Any reason NOT to roll crimp my Short colt loads

[3gunnah]

I recently started playing with short Colt loads in my new 627. I have set up the dies so that I am able to use a roll crimp in a Lee Factory Crimp Die. I noticed a lot of guys on here are using 9 millimeter taper crimp. Is there a reason that is done or is it just for convenience. I seem to be having great luck and good accuracy with 3.4 grains of tite group and a Berrys 158. I have not chronographed the load yet but it feels good and extracts well.

[revoman]

My thoughts are all revolver rounds should use roll crimp when fired in a revolver after all a revolver is like a bullet puller that uses inertia to pull the bullet out of the case. Roll crimp is all I have ever used in 38 Short Colt. I am sure others will chime in on why they use taper crimp.

[BallisticianX]

Roll crimp is best suited for jacketed bullets with a cannelure to crimp into. It is a more aggressive crimp that is more effective to firmly secure the bullet to the case to resist over all length (OAL) changes with heavy recoiling magnum calibers. Some older lead bullet designs have a crimp ring that was designed for roll crimps. Back in the early days of law enforcement and military use of revolvers the roll crimp was used with lead bullets to remove any edge of the case mouth to enhance smooth reloading. A roll crimp will shave lead as cast bullets leave the case. In the case of plated bullets like your using a roll crimp is not the wise choice. The aggressive nature of the roll crimp will cut into the thin copper plating causing separation issue with negative results for accuracy. A light taper crimp is a much gentler choice for lead cast and plated bullets. I have a wadcutter load for my model 14 that I originally roll crimped and shot pretty good. I noticed a bit of leading but not to horrible. When I decided to try a taper crimp on that same load my groups tightened up and leading the bore was reduced. I also experimented with roll crimp on plated bullets with unsatisfactory results in accuracy and got leading with separation. Berry's as well as every other plated bullet manufacturer tells you to us a light taper crimp for these reasons.

Edited March 20, 2015 by BallisticianX

[BallisticianX]

My thoughts are all revolver rounds should use roll crimp when fired in a revolver after all a revolver is like a bullet puller that uses inertia to pull the bullet out of the case. Roll crimp is all I have ever used in 38 Short Colt. I am sure others will chime in on why they use taper crimp.

I have never had the bullet OAL disrupted in a revolver due to the recoil with a taper crimp on standard 125ish pf loads. If anything the recoil forces on auto's lends itself to greater chances of OAL change. Especially considering the bullet is slammed against feed ramps that could lead to shortening OAL. All your rimless cartridges commonly found in auto's head space of the case mouth so you have to use a taper crimp. There are no widespread problems with OAL change there either.

[PatJones]

I roll crimp everything I feed into a revolver. I tried taper crimps with plated bullets and a bullet pulled completely out of the case. The Berry's plating is thin, but it will tolerate a light to moderate roll crimp.

[revoman]

At the ICORE Midwest Regional in Tonitown Arkansas I had plated bullets pull out with a taper crimp inside my cylinder. I switched from taper to roll crimp and have never had that problem again. I have used lead, plated, jacketed and coated bullets with or without a cannelure and never have had the problem shaving lead or breaking the plating or coating. Roll crimp works best for me and you should try both and see what works best for you. Remember to roll crimp just enough to hold the bullet and not distort the bullet.

[pskys2]

You can get too aggressive with a roll crimp and plated bullets, but they were a bit more accurate and reduced pulling considerably. BUUUT... don't use a Roll Crimp with Jacketed Bullets unless you have a cannelure, if you do you will run into collapsed and bulged cases. You can get too aggressive with Plated Bullets and Taper Crimps also, so it's just an issue to be aware of.

I tried both with the 160 Bayou's and had better luck with a taper crimp. I've had very little, if any, pull out with them and accuracy is the same. I did have some bulging issues with a roll crimp and the 160 Bayous though.

So, use a Taper Crimp with Jacketed and Lead or moly/poly coated bullets, unless there is a crimping groove or cannelure. Use either with Plated Bullets, just be careful not to cut through the plating.

[PatJones]

When I shot plated, I pulled a bullet after I adjusted my crimp die to check that I hadn't cut thru the plating. I had a pretty good crimp on there with no problem.

[revoman]

It is all about the crimp that you apply whether it is roll or taper and I don't think it really matters what kind of bullet you are using. If you apply to little of either one it does not serve its purpose if you apply to much then you have overkill and you will bulge and deform cases. Remember a crimp is just to hold the bullet long enough for the powder to burn and to give you the velocity that you are looking for. If you want more velocity add more powder do not just rely on the crimp alone to get you there. I don't think ammo manufactures base their velocities on the amount of crimp they put on the bullet. I could be wrong but I don't think so .

The only time I apply a heavier crimp is when I am shooting major 45 ammo or magnum hunting loads and again I do not do overkill just a little more to hold the bullet to get good powder burn. I shoot Precision Delta jacketed 230 grain .45 as my major ammo in in 625 and 1911 and I use a roll crimp. These bullets are FMJ without a cannelure and I have not experienced any problems so far.

[3gunnah]

Thanks guys.