12FV: copper shavings, tight bolt, marks on brass

[Muddly]

Just a guess, but I think that scratch is happening during extraction/ ejection. My 110E 243 gets scratches when the case mouth clears the chamber and angles up in the bolt raceway in the right receiver ring. Check there for a burr.

[quigley257]

I'm still baffled by it, but I couldn't reproduce it the other night. I took a case that had no scratch and cycled it through 10 times. No scratch. Weird. Unless its happening when it's hot/expanded after a shot...but I have a factory unfired round I have never fired and it has the scratches from cycling.

I realize now that the tight bolt was from not sizing the cases down a little more. I'm new to reloading 6.5, and it's obvious a little extra turn on the sizing die was needed.

I did clean the chamber really well Sunday night. I used a .38 nylon brush with some never dull in a drill bit. Maybe that was the cure? Again, it's a weird one. Guess it's nothing to worry about for the moment since I can't reproduce it. I'll keep an eye on it next time I hit the range.

Concerning the case that you used for the last "test", is it one with a bullet seated in it or just a new case? Keep in mind that a new, unloaded case will have a neck diameter that is several thousandths smaller than a loaded round. You may not replicate the scratch on the neck without a bullet seated in the neck to expand the case to its full diameter. The scratch on the neck certainly looks like a burr on the shoulder/neck transition area to me. You could get a definitive answer to this by first chambering a new, empty case, then seat a bullet into it and rechamber it and see if the scratch appears. If you know someone with a finish reamer they could easily just touch the chamber up by hand if there is a burr in it. Good luck!

[Stumpkiller]

A fired empty case will have an even larger neck.

But your .38 brush & pad may have removed the burr. :thumb: