Headspace questions galore!

[alf]

I'd buy new 7mmRem brass and run it through the FL sizer creating a false shoulder.

True, and that's probably what I would do, except.......

This is for someone else, so keeping the brass with proper head stamp is a bit more important I'd think.

 

[BoydAllen]

I think that you might consider that if the barrel is original, that either an over pressure situation has caused the headspace to increase, in which case the rifle should be examined to see if the action' strength has been compromised, or the factory goofed. Another possible cause could be that someone substituted a barrel from another rifle and ignored proper headspace in favor of sight alignment. If a check of the serial number shows that the action was originally barreled in that caliber, perhaps your friend should consult with the factory about having them look at the work, with an eye toward fixing it, if it was indeed their goof. Just a Thought.... I would never tell someone that it is OK to use a rifle that is that far out of spec., even though many of us know how to work around the problem. All that would need to happen is for the rifle to end up in the hands of one of the many "die to shell holder, I want my brass to live forever" shooters, for a disaster to take place. IMO it needs to be put aside until it is fixed...correctly.

 

[wapiti25]

The barrel could be set back one turn to keep the sights in alignment and then rechamber to proper head space.

 

[fguffey]

"and I'm not sure there is really any problem. I don't have chamber gages for a 264 Win Mag, but I used a"

I do not have a 264 Win Mag head space gage, because, I do not shoot gages, and I can not do both, head space off the belt and off the shoulder of the case, in the old days what happened in front of the rim and or belt was of little concern, the purpose of the belt and the rim was to tie the rear of the case to the rear of the chamber and let the case body, shoulder and neck fill the chamber, that works today 'if' the reloader applies the leaver policy, once the case is fired leaver that way, do not full length size the case and start over.

Reloaders have bad habits, they go to the range, fire a case just to see what will happen, meaning they do not know the effect the chamber is going to have on the case when it is fired. I determine head space first then form then fire, no surprises.

If I was curious about the head space of a 264 Winchester I would use 7 Remington Mag cases or 338 Winchester Mag cases but I would prefer the 308 Norma mag case, the 308 Norma mag shoulder is forward of the 267 Winchester mag shoulder .045 thousands, this does not mean much to most but to me it allows me to put the shoulder where I want it 'if I have confidence in my press die and shell holder, and a forming die makes all methods and techniques easier. If I was using a 7mm Remington mag case, I would start with adjusting the die off the shell holder .010 thousands with the aid to the press tool the feeler gage. Adjusting the gap between the top of the shell holder and bottom of the dies prevents the process of sizing from moving the shoulder back 'by that much' and no, 'it is not bumping', bumping sounds too much like an accident, when I size/form a case and the shoulder is exactly where I want it, it is no accident. (When using a 338 Win Mag case to determine chamber length in a 7 Remington Mag or a 264 Win mag time is saved, it is not necessary to neck up a 264 Win mag to get the secondary shoulder, the 338 Winchester mag case is already necked up, and yes there is some trimming to do, remember when necking up, the neck gets shorter, when necking down, the neck gets shorter, there are some cases that shorten by as much as .035 thousands when neck up from 30/06 to 38 Whelen or 338/06.

If after forming/sizing the case will not chamber, I decrease the gap and repeat the procedure until the case will chamber, and do not forget, the gap between the die and shell holder can be used to adjust the die to the shell holder when sizing cases to head space on the shoulder instead of the belt for that particular chamber.

Failure is built into the technique when fired/fat cases are used, or cases that have been fired to form then fired an additional 5 times and neck sized, I find it impossible to full length size those cases and start over, after all they have been fired 6 times, there was a time when a disciplined reloader would fire a belted case from 4 to 5 times and then retire the case.


F. Guffey