At the chamber, what is the minimum amount the shell should stick out of the barrel?

[bsekf]

After reading this thread and thinking a little (dangerous)! Is it necessary for the chamber end of the barrel to be perfectly square with the chamber. There is about 1/8 inch clearance between the bolt head and the end of the barrel, Savage bolt head floats, so is a perfectly square barrel face necessary?

I have a barrel that has the chamber cut a little deep and when I headspace I am hitting the end of the barrel. I see no reason I couldn't just use a file to remove a few thous.

Redneck engineering and gunsmithing! Setting a barrel back with offset grinder and file!

[tobnpr]

You can't "clean up" an eccentric chamber by just running another reamer in.
Running another reamer into it- whether by hand, or under power- isn't going to change it. The reamer will follow the existing hole.

That problem can only be resolved on a lathe by indicating the bore with a range rod, and using a boring bar to true the chamber to the bore/lathe axis, setting back and re-cutting the chamber.

[Robinhood]

After reading this thread and thinking a little (dangerous)! Is it necessary for the chamber end of the barrel to be perfectly square with the chamber. There is about 1/8 inch clearance between the bolt head and the end of the barrel, Savage bolt head floats, so is a perfectly square barrel face necessary?

I have a barrel that has the chamber cut a little deep and when I headspace I am hitting the end of the barrel. I see no reason I couldn't just use a file to remove a few thous.

Redneck engineering and gunsmithing! Setting a barrel back with offset grinder and file!

There is only .005"-.015" between the bolt head and the barrel breech face.

Use a Gage to measure the protrusion. (the problem could be your sizing process)

Like Fred said, measure the depth of the bolt face and measure protrusion. The protrusion number must be greater than .005" than the bolt face depth.

[mnbogboy2]

After reading this thread and thinking a little (dangerous)! Is it necessary for the chamber end of the barrel to be perfectly square with the chamber. There is about 1/8 inch clearance between the bolt head and the end of the barrel, Savage bolt head floats, so is a perfectly square barrel face necessary?

I have a barrel that has the chamber cut a little deep and when I headspace I am hitting the end of the barrel. I see no reason I couldn't just use a file to remove a few thous.

Redneck engineering and gunsmithing! Setting a barrel back with offset grinder and file!

This will work with no problems providing the original chamber isn't "egged" as tobnpr mentioned. I've shortened the breech with a hacksaw on numerous occasions and squared it up with a big bastard. Any craftsman can get within a thousandth or two and that will pose no problem. Just make sure the go-gauge protrusion matches the bolt head recess + your desired bolt head to breech face clearance. It usually falls in that .125 to .130 number. Some aftermarket heads like PTG may require a little bit more.
Make sure the reamer pilot matches the bore just ahead of the throat. Do all the hand reaming vertically with the barrel mounted below your work station. I have a barrel vise mounted specially for hand reaming and stand above it on a stool to provide constant equal down force on the reamer. The reamer will follow the "old" hole, as long as you don't induce side pressure. I do not recommend trying a full chamber with this method. Withdraw the reamer every .010 - .025 and clean it and the chamber & barrel. Re-lube each flutter with cutting oil each pass. Use a reamer stop for the last passes. I've only done this 10 or 12 times to create Ackleys , wildcats or simple cartridge swapping. Not for complete chambering.
Yes it works fine if you have the time. There is a learning curve.

[Robinhood]

This will work with no problems providing the original chamber isn't "egged" as tobnpr mentioned. I've shortened the breech with a hacksaw on numerous occasions and squared it up with a big bastard. Any craftsman can get within a thousandth or two and that will pose no problem. Just make sure the go-gauge protrusion matches the bolt head recess + your desired bolt head to breech face clearance. It usually falls in that .125 to .130 number. Some aftermarket heads like PTG may require a little bit more.
Make sure the reamer pilot matches the bore just ahead of the throat. Do all the hand reaming vertically with the barrel mounted below your work station. I have a barrel vise mounted specially for hand reaming and stand above it on a stool to provide constant equal down force on the reamer. The reamer will follow the "old" hole, as long as you don't induce side pressure. I do not recommend trying a full chamber with this method. Withdraw the reamer every .010 - .025 and clean it and the chamber & barrel. Re-lube each flutter with cutting oil each pass. Use a reamer stop for the last passes. I've only done this 10 or 12 times to create Ackleys , wildcats or simple cartridge swapping. Not for complete chambering.
Yes it works fine if you have the time. There is a learning curve.

And in other news..... LOL

[mnbogboy2]

Here is an example of a "hacksaw" rechamber quicky. Was a .260 Rem, hacksawed .250 off breech, filed square, ran 6.5 creedmoor reamer in .075 deeper than creed depth. Used 260 brass in creedmoor die to bump length...trim to 2.003. 2-1/2 grains more capacity than CM and shoots ok. Barrel did have over 1000 rounds so no break in was required.

Edit: this was 5 shots at only 100 yards with Berger 130 vlds pushed with h4350.
Also .010 off with no other load developement. Velocity was 2984 ave over 5 with sd 9.1 over mag speed.

[Robinhood]

Can't argue with results. There was a big name gsmith over in Webster Texas. He did a hand reamer job for a friend. Don't know why he didn't set it up in the lathe, it was a long fluted 308 barrel with 10 rds being reamed to a win mag. It came out like a 5 sided cam. Worst thing i have ever seen.

[mnbogboy2]

Can't argue with results. There was a big name gsmith over in Webster Texas. He did a hand reamer job for a friend. Don't know why he didn't set it up in the lathe, it was a long fluted 308 barrel with 10 rds being reamed to a win mag. It came out like a 5 sided cam. Worst thing i have ever seen.

Think that was somewhere in the middle of that learning curve....lol....a 308 to winmag is a "stretch" to begin with, a lot of material coming out of that one. My bet is he tried it horizontally and was "pushing his guts out" trying to "speed" up the cut.....oh well...his time saver proved the theory that haste makes waste....
Btw: the first A.I. I did many years ago was done "horizontally" and it wallowed out somewhat. Cases didn't stick and that old savage barrel shot fairly decent (25-06 to 257 Bob Ackley) but cases were "stiff" on resizing because of a nominally larger base. Went verticle after that in several different calibers and never had that problem again.
Now in the day of Teslong you can choose your "Guinea pig" barrel and examine the chamber ahead of time.....if it's eccentric to the bore other result will not be either. As tobnpr mentioned it must go into a lathe and a boring bar will straighten the hole before chambering....then is it worth it?