A buddy had a 500 jeff built by a well known shop.
To cut a long story short, tight chambering and a headpace problem was diagnosed by another well known custom gunsmith.
The tight chamber cure proposal was to polish the chamber out by about 1/thou" ?!?
The excessive headspace problem should be cured, but how?

I'm trying to figure out how a chamber gets cut to long AND too tight at the same time. Because of the taper in a chamber, it you cut it too deep (excess headspace) it will be larger in diameter. Was the original reamer faulty?

500nitro,

Does your friend reload? How much excess headspace is he dealing with? Is he trying to avoid altering the barrel?

If he reloads it should be easy to use a tapered expander (probably needs to be at least 20 thousandths larger than bullet diameter, and a little more would not hurt) to increase the neck diameter of his brass. Then it is a simple matter of backing the sizing die off far enough to create a secondary shoulder to provide a crush fit in the chamber for the initial firing. After the initial firing it is just a matter of setting the sizing die properly for future reloads so that the shoulder does not get set back. It is also pretty easy to use a lathe to reduce the base diameter of the brass a few thou if he wants to avoid polishing the chamber (I have a couple of rifles that I have to do this for as well). I am sure that this is all information that you had already thought about, but it is the only way short of altering the rifle that is practical.

If he does not reload it is probably going to involve setting the barrel back one or two threads, and cleaning up the chamber with a reamer. If this is the case it would be a good idea to use a different reamer with the proper base diameter.

Jim

There are at least two different 500J chamber reamer "Standards" in existance, and the 500 AHR is a third one to throw in the pot that is different. And 500J brass is known to be different in dimensions among makers.

Solution: Obtain an accurate reamer drawing, from the reamer maker. Compare the dimensions to the brass and a loaded cartridge.

You may have a mis match between reamer and the brass.

What is the "tight chamber" and "headspace" problem? Is the chamber too long, or too short for the brass? Is the chamber diameter too small for the brass?

John,
it appears that the chamber is a tad narrow and is too long.
The person who is doing the rectification work has undertaken to polish the chamber out to size and then weld up the boltface and cut a new face to overcome the headspace problem.
He is the local H&H representative/agent so he ought to be the resident expert
Right?

FORGET THAT!
I'd take J.R.'s advice, and if it is a mismatch, find some brass for my gun. If it isn't a mismatch, and if this was a reputable shop I'd look into them replacing the barrel with one chambered in 500 Jeffery!
That's just too much work to be dealing with, and I'd always be wondering how the boltface was doing today.
Also, not sure how they plan on polishing the chamber, nor how tight it is to start, but if it were mine, I'd cast it and see for myself that it had plenty of tolerance for the work it'll be doing.
As for H&H rep's being gunsmith experts, DON"T BET YOUR LIFE ON IT!

500 , anyone who told me he want to weld up the bolt face and cut a new one to solve a headspace problem , it's an incompetent blacksmith , even if he is H&H representative or a horseshoe fitter .

Daniel

500nitro, that's certainly a novel way of handling the problem. The way I, and everyone else I've ever talked to, handle a problem like this is to set the barrel back one or more turns to correct the excess headspace, then recut the chamber with a proper reamer. The method you described seems mid-evil at best. Sort of like leechs and bloodletting. I could go on and on about what's wrong with setting headspace by welding on the boltface, or enlarging chamber diameter with sandpaper-on-a-stick, but I won't.

If your friend is bound and determined to go this route, I wish him and his rifle all the best.

Guys,
I threw this thread in as a red herring to see the response. It was mild compared to mine when my buddy told me what was happening.
It is sad to see who and what wanders around and hangs up a "gunsmith" shingle sometimes, and in this instance (H&H AGENT) charges accordingly
M Pursell, I agree, the only way to have addressed this problem would be to set the barrel back a turn and work from there. And he should have done this with the shop that built the darn thing in the first place.

500nitro, you had me going. I never know exactly how to respond to comments of "blacksmithing" like you described. In person, I usually stutter something like "uh, well?, OK". On one hand, I hate to see somebody jump or get pushed off the deep end. On the other hand, I don't want to anger folks by insulting their favorite blacksm.... gunsmith. A classic dilemma.

I do agree with you that the best thing would be to take it back to the shop that built it. Everybody makes mistakes. Occasionally they get out the door. Most good people, in any type of business, appreciate customers that give them a chance to make it right.

Mark