westernrover
Member
- Joined
- May 4, 2018
- Messages
- 1,613
I normally roll-crimp .357 in the cannelure or even force a roll-crimp into a soft bullet without a crimp groove. Sinterfire's manual cautions against roll crimping, denting or deforming the compressed powdered metal bullets:
"Very little taper crimp is required, less than cast, jacketed or plated bullets. Prior to finalizing the set-up of the loading operation, the bullets of several loaded rounds should be pulled from their cases and inspected for crimp compression. A properly crimped bullet should not show signs of crimp compression or indentation by, or at the case mouth."
Again, I normally roll-crimp, but I believe I can taper-crimp with my Lee bullet seating die. According to Lee's instructions, the die is to be screwed in until it touches the shell-holder, then backed out three full turns (plus an additional two turns for 357 Magnum). The instructions indicate it can be screwed in further for an increasing degree of crimp. I found testing an empty case that it must be turned-out nearly four full turns before it won't crimp the case. If I have it backed out 3 and 2/3rd's turns, it will just taper the mouth of an empty case.
If I try to seat a bullet at that setting, the case will slightly buckle. I see that if I try to crimp a flared mouth without a bullet it buckles. But I can push a resized case that is not flared into the crimping part of the die. I've tried to minimize the flare or mouth expansion as much as possible. Still, I get case buckling below the bullet unless my die is backed out at least 4 full turns where I cannot see it is crimping at all.
If I had a bullet puller, I could increase the crimp until I saw some damage from compression or denting and then back it off until it no longer damaged the bullet. But it seems to adjust the die for any amount of taper crimp results in damaged cases.
Should I just load them with practically no crimp and just the tension from the resized case?
They'll be fired from a heavy gun and I'm not too concerned about crimp jump, but I do intend to use a ball powder that works best with a strong rolled-crimp when using cast or plated bullets. I'm hoping the hard Sinterfire bullet will give me a little more start pressure than cast, but if I can't get a consistent burn then I have a flake powder I can fall back on.
I only have 2000 of these to load and I'm hoping to avoid as much waste as possible.
"Very little taper crimp is required, less than cast, jacketed or plated bullets. Prior to finalizing the set-up of the loading operation, the bullets of several loaded rounds should be pulled from their cases and inspected for crimp compression. A properly crimped bullet should not show signs of crimp compression or indentation by, or at the case mouth."
Again, I normally roll-crimp, but I believe I can taper-crimp with my Lee bullet seating die. According to Lee's instructions, the die is to be screwed in until it touches the shell-holder, then backed out three full turns (plus an additional two turns for 357 Magnum). The instructions indicate it can be screwed in further for an increasing degree of crimp. I found testing an empty case that it must be turned-out nearly four full turns before it won't crimp the case. If I have it backed out 3 and 2/3rd's turns, it will just taper the mouth of an empty case.
If I try to seat a bullet at that setting, the case will slightly buckle. I see that if I try to crimp a flared mouth without a bullet it buckles. But I can push a resized case that is not flared into the crimping part of the die. I've tried to minimize the flare or mouth expansion as much as possible. Still, I get case buckling below the bullet unless my die is backed out at least 4 full turns where I cannot see it is crimping at all.
If I had a bullet puller, I could increase the crimp until I saw some damage from compression or denting and then back it off until it no longer damaged the bullet. But it seems to adjust the die for any amount of taper crimp results in damaged cases.
Should I just load them with practically no crimp and just the tension from the resized case?
They'll be fired from a heavy gun and I'm not too concerned about crimp jump, but I do intend to use a ball powder that works best with a strong rolled-crimp when using cast or plated bullets. I'm hoping the hard Sinterfire bullet will give me a little more start pressure than cast, but if I can't get a consistent burn then I have a flake powder I can fall back on.
I only have 2000 of these to load and I'm hoping to avoid as much waste as possible.
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