roll crimp question

deguello · May 1, 2000, 02:05 PM

I'm a brand new reloader with a single stage press, I'm trying to load 250 gn lead bullet in .45 colt with a rcbs carbide die set. I'm going by the written instructions and pictures, and I'm not sure about my results. On the expander die, I'm just flaring the very end of the case enough to set the base of the bullet in it. I'm pretty confident about that, but as far as seating and crimping I have no idea how i'm doing. It doesn't look like the crimp on store-bought bullets, it just looks like something in the die is catching the top 1/16 inch of the case. Also, if I put about 50-60 lbs of pressure on it, the bullet will start to push into the case. Does that mean a bad crimp, or is that too much of a stress test. (by the way, there's no powder in the ones i'm testing)

Mike / Tx · May 1, 2000, 03:53 PM

Deguello,

First off if your die set doesn't specify that the crimp is a roll then it is most likely a taper crimp. On a roll crimp die you generally will get a nice little radius at the top of the case around your bullet. These aer good for lead bullets. If your getting the flattened look on your test cases then your taper crimping them. This will work but tends to do better on the jacketed bullets with the cannalure. I would suggest that you try to seat and crimp in two seperate operations and when you seat your bullet set it so that you are catching just below the lip of the driving band. If your bullet has got a crimping grove on it then just enough to completely compress the case into it should be suffucient. There is such a thing as too much crimp and you should adjust your crimp die so that the very top of your stroke is the end of the crimp.

I'm sure that others will join in and cover some finer details but this should help you get a better idea.

I hope this sheds some light on your situation.

Mike / Tx

May 1, 2000, 02:05 PM	#1
deguello Member Join Date: September 12, 1999 Location: tx, usa Posts: 43	I'm a brand new reloader with a single stage press, I'm trying to load 250 gn lead bullet in .45 colt with a rcbs carbide die set. I'm going by the written instructions and pictures, and I'm not sure about my results. On the expander die, I'm just flaring the very end of the case enough to set the base of the bullet in it. I'm pretty confident about that, but as far as seating and crimping I have no idea how i'm doing. It doesn't look like the crimp on store-bought bullets, it just looks like something in the die is catching the top 1/16 inch of the case. Also, if I put about 50-60 lbs of pressure on it, the bullet will start to push into the case. Does that mean a bad crimp, or is that too much of a stress test. (by the way, there's no powder in the ones i'm testing)

May 1, 2000, 03:53 PM	#2
Mike / Tx Senior Member Join Date: April 8, 2000 Posts: 2,101	Deguello, First off if your die set doesn't specify that the crimp is a roll then it is most likely a taper crimp. On a roll crimp die you generally will get a nice little radius at the top of the case around your bullet. These aer good for lead bullets. If your getting the flattened look on your test cases then your taper crimping them. This will work but tends to do better on the jacketed bullets with the cannalure. I would suggest that you try to seat and crimp in two seperate operations and when you seat your bullet set it so that you are catching just below the lip of the driving band. If your bullet has got a crimping grove on it then just enough to completely compress the case into it should be suffucient. There is such a thing as too much crimp and you should adjust your crimp die so that the very top of your stroke is the end of the crimp. I'm sure that others will join in and cover some finer details but this should help you get a better idea. I hope this sheds some light on your situation. Mike / Tx