crimping your 9mm?

[Arrdy]

... Leading is the buildup of lead in the bore that happens in nearly all firearms firing high velocity lead bullets. ...

Go back and read my posts .... I keep the lead loads at a lowered velocity to avoid lead fouling. I also use HARD lubed lead bullets from Hunter's Supply.

If you need a copper coated bullet, look at the Rainer line. I use their 9mm, 38/357 and 40S&W with good results.

[william lotts]

this thread just answered part of another post i made yesterday. Being new to this forum, i wondered why the OAL of the reloading manuals vary all over the place for different loadings in 380, 9mm and 40 cal cartridges. IF they headspace on the rim it makes no sense, However, if they headspace on the extractor, then i understand how different OAL can work in the same gun.
BUT that does not answer the question: why different OAL's for different projectile weights in the same caliber. What is the determining factor?

GREAT FORUM thanks a bunch. william

[max384]

this thread just answered part of another post i made yesterday. Being new to this forum, i wondered why the OAL of the reloading manuals vary all over the place for different loadings in 380, 9mm and 40 cal cartridges. IF they headspace on the rim it makes no sense, However, if they headspace on the extractor, then i understand how different OAL can work in the same gun.
BUT that does not answer the question: why different OAL's for different projectile weights in the same caliber. What is the determining factor?

GREAT FORUM thanks a bunch. william

The minimum OAL is determined by measuring chamber pressures. The max. OAL is as long as you want it to be, so long as it still fits into the chamber and/or magazine and there is enough neck tension on the bullet (as far as I know anyhow).

A heavier bullet will be longer than a shorter one of the same caliber, assuming the same bullet shape. If it is seated to the same OAL, then the seating depth would be increased (which would increase pressures ). If the seating depth is kept constant, than the OAL will be increased. However, the OALs can jump all over the place as you move up or down in weight. This is mainly because of differences in bullet shapes. For example, a 180gr flat nose bullet may produce a shorter OAL than a 135gr round nose of the same caliber. However, they would still be seated to roughly the same depth.

^^^The above is based upon keeping the seating depth constant. There may be more involved, such as hardness of the projectiles (lead vs. jacketed), concavity of base of bullet, nonlinear pressure vs. seating depth of different weights of projectiles, etc. However, this is the basic idea of it.

[Suburban]

9mm uses a taper crimp because it headspaces on the case mouth. A simple 3 die set will be all you need.

+1

I stopped using the LEE FCD die for 9mm about 12,000 rounds ago. I use once fired range brass, submachinegun brass, and lots of "Glocked" brass. As long as the brass isn't cracked, and doesn't have crimped in primers, I'll reload it. My ammo even drops right into the chamber of the KKF match barrel. I use the LEE seating die to iron out the flare.

No problems with .45ACP and Kart Match barrel either. No FCD. The Glock .45ACP chambers ARE NOT fully-supported, they DO bulge brass, but the LEE sizing die takes care of it.