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walnutred
03-19-2009, 05:28 AM
I am loading 9x19 and have a question about crimp and headspace. I'm using a taper crimp die but how do I know when i have it right? I adjusted the dies with a factory round in the shell holder, then loosened it up a 1/4 turn. The resulting loaded shell would not chamber properly in my pistol. I adjusted the die until the shells would feed reliably, then tightened it an aditional 1/16th of a turn.

How do I know the headspace is correct and it is not he extractor holding the casing against the bolt face? Is there a standard loaded case mouth diameter? I could find OAL in my manuals but not that information.

cubflyer75
03-19-2009, 07:36 AM
sounds good to me.

factory loaded round probably has longer brass; reloaded round not crimped enough. Measure factory loaded round case mouth diameter, and crimp to that size.

strip barrel and drop into chamber to see if headspaces on mouth...

runfiverun
03-19-2009, 03:36 PM
if your cases are the same length and stop on the case mouth that is your headspace.
if the bolt doesn't close they[the cases] are too long.
if you continue to squeeze them too far, the case is entering the throat not stopping in the chamber.
what you was doing was flattening out the case flair till it slid all the way into the chamber.

walnutred
03-19-2009, 04:08 PM
I'm using the old Lyman 356242, 121gn bullet. If I seat the bullet out to the same length as a factory FMJ load the front grease groove is exposed. In addition the bullet is more rounded than a FMJ load and the bullet seems to hang up on the chamber wall and not let the slide go into battery.

I am seating the bullet so that the case mouth splits the front driving band. This is slightly shorter than a FMJ load but functions fine once the crimp die is adjusted. Like I mentioned, I adjusted the taper crimp die until the slide would go into battery from the locked back position, then tightened it a 16th of a turn more to allow for fouling. Everything feeds and functions fine, my concern is that if my crimp die is too tight I may be putting undue strain on my extractor.

I'll measure the case mouth on a loaded factory die and see how close I am. Probably worrying over nothing.

Calamity Jake
03-20-2009, 10:56 AM
I use the same boolet. Seat to Lyman cast bullet manual OAL and check for function. Adjust OAL from there.

Taper crimping for jacketed and cast are two differant games because the profiles are differant. After setting OAL for cast, taper crimp enough to remove flair plus 1/8 turn, check for function, adjust if needed and call it good,

Unless you trim all brass to the same OAL you will not get them them to head space on the chamber mouth, and then they may not anyway until you can find a good way to measure the length of chamber in your gun which is going to be longer than the stated max OAL of the case, thats just the way the factories make them.

Measure a hand full of your cases, if they are under max OAL, deburr case mouth ID and OD, load them and be done with it.

walnutred
03-20-2009, 12:43 PM
That makes sense Jake. I'm using mixed brass, so I'm sure they are not all the same length to start with. 45 ACP and others I've loaded for decades, just never loaded 9x19 before. So I guess I'm making it too complicated. The load I'm using is 3.5 gns of Bullseye, which is the "accuracy" load in my old Lyman 45 manual for this bullet. That load is also not pushing the envelope by any means but shoots to point of aim for me and makes a good practice load.