Need some quick help please on roll crimp

[pdhunter]

Loading 45 colt - new starline brass -the case length varies in length .008.
Is that too much for the roll crimp ?
Thanks for your help

 

[J Miller]

pdhunter,

Yes, .008" is excessive for a consistent roll crimp. The normal trim to length for the .45 Colt case is 1.280", although some manuals say to trim back to 1.275".
I'd find the shortest case and trim the rest back as close to 1.280" as I could, but not shorter than 1.275". Then load and crimp them.

Oh and I trim after full length sizing. You'll be surprised at how much factory new cases vary in diameter and roundness.

Joe

 

[pdhunter]

Thanks for that information. In this batch of Starline brass on the short end
I have found . 1.272 and on the long end 1.280.
In talking to starline they recommened that I resize down to the seating depth
of the bullet. The measurements I took were after I resized that way.
I guess I'll try and fl resize and see if the strech enough to get at least 1.275
and trim them all to that.

 

[slippingaway]

I would full length size them, and then sort them into two groups, with the division halfway between the shortest and longest. Treat them as two separate batches, and now your variance is cut down to roughly .004 in each batch. Set your crimp die for the first batch and run them through, then adjust it for the second batch and run them through.

I wouldn't bother trimming cases until they've been fired at least once. If you trim them now, once they've been fired you may end up with this exact situation all over again, since I've had new brass both grow and shrink from firing.

To be perfectly honest, if I was loading them up for plinking ammo, I'd just set my crimping die to give an acceptable crimp on the short cases, and let it crimp the long ones a little extra firm. It's not gonna affect accuracy or case pressure enough for me to care. For my hotter hunting loads, I'd take a batch of fired brass, trim with a Lee case trimmer/length gauge, toss any that are too short in with the "plinking" brass, and then deburr and load up the batch which should all now be the same length.

 

[Ruber]

In this batch of Starline brass on the short end
I have found . 1.272 and on the long end 1.280.
In talking to starline they recommened that I resize down to the seating depth
of the bullet. The measurements I took were after I resized that way.
I guess I'll try and fl resize and see if the strech enough to get at least 1.275
and trim them all to that.

that has been my typical experience with starline brass, I just trim to the 1.275 and be happy with the .003 variance. Most of the bullets I load have good cannelures and I still get a good crimp.