crimping lead bullets

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mohunter55

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I have been reloading missouri bullets 115gr lead 9mm for a little while now. Tonight i did some experimenting with my taper crimp. I know that the dies say to apply 1/8 turn, and work from there. I have also read where others say 1/8 to 1/4 is all that is needed. If i do this, I do not squeeze the bullet, but if i push on the bullet, i can push it into the case pretty easily. If i apply about 3/4 to 1 full turn of the die from when the case just touches it, i have a bullet that will not move back into the case. The problem is, this slightly deforms the bullet by squeezing it in. I have shot these rounds like this for a while now and have not noticed any problems with accuracy. Is it safe to apply 3/4 to 1 turn for crimp even if it deforms the lead bullet? I for sure do not feel safe with only 1/8 turn for the crimp.
 
I believe your problem is in your sizing operation, and not the crimp. It sure sounds like you have insufficient neck tension. With a properly sized case, you should not be able to move the seated bullet even before you apply the crimp. The crimp on a 9mm should only return the case wall back to parallel; e.g. just remove the bell.

Work on your sizing operation until you get a case mouth tight enough so that you cannot move the bullet by hand before crimping. Probably just need to run the sizing die in a little more.
 
Taper crimp dies really don't apply a crimp that holds the bullet, they just remove the bell. Over crimping with a taper crimp die can actually loosen the case around the bullet. Just crimp tight enough to allow the round to chamber reliably.

What I've found was that RCBS sizing dies don't resize the case as small/tight as Dillon dies. I've had the most trouble with Winchester 45 ACP brass. Then I switched to Dillon dies, and all my loose bullet problems went away. Without applying the crimp, you should not be able to move the bullet down in the case by pressing the finished round against the workbench. If you can, your resizer die is probably a bit on the loose side.
 
Sizer is too big, or expander is too big. RP brass is the thinnest, and often times the culprit when neck tension is borderline anyway.

Forget about 1/8, or 1/4 turn etc. Adjust the crimp die to remove the bell, and perhaps a hair more.

Similar thread here
 
the case i was testing was a Federal "FC" stamped. I sill do a little more testing tonight with various brands. I have R-P, WIN, Blazer cases i can also try
 
The 9mm Luger case has a very pronounced taper from front to back.

If the sizing die is not adjusted all the way down almost touching the shell holder, you are not FL sizing the case mouth due to the .011" tapered case.

1. Adjust the die properly. Use a sheet of paper between the die and shell holder and set the die tight against that.
2. Try sizing one and measure the inside case mouth before belling/expanding.

If the case mouth is .002" - .003" less then bullet diameter before expanding, your expander is too big.
You can reduce the diameter by chucking it in an electric drill and using emery cloth on it.

rc
 
Not if the case neck tension isn't right in the first place.

Taper crimping with the standard seating die, or the FCD, cannot correct improper neck tension to start with.

rc
 
well, i got home and did some experimenting tonight. i believe my problem was just with 1 fc case that i was using. i did not have the problem with other cases. once i figured this out, i decided to play around with some .45 acp lead reloads. I have posted on here before about having problems with my rounds fitting my case gauge (dillon). Tonight i began experimenting with my crimp. I began adjusting the crimp until the round slid into the case guage. I couldnt believe it...this is the first time ive gotten a lead round to fit into the case gauge. I guess that before i was always applying way to much crimp, which was bulging the case slightly just behind the bottom of the bullet. I had read some where that you want to be able to see a small shiny ring around the mouth of the case from the crimp...i guess that was wrong. My new strategy will be to just get the case to where it fits the case gauge, which ends up being just a very slight crimp...to where i can just feel it bearly crimp the case. my crimp measures .471 for my lead reloads...does this sound about right?
 
alright, i spent a few more hours messing around. What i found is that random federal brass, stamped FC that i have is junk. The neck tension is aweful and it will not hold. I went ahead and ordered a egw undersize dies for 9mm, 40s&W, and 45 acp. I plan on reloading for 40 soon, and i figured why not give them all a try. It will give me peace of mind at least having that extra .001. I will post an update on my results.
 
Lee FCD. Very simple answer to most all problems dealing with rounds that headspace on the case mouth.

I use FCD's for all the calibers I load but don't believe in using it to fix problems. FCD is not the answer for a loose bullet. It's a sizing issue.
 
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