New bullet, new prob ...

[Old Jim]

problems. It seams to group ok at 3oo but with the bullet touching the leade, there is a tiny ring of lead on the mouth of most the fired cases. What gives here? I never had this before. Cases are 2.095+ in the 45/70 Shiloh.

Will seating the bullet deeper get rid of this?

Jim

[Don McDowell]

Are you crimping those?

[Old Jim]

No crimping, just FL sizing of Starline cases. There is a very slight flare on each case.

Jim

[drcook]

try annealing the cases and see if that helps. usually Starline cases are pretty hard as recieved.

also what alloy are you shooting, and are you putting a wad in between the powder and the bullet ?

[bobw]

From what you say it sounds like your cases are a little short and the drive band of the bullet is bumping up into the gap from the end of the case to the end of the chamber. Maybe try a harder alloy. You take about 5 of your cases and stretch them a little by not lubing the inside of the necks when you expand and bell them. Mark the back end of them with a Magic marker and see if you get the lead rings with the longer cases. bobw

[Old Jim]

Well, after culling all cases under 2.1, I shot a couple of 2" groups this morning @ 200 meters, with only a very slight lube ring at the end of the cases, no lead ring. Currently, thats what its going to get LOL.

Jim

[Kurt]

Jim what your seeing is nothing uncommon with a chamber that has a 45 degree end.
I can find a ring paper or lead depending if I use a PP or GG bullet.
That is the biggest cause of lead in the bore. It starts at the chamber end and shot after shot it gets smeared forward.
This will even happen using a PP bullet with very thin paper.
If you have a good bore scope you can see that ring after shooting in a clean barrel if the gases didn't blow it out.
If your case is short and a lube groove ahead of the case mouth will stop a lot of that lead ring problem, but a PP bullet you will get the ring. It will be there if you look for it.
Below are some rings I found from 7 out of 10 shots fired with brass .006" short of the chamber end. The tighter the case fits the smaller in thickness the rings will be.

Kurt

[Old Jim]

Thanks Kurt,

After doin' away with the short cases, the lead rings disappeared. Now I have a very thin lube ring on each case-mouth. That's something I can live with. I got to get busy loadin' for the Quigley.

Jim

[Don McDowell]

Maybe you ought call Baco and have Dave bring one of these down to Forsyth for you.http://www.buffaloarms.com/case_stretching_tools_pr-3894.aspx

[Kurt]

See you at the Q Jim.
I will be in a Raptor 5th wheel pulled by a maroon GMC.

Kurt