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.

This thread has been interesting.

I have a new rifle and was gifted about 50 once fired cases, I ran these through my full length resizing die a couple of weeks ago. So today I decided to check they all chamber in the new rifle, I had about a dozen that would let the bolt close.

I ran these through the die again a couple of times and that left me with 5 that won't chamber enough to close the bolt so have put them aside. I can see nor measure any difference between those that will and those that won't chamber.

Sometimes things just won't work.

Another easy thing to check is the finished neck diameter. As has been mentioned these are seriously snotty loads and you might be getting a form of neck thickening (an example of which are called "donuts"). Measure a loaded round and a fired one and let us know the results.

Originally Posted by Happy Jack

This thread has been interesting.

I have a new rifle and was gifted about 50 once fired cases, I ran these through my full length resizing die a couple of weeks ago. So today I decided to check they all chamber in the new rifle, I had about a dozen that would let the bolt close.

I ran these through the die again a couple of times and that left me with 5 that won't chamber enough to close the bolt so have put them aside. I can see nor measure any difference between those that will and those that won't chamber.

Sometimes things just won't work.

Had that with .308 before..s&b brass was terribly hard. My BLR seemed to have tightish chamber and dies on generous size...ended up pushing cases through an old Lyman 30/06 die with guts removed that seemed to work sides a bit more and half of them fitted after that treatment. Some still no good in BLR but fine in zastava bolt with its stronger camming action.

What is your rifle.
I have a howa mini with the exact same load as you however my coal is 2.280 and I'm not hitting the lands.
Could check the ogive measurement of you have a comparator but without a base measurement may not tell you much. Might have to set up a dummy round to check where the lands actually are. Easy way to rule that out for sure

stop looking at your rounds
again stop looking at the rounds
just incase you missed it first two times ITS NOT YOUR ROUNDS
you tried factory rounds and they shot like shit too did you not???? so its NOT THE ROUNDS...had they been good...yip look at yours,but they didnt so not your rounds... if you have some older rounds,even one or two..try them and chances are will see same issue.
Which leaves??? the rifle....or possible scope...but the pointers towards a carbon ring would be first place to start

Autosol on a patch wrapped around a worn brush back and forth at the chamber end will get the carbon ring gone. Ideally you check it with a bore scope/endoscope, cheap as chips off the internet, $50 from pbtech or there are some on trade me for under $20 that plug into your phone or laptop.

Jaco has made a good observation, your brass isn't being sized enough. In your picture there is a line around the base of the neck that hasn't been sized, along with everything south of that. Not all shell holders are created equally so the rule of touching and then a quarter turn needs to be proven before assuming it's enough.

Micky also raises a good point that needs investigating.

I agree with @Plinky and was going to say the same thing. There is "cleaning" and there is "scrubbing" with, I use JB BORE CLEANING paste. And just keep scrubbing it with bronze or nylon brushes until cleaning patch go through smoothly and come out clean.

Are you cleaning the fired cases in a tumbler before you start the reloading process?

Nobody has asked or mentioned case trim length. After full length resizing are you checking the case length with calipers? Then trimming to length, deburring and chamfering. Somebody else said they suspected deformation on seating projectile, chamfering can mitigate that.

Last suggestion, are you cleaning the completed cartridge to remove excess lubrication and any dirt the case might have picked up?

Some people say cleanliness is next to Godliness, but I reckon cleanliness is next to accuracy!

If your willing to sent me cases I can measure and give feedback?

Im gonna need: 2 fired in your rifle, not resized.

2 or 3 that was resized and fits into your chamber.

3 thaf has been resized but does not fit or has a tight bolt.

3 with projectile seated that does not want to fit or has a tight bolt?

Sizing die and your shell holder - So I can fix the issue should the die not be able to push the shoulder back far enough.

How will that sort the "factory loads fired fine but lost accuracy as well" thing?

Originally Posted by Micky Duck

How will that sort the "factory loads fired fine but lost accuracy as well" thing?

By eliminating a possible answer, or part of the answer - it may be a combination of things.

"When all other possibilities have been eliminated, that which remains must be the answer" - Sherlock Holmes, imaginary sleuth.

Ok.......... So changing the reload will make the factory stuff shoot good again..... Ok....

Another question for you. Have you taken the action and stock apart?
Have you now got the wrong screw in the wrong hole.... some are different lengths, not by much but enough to give you grief.

Originally Posted by johnd

Another question for you. Have you taken the action and stock apart?
Have you now got the wrong screw in the wrong hole.... some are different lengths, not by much but enough to give you grief.

Yep checked that, definitely nothing wrong there. Also checked all screws and scope, eliminated those variables.

Quick update

At first felt hella frustrated but thanks to the support from the team I'm feeling more curious and excited to jump into this rabbit hole. like grandpamac said, character building indeed
1. endoscope on the way, cheapie Trademe version, potentially go for Teslong later.
2. JB bore paste on the way, if carbon ring is the issue I read this works.
3. will holla at friend to check concentricity.
4. will use head space gauge to for the first time, ordered a different shell holder in case shoulders are not getting bumped back enough.

Wish me luck. Worse case scenario I'll get a new action next year (license renew and have to get on rego), then make a new post asking what project (rebarrel/rechamber?) I can do