sikacz wrote: Sun Apr 11, 2021 3:34 pm
jbjh wrote: Sun Apr 11, 2021 3:14 pm
Gotcha. Was mostly trying to illustrate that die makers have lots of SKUs and to make sure it’s the one you want. Descriptions are nice, but SKU is final.
Sent from my iPhone using Tapatalk
I’m here to learn, so any info is welcome. The 38 Special is a round I’ll probably load a lot more than others. Are roll crimp and taper crimp sets totally different or are there parts of the three the same?
The vast majority of what I reload is .38 Special, followed by .45 Colt, which is the exact same process.
First, any .38 Special die set can also reload .357 Magnum.
Second, roll crimps and taper crimps are simply a matter of degree. Here's what a roll crimp looks like. The left round is the clearest in the image.
Primarily, a roll crimp is done for tube-fed leverguns to prevent the bullet from getting knocked a bit further back into the case ("bullet set-back") by the momentum of the other rounds after you fire and work the lever. Remember that back in the day when the .44-40 was invented, it was used in both revolvers and Winchester/Henry lever rifles. People routinely used the same ammo for both handgun and rifle. Roll crimping also has a small effect to keep the bullet from getting pulled out of the case a bit under heavy recoil, for example, in a .44 Magnum S&W Model 329 or a .454 Casull, though case neck tension is the bigger factor there.
Note that using a roll crimp depends on your bullet having either a crimp groove (cast lead bullets, like what I use) or a cannelure (jacketed bullets).
A "taper crimp" is actually not really a "crimp" at all. It's merely a straightening out of the case mouth after you've belled (or "flared"--both mean the same here) the case mouth for the bullet-seating step. We do this with certain cases because, unlike rimmed revolver cases like .38/357 and .45 Colt, the 9mm Parabellum actually headspaces on the case mouth. So do the .45 ACP, .40 S&W, .357 SIG, and quite a few others. Therefore, the case mouth cannot be roll-crimped on those cartridges, because otherwise you mess up the headspacing. That's why all we do is re-flatten out the belling and no more, with those cartridges.
Taper crimps are also used with jacketed bullets that don't have a cannelure. This is so you don't end up cutting a groove into the bullet and thus damaging it. I've seen a lot of factory ammo, which used jacketed bullets, use taper crimps for this very reason.
That's the difference.
So, for your .38/357, it depends on the style of bullet that you're using. If you have a crimp groove or a cannelure, then roll-crimp. If not, then taper-crimp.
With my Lee 38/357 die set, I've done both roll crimping and taper crimping, just as an experiment. I settled on a moderate roll crimp for my cast bullets because they do have a crimp groove, as you can see in the picture. If you roll crimp, that's about how you want it to look.
"San Francisco Liberal With A Gun"
A true Liberal must
back the Second Amendment 100%!