Why won’t my bolt close?

[LazzInc]

I probably should not butt in here, but why not screw the full-length resize die down just far enough to get the brass to chamber, but not so far as to drive the shoulder back ? ,,,,

 

[260 rem]

Try a fired case that you have not resized yet dose it still happen if so the chamber could be off square with the bore or chamber is oval

 

[Stgraves260]

Im shooting a Bergara B14 HMR in the dreaded 6.5 C M. Load is 143 ELDx, 41.5 gr. H4350 CCI BR2 primers, Hornady cases. Seated .015 off the lands. Here's the problem if I neck size a fire formed case the bolt will not close on about half of the rounds. I neck size everything except 223 and have never ran into this. Any ideas, suggestions. Don't really want to FL size if I can keep from it. Thanks!

That sounds like a head spacing issue. That's happened to me before on a new gun. Luck of the draw I guess. You mite be able to fix it by readjusting your full length seating die. On my Redding T7 reloading press I run the ram all the way up then I set my full length die down till it touches then back off 1/4 turn. See if that helps. If not just run the die down 1/8 turn until all your casings fit in your chamber. I had to do this for my pop.

 

[nkyshooter]

rick253 ...

Wondering if you've had this issue since day/shot 1 on this rifle? ...

I have been (and still am) a neck sizer only (until a VERY slight VERY occasional bump is required) and I ran into this 'same' issue with a new 260 Ackley barrel a few years back. Fired cases wouldn't rechamber consistently unless I FL sized.

The issue for me turned out to be a flaw in the chamber ... it was ever so slightly "egg shaped" and so there was a bit of a bulge that was forming on one side of the cases upon firing ... if the case was rechambered maintaining the same 12 o'clock position, no worries ... if not, I could not close the bolt on it.

In my case, it required sending the barrel back to the maker and he sent me a different barrel - problem vanished.


BTW - regarding NS vs FL sizing - if you are running PRS competitions, I recommend FL sizing ... if you are hunting in environments with dirt and/or inclement weather (beyond just rain) then I recommend FL sizing ... If you tend to shoot targets in controlled situations and ESPECIALLY if you are on the hotter end of the load chart, neck only with occasional shoulder bump will be more accurate, extend brass life (sometimes very significantly), and it will reduce thrust against the face of your bolt experienced upon firing (although potentially higher during chambering, this is nothing compared to when firing and a few thousands of 'momentum' from the 'slop' slams into the bolt face)

 

[TwoMore]

It may have been already discussed so I apologize before hand, but if you have a chamber that is on the loose side and you neck size you could be running into the problem of the die still narrowing the shoulder body area on the fired case and if it is, the shoulder will be pushed forward and your headspace will be to long on the case so you will have to set that die up to bump back the shoulder, good luck I hope you get it lined up

 

[FEENIX]

Dead horse but still going lol

... it is going to be at least a 20-pager.

 

[TwoMore]

... it is going to be at least a 20-pager.

Ithat horse was slaughtered last week , I think its starting to turn

 

[FEENIX]

Ithat horse was slaughtered last week , I think its starting to turn

Agreed, but that never stopped the beating momentum before. LL!

 

[PApa Black]

Why not FL size? I FL size every time, bumping shoulders back .0015-.002". Accuracy is phenomenal with a good load.

By the looks of your charge weight, you are running a pretty hot load. My guess is shoulder and body need to be resized and bumped back. No reason not to, and apparently, every reason you need to if the bolt won't close on a neck sized and loaded round.

I agree with Lance 100%

 

[rick523]

Okay guys thanks for all the response, the consensus is to FL size with a .002 shoulder bump. That is exactly what I was doing when I did FL. I would then NS and would still have a closing issue with 20-30%of the rounds. For those of you that said my load was to hot. There are absolutely no pressure signs you can open bolt with one finger, no cratered or flattened primers, no extractor marks. What I couldn't understand was why the bolt opened flawlessly but wouldn't close. I'm leaning toward an out of round chamber. Since all my brass has been resized I will shoot this weekend and then try to re chamber fired brass if it won't chamber next stop will be to my smith to have him check chamber. To be continued!

 

[Randy Tidwell]

Did you measure the shoulder/body diameter before and after sizing.

I have seen this area swell a number of times when neck sizing if the die is screwed in to far.

Another way to check, unscrew the neck die 1/2-3/4 turns, neck size a fired case and see if it will chamber.

IMHO if you had a chamber that is out of round enough to cause the problem you are having, you would be having allot of other issues besides not chambering.

 

[MNbogboy]

Agreeing with Randy Tidwell. The neck sizing die should be set so it is not sizing all the way to the neck shoulder junction.

 

[rick523]

I agree with you both! That is the way I set them up. Been doing it that way for quite some time. Bye the way never got to shoot this past weekend. Storms both days, not complaining we need the rain.

 

[MNbogboy]

I'm a long time neck sizer myself in many calibers, generally with the Lee collet neck sizing dies. I'm curious if you guys feel that an effective and consistent shoulder bump can be achieved using my existing traditional Lee, RCBS, or Hornady FL dies? Sure, I could buy new "bump dies" all around, but would prefer not to. Thoughts?

Problem is unless they are bushing or collet dies they undersize the neck more than they have to.