[timwarner]

Yeah, and I had the sense to sort the "bad blue" brass from the "good not blue" brass into separate pails, but now I have 2 pails and both are clean. No blue.

Musta had a few too many when on a tumbling spree and just did everything. I'm sure it's not mixed because my good pail has been in my loading room while the other was outside, but this spring I grabbed the outside one thinking it was good, since it wasn't blue.

Anyone wanna buy a 5 gallon pail of 9mm brass? 50% chance the primers don't fall out, if you pick the right bucket.

[crbutler]

Depends on the price...

for $5, I will wager....

[TH3180]

I'm in for $10, but can I buy both please.

[timwarner]

No, cause I know one is good, and the other is junk. Primers fall out of half the rounds in the mag when you shoot.

[Seismic Sam]

Actually, the fact that Tim is loading 9mm brass to major power levels scares me a lot less than the fact that he just loads every headstamp he picks up. I posted this before, but I reloaded up some "trash brass" that was ALL uncommon or undesirable headstamps, and the difference in jacketed bullet seating pressure was downright scary. All the way from really tight to practially no pressure at all, and I had to dial up my lee FCD to make sure all this stuff was well crimped. It still shot like shyte in a compact CZ clone 9mm. Conclusion: There is a MAJOR difference in wall thickness of the DOZENS of brands of 9mm ammo out there today. Loading 9mm major ammo with FC, Win, or R-P headstamps wouldn't bother me all that much, but with S&B, and some of the indeciperable stuff (9x19 XXX) I'd rather take a pass.

At some point Tim also said an incredibly interesting thing, in that he was shooting compressed loads with a slow burning powder (for 9mm) to keep the pressure down. He still estimated the pressure at 50K, which I frankly doubt because my 9x23 Winchester loads (which use small rifle primers) run at 52,000 PSI according to the "creator" of that round, and he said that while the 9x23 case would not fail at those pressures, pistol primers WOULD. Conclusion: maybe those 9mm major loads are running lower than that. Without examining Tim's brass in very much detail yet, you'd be hard pressed to tell from the case that it was running as hot as some of the stuff I have found at Oakdale.

Now, at some point I will write a rather long article on the statistical thermodynamics of what's going on in a pistol or rifle case when it ignites, but for now I'll just skim the surface with the idea of a compressed load of slow powder versus an uncompressed load of faster powder. With the uncompressed load, the total amount of powder will determine the max pressure, because it's pretty much all going to burn at once with the bullet just leaving the case. Thus the explanation why a double charge of Titegroup in a 40 caliber Glock can wreck the whole gun. With a compressed load of slow burning powder, however, that may NOT be the case, as the powder is tighly compressed and has to burn from the back of the case to the front at whatever burn rate the powder has. In this case, it's the burn rate that may determine the max pressure, and NOT the total grains of powder. To take this to the ultimate level, imagine loading a 9mm case chock full of H1000 and smooshing the bullet down on it. If the powder ignites (which it may not), it's likely that the powder won't finish burning before the bullet leaves the barrel, and you may have one hell of a muzzle flash, and a rather unspectacular velocity for the bullet, regardless of how much powder you put in the case.

To restate, with compressed powder loads (particularly with ball powder where there is very little free space betaeen the powder grains) the burn rate rather than the total powder load may detarmine the max pressure you see.

[timwarner]

Something to keep in mind, Sam, with slower powder the pressure is still building til the bullet exits the barrel. So it may not be 50k initially, by the end of 8.8 grains of burn time with HS-6, it may well be. Someone sent me a program once to figure the pressure, that's where I got the figured case pressure from.
I'm sure you could extrapolate some better info using some pressure curve data and loads compared to what I'm using, but I'm just going off the cuff.
it runs well in my gun, and that's all I care about.

I have severely blown out cases before, I think I still have one. It was a remington case, not a random no name.
9x19 is a hearty case, and can handle more than most would think. But don't shove in 10gr of HS-6, and fire it without a ransom rest.

Either way, resizing this brass is a bitch.

[Seismic Sam]

Based on your resize force, I'll amend my beliefs to thinking that maybe you are getting up to 50K of pressure. Still think there may be something to the burning rate in a compressed load, and to go to an entirely different example that has no relevance here, when I'm shooting my .338 Ultramag, the hottest point on the barrel is fully halfway down its 26" length. In this case, I suspect the Federal 215 primer ignites the Retumbo, the pressure spike compresses the rest of the Retumbo against the bullet with incredible force, and then the slug of powder burns from bottom to top.

A lot of this came from the rather obscure MacMillan 50 FatMac described in Cartridges of the world, and this is a 20mm case shortened and necked down to 50 caliber. In it's description, it states that the case uses forward ignition like artillery shells, which greatly aids accuracy and consistency. In other words, there is a tube going from the primer hole in the case to just below the base of the bullet, and when you pull the trigger, the powder starts burning at the TOP of the case, and the resulting pressure tightly compresses the rest of the charge as it burns down to the base of the case. From a statistical thermodynamic standpoint, this is an optimum configuraition to remove random variations from the burning rate of the powder, and it's been proven to work with the FatMac and also artillery shells.

To repeat: heavily compressed powder loads remove significant variability from the process of powder burning in a confined area like a cartridge case.

[IKMTU]

Go Google OKH Duplex flash tube, I remember reading of this a long time ago......Either in American Rifleman or other magazine.

[hydraulicman]

I thought my 6.4 grains of power pistol behind a 115 fmj was hot.

[1911fan]

It is for precisely the reasons Seismic says.

[ijosef]

Huh. Most of the guys I know at my club shoot powder puff loads. Maybe there's a club for loading hot and a club for loading down.