Thread: Tight chamber and marks on projectile

Originally Posted by onlyhsh

Hi team

Lots of great feedbacks and things I can check, kinda busy during week days so it might take me a few days to go through them all. Here are a few quick responses.

1. carbon ring, not sure if this one applies, I've cleaned quite regularly and this rifle has only shot about 200 rounds. but still, how would i check for these?
2. seated out too long, don't think this one applies either, I think I tested up to 2.275 and shot well with no issues, this was seated deeper already.
3. rifling mark, this was probably confusing for a few people, I forgot to mention that I pushed these rounds into the chamber a few times to test, so some of them have repeated/multiple marks, now i see that looks a lot of rifling marks
4. Load data, 123gr ELDM, 28.5gr 8208, CCI SR primers, around 2600fps, previously worked a treat. I deliberately used once fired hornady black cases so I assume they shouldn't be too deformed? But they were fired from this chamber so I could be wrong. Btw, factory ammo fired fine but lost accuracy as well, so frustrating.
5. Sizing for neck & shoulders. I use redding FL sizing, follow the rule to get die to touch shell holder then another quarter turn, not sure what more to do, also got myself some headspace gauge kit, will test to see if shoulders are bumped back properly.
6. concentricity, I suspected this, will try to borrow some gauge and test it.

Thanks a ton team! Fingers crossed I can get this to shoot again. It's been such a good rifle and got me most of my deers.

Greetings Again,
Reading through this post I spotted that accuracy had gone sour with factory loads as well indicating an issue with the rifle as well as the loads so a check of the usual suspects, loose guard screws, scope mounts etc plus the carbon ring mentioned by others. The problem with the hard closing will remain and looking at the pictures again I believe I can see where the jacket material has been scraped by the top of the rifling. Checking the Hodgdon and Nosler load data I note that the Nosler book max of 27 grains with the 125 grain projectile is at 99% of capacity so your load of 28.5 grains is certainly compressed and well over book max for the two sources mentioned. You might want to measure some of your older loads to see if there has been any creep from the compressed charge.
Trouble shooting load problems is a character building experience.
Regards Grandpamac.