Re: Are .40S&W and 10mm dies interchangable?
The 10mm is longer than the 40. Same as the 357 is longer than the 38 special. I've found that if a manufacturer makes a set of dies specifically for the longer case, it usually will not crimp the shorter case. For example, my first set of dies was RCBS 357. Crimping shoulder would not work with 38 special. So I bought a 38 special seating die. It works with both of them. If you buy a set marked 38/357, it will work with both.
The 40 S&W dies will work with both 40 and 10, but the 10mm crimping die may not work with the shorter 40 case. However, if you do buy the 10mm dies, and find they will not crimp the 40 brass, all you need to do is get out your sidegrinder and take a little bit off the bottom of the seating die. That will allow you to screw it into the press farther, and make the crimping shoulder lower, so it will work with the 40s.
I had to do this. I have a set of 44 Magnum/44 Special dies. Problem is, I was using them to load 44 Russian. Had to shorten both the belling die and the seating die. Now they work for all three calibers.
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