While loading some ammo for my 40-65WCF with RCBS "Cowboy" dies, I found that the seating stem was too long to seat 400 gr. bullets with the die adjusted to crimp. OK, so we'll just shorten the seating stem! I got to thinking, why not modify the seating stem to accept Lyman/RCBS top punches? (normally used in Lyman/RCBS lubrisizers.) This means you can match the shape of the bullet perfectly with the seating stem by using the appropriate top punch.
First, using a parting tool, we cut the stem 1/8" past the threads.
Then, we drilled a hole 19/64" in the base of the stem to correspond with the diameter of the top punch:.265"
Then, a #21 drill for the threaded setscrew (#10-32) to hold the punch in place.
Lastly, we turned down a shank on the original piece of stem that we cut off, to use in the original seating stem, effectively shortening it by 1/2"
No more damaged soft lead bullets! Now, all that's left to do is find a short setscrew and turn down the shoulders on the top punches and "Bob's your uncle!"
PS: I had to grind a flat spot on the punch in order to get the setscrew below the threads. Also might have to turn down the shoulder(s) on the larger top punches, as well.
First, using a parting tool, we cut the stem 1/8" past the threads.
Then, we drilled a hole 19/64" in the base of the stem to correspond with the diameter of the top punch:.265"
Then, a #21 drill for the threaded setscrew (#10-32) to hold the punch in place.
Lastly, we turned down a shank on the original piece of stem that we cut off, to use in the original seating stem, effectively shortening it by 1/2"
No more damaged soft lead bullets! Now, all that's left to do is find a short setscrew and turn down the shoulders on the top punches and "Bob's your uncle!"
PS: I had to grind a flat spot on the punch in order to get the setscrew below the threads. Also might have to turn down the shoulder(s) on the larger top punches, as well.
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