Scuff mark on bullet when seating

coyoteking

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This is a weird one. Loading up 6.5 CM tonight, 140gr Berger Hybrids, and noticed this scuff mark on my bullet, about 3 mm from the case mouth. I cleaned my die with wipeout thinking it may be copper build-up in the die. After cleaning I still had the scuff mark happening. Just for ####s and giggles, I rotated my shell holder 90* in the ram, and fed the cases in from the right side of the press. NO MORE SCUFF MARKS!

Any theories?

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This is a weird one. Loading up 6.5 CM tonight, 140gr Berger Hybrids, and noticed this scuff mark on my bullet, about 3 mm from the case mouth. I cleaned my die with wipeout thinking it may be copper build-up in the die. After cleaning I still had the scuff mark happening. Just for ####s and giggles, I rotated my shell holder 90* in the ram, and fed the cases in from the right side of the press. NO MORE SCUFF MARKS!

Any theories?

View attachment 711605

Sounds like your already have your answer and the solution.
 
It’s a rockchucker press and Forster seater.

Weird. That’s good stuff. Got to be something with that seater. The bullet channel is pretty tight on the Forster seaters. Are you sure there’s not a burr or something in there? I’d send it back, but that’s just me. As other have said, those marks will not affect performance.
 
Check the bullet against the shape of the seater in the seating die. Sounds to me like the seater is for long vld bullets and your bullet shape is rounder. All the pressure is in one small ring.

You can substitute out a different seating stem from another die, if you find a better match.
 
Check the bullet against the shape of the seater in the seating die. Sounds to me like the seater is for long vld bullets and your bullet shape is rounder. All the pressure is in one small ring.

You can substitute out a different seating stem from another die, if you find a better match.

I did check that. You can see the dull mark further up on the bullet in the picture I posted- that’s where the seater is making contact. The scuff mark further down the bullet, closer to the case neck, is a mystery.
 
Weird. That’s good stuff. Got to be something with that seater. The bullet channel is pretty tight on the Forster seaters. Are you sure there’s not a burr or something in there? I’d send it back, but that’s just me. As other have said, those marks will not affect performance.

I’m able to drop a bullet through the channel with no resistance at all. I can’t see any burrs with the naked eye but I’m inclined to agree with you, there must be something in there. I might just send it back for a new one.
 
“I rotated the shell holder 90° and in went away.”
“Got to be something with the seater.”
Umm, what?

What I mean is, something in that seater die is dragging on the bullet. There’s a burr, or some crud, etc in that bullet channel. There’s no other cause for those marks. Maybe the ram is off square or the shell holder isn’t concentric or whatever, but they’re designed to be sloppy so that the cartridge can self-centre in the die. So, during that process, the bullet is dragging on something and getting scratched. The die should not be doing that, even if things are off centre.

Perhaps a full disassembly of the die and a light polish of any rough surface or sharp edge may help.

If it was me, I’d just send it all back.
 
What I mean is, something in that seater die is dragging on the bullet. There’s a burr, or some crud, etc in that bullet channel. There’s no other cause for those marks. Maybe the ram is off square or the shell holder isn’t concentric or whatever, but they’re designed to be sloppy so that the cartridge can self-centre in the die. So, during that process, the bullet is dragging on something and getting scratched. The die should not be doing that, even if things are off centre.

Perhaps a full disassembly of the die and a light polish of any rough surface or sharp edge may help.

If it was me, I’d just send it all back.
“I rotated the shell holder 90° and it went away.”
"It must be the seater."
-_-
 
Clean your seating die. Take it apart and use a good solvent spray on it - outside. Brakleen, something like that, only on steel and make sure you let it dry completely
 
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