chambering problems

[foxshot]

Just got off the phone with my mate, he has loaded himself 50 rounds up,some of them are very hard to chamber but others are ok,what could be the problem,all cases have been trimmed so i dont think that is the problem

[col48]

Just got off the phone with my mate, he has loaded himself 50 rounds up,some of them are very hard to chamber but others are ok,what could be the problem,all cases have been trimmed so i dont think that is the problem

 

 

not entirely sure, but it sounds like he needs to bump his shoulders back.

basically your brass flows forward every time you fire your cases, (most brass migration is on your first firing)

this pushes the shoulder forward and results in - head space, making the bolt hard to close.

depending on which type of dies he uses he might be able to bump them back with his dies he all ready has.

if not a bumping die can be brought, or a full length sizer

all so he could have sat his bullets to long and he is having to seat them as he closes his bolt, this could be making the bolt hard to close,

he could have not trimmed his cases to the right length,

but my guess would be the first one, is he just neck sizing????

 

ATB

Colin

[Ronin]

+1 on what Colin has said

 

The cases need shoulder bumping back with body dies.

[17 Rem]

Col's right.

It could be as simple as incorrectly adjusted dies resulting in insufficient resizing.

[Andrew]

Too little information. Was the brass all from the same lot? fired in his rifle? Was he full length resizing? ~Andrew

[eldon]

Hi,

I had a similar issue with a remy 700 in 308 and lee dies.

I struggled to find a difference with a micrometer so I turned some dummy chambers up. With these I could measure to the headspace point on the case taper. Lo and behold the cases were't sizing correctly even though the dies were set as specified by lee.

If I was you as I did mark up a bad fitting round and a good fitting round with marker pen. Strip them and turn your die in 1/8th of a turn further (mine needed about 1/4 turn) and retry the case in the chamber.

Without a tool of some sort you will struggle to measure it but you will certainly notice it? numbers don't matter as you can use the gun chamber as a go no-go sort of set up.

 

On the bipod a bad fitting unfired round was lifting the rear of the gun off the floor and required 2 hands for extraction, a good fitting round didn't and you could lift the bolt easily with a little finger. The difference in headspace measurement was only 3 thou

 

Hope this helps

Paul

[Guest northernchris]

FoxShot you could just surface grind some material from the upper face of the shell holder to "move" the shoulder back,would save getting body dies.

[Guest rogern]

It may sound obvious but have you checked how clean your dies are.

As they set shoulders/necks by thous it does not take much crap (old lube etc) to throw your resizing out.

 

I strip and clean my dies with wd40 every now and again and there is always crud.

 

Just a thought.

[Redfox]

Grinding back the shell holder shouldnt be necessary as most dies will size back to SAMMI length less several thousandths of an inch. You should be able to push the shoulder back 2-3 thou easily which is enough clearance for easy chambering. The most likely cause is mixing fired/unfired cases as has been pointed out brass flow and shape change is mostly on the first firing and case length trimming is a must then.

The latest thinking on accuracy with std components and rifles is to full length re size, not only could they not see any accuracy gains in neck sizing but due to case variations and alignment issues with neck sizing the fl cases showed better accuracy.

I must say I agree with that too, it is very easy to set the dies up to give 2 thou push back on the shoulder and the case and neck are straight again in alignment, giving excellent accuracy. to benefit from neck sizing you need to have a known size custom chamber, case prep including neck turning and segregation of cases by size/ weight and a comp neck sizing die. Not necessary for varminting and pleasure shooting and likely tp put your mate of reloading for good!.

Get a Stoney point ( now Hornady) comparator gauge and the case length busings as well as a modded case for bullet clearance measuring and you can easily set up to give the minimum shoulder push back and bullet clearance in a half hour session once set up he shouldnt need to touch the dies again.

Redfox

[foxshot]

Too little information. Was the brass all from the same lot? fired in his rifle? Was he full length resizing? ~Andrew

all the brass was once fired lapua match, but it was fired in my old remi in 223, the die has now been backed off a 1/4 turn and he can now chamber the rounds, he is using lee dies,i set it up the same way as my redding comp dies and have had no problem at all granted the bolt is tight but these are fireforming loads i am using,anyhow thanx for all the advice lads

[Guest northernchris]

Foxshot

 

 

You say "backed off" ???? ie screwed the die out a 1/4? and they chamber now?

[foxshot]

screwed the die body further out from the press

[eldon]

Screwed it out.....

As my post I was meaning screwing the die in i.e. shorter distance.

I think me and northernchris are the same on this, how is this working then?

Paul