.38 Special loading question

[Nogoodnik]

First time to the forum and new to reloading. I've loaded some Starline .38 Special brass with 5.7 GR Unique and Hornady 38 CAL .357 125 GR FP/XTP bullets.

In looking at my reloading manual, there does not seem to be a crimp diameter listed - as though the crimp should be the same measurement as the cartridge diameter near base.

I put a slight crimp in - fired one and just one through my old S&W 620 (.357 Mag) and left the bullet in the barrel. That problem is solved - but I am concerned about all this. I've loaded some beautiful .45 ACP cartridges, but have trouble with the .38 Specials.

I started at a seating depth of 1.55 (I believe it is the Max O.A.L. When I give it a very slight crimp, the bullet turns in the case. I am afraid of over-crimping.

Kindly offer some advice. How deep can I seat the bullets?

Also, I've measured some different factory .38 Special cartidges, and there seems to be a difference in diameters. If I measure my case - in this instance Starline - should the crimp be a certain percentage, or degree down from that measurement?

I don't want to have to remove another bullet from the barrel. Do you think I had a bad primer? It looked detonated to me.

Excellent forum pages, by the way!

[chirpy]

Did you roll crimp in the crimping groove or taper crimp? A good roll crimp should not let the bullet move. An insufficient taper crimp might. Roll crimp for the most part are meant for revolvers and taper for semi autos. It sounds like you didn't get proper powder ignition due to insufficient crimp. I don't know where you got the powder charge but it seems OK but I can't say 100%.

[wide45]

New brass? if so, you still need to run it through the size die.

Check that the belling die does not over expand the sized brass. You want some bell so the bullet will sit there, but you should not be able to shove it into the case by hand.

Are you using the Lee factory crimp die? I once saw it cause a problem like this.

[chirpy]

Just thought of something else...check to make sure your expander button (on the belling die) isn't too big. You might need to turn it down some.

[revchuck]

Disregard the max OAL - it's not relevant for revolvers 99.99% of the time. You don't have to worry about feeding from a magazine. BTW, the max OAL is 1.59".

Most jacketed (and cast) revolver bullets have a crimp groove. You seat the bullet until the case mouth is in the middle of the crimp groove and roll crimp the case mouth into the groove - not a bunch, because you can distort the round, but enough to see it. Most .38 Special ammo will come out to about 1.45" OAL when the bullet is seated this way. Load data is worked up with the bullet seated to the crimp groove, so varying much in either direction can do strange things to load pressure.

Make sure you full length size new brass!

[MARKAVELI]

What is the difference between role and taper crimp?

[Bubber]

What is the difference between role and taper crimp?

From what I think I know (which ain't much) a roll crimp is done on the seating die by adjusting the whole die down just far enough to "feel" the restriction in the die on the brass. Adjust you seat to proper OAL desired. As I have a fourth staion on my press I taper crimp my Revo ammo. It may not be necessary but I skip the roll crimp to taper crimp. But if loading on a three position press and on sigle stage presses a roll crimp will take away one step in the process. Just my thoughts.

Nogoodnik as wide45 alludes to the crimp does little to hold the brass and it is the sidewall of the case that hold the bullet. With a roll crimp there should not be a problem. But too much on the tapercrimp will resize the bullet smaller and while the brass may return to the original size the lead in the bullet will not causing it to be undersize. Again this info is worth what you paid for it...Later rdd