Do i need a crimp die for .38/.357

[foolproofoak]

I'm new to reloading, and i was just wondering if i needed a crimp die for .38/.357 mag. loads. For my autos i bought the 4 die lee sets, but for my .38/.357s i got the RCBS set that only had 3 dies, but i can't find an RCBS crimp die and was wondering if this was a necessity. Thanks for the help.

 

[foolproofoak]

I'm new to reloading, and i was just wondering if i needed a crimp die for .38/.357 mag. loads. For my autos i bought the 4 die lee sets, but for my .38/.357s i got the RCBS set that only had 3 dies, but i can't find an RCBS crimp die and was wondering if this was a necessity. Thanks for the help.

 

[signsrup]

I have an RCBS 3 die set for the 38/357, and the crimp function is performed with the die-body of the bullet seating die. It works with bullets with a crimp groove or cannelure.

If you're loading bullets that require a taper crimp, then you will need an additional die, but it doesn't have to be RCBS manufactured.

 

[FrankD45]

Yes, you should crimp .38/.357 cartridges. The crimp is needed to prevent bullets backing out under recoil and locking the revolver. The degree of crimp is determined by the power of the load. In other words a hard crimp for full magnum loads and a lighter crimp for mid-range loads. These die sets typically include a combination seater/crimp die that seats the bullet and applies the appropriate crimp. Many reloaders use the Lee Factory crimp die instead of the standard crimp die as it also re-sizes the cartridge and allows greater consistency.

I hope that helps,

Frank

 

[Steve C]

IMO you don't need a separate crimp die for straight walled roll crimped revolver cartridges like the .38/.357 mag as the combination seating and crimping die that comes with the 3 die set works fine. The post sizing of the Factory crimp die isn't as useful for these cartridges.

If you want to crimp in a separate stage with the standard die you simply back it out a turn so it doesn't crimp on the seating operation then back out the seating stem and adjust it down to crimp when you run the cases with bullet seated back through.