head space

[Leeper]

Actually, I meant whatever it takes! Mostly, I adjust headspace by fitting new barrels or setting barrels back. Lee Enfields stretch. The heavier the load, the more they stretch. With mild loads, cases will last well. With maximum loads, they will not.
My #4 (in 30/40 Krag) will separate cases in about a half dozen firings if I load 180s to 2500 fps. The chamber is tight and the headspace is minimum.
On a No1 MkIII, I set the barrel back to where I actually had to face the brass (thin the rim)to get it to fit. 180's loaded to 2450 fps with 4350 caused brass to fail on the fourth loading. Neck sized only. Backing off to the 2300 fps mark doubled case life. This was done just to experiment, by the way.
I like Lee Enfields. The Lee Enfield was my first rifle and I still hunt with one a lot. It was the rifle I learned reloading with but it's not a reloader's dream! It's hard on brass and sensitive to load changes. Stay within it's limitations though and it works pretty well. Regards, Bill.

 

[fingers284]

Define it however you like but Mooncoon is right the critical measurement is between the cartridge base when fully chambered & bolt the face. Guntech's method of measurement using the protruding primmer is the best way to measure how much the gun is out of spec.. All a nogo gage tells you is that a gun is in or out of spec and not how much if it is out. Primer measurement tells both. I use a fired primer started in an unprimed case & close the bolt on it

 

[mooncoon]

. Guntech's method of measurement using the protruding primmer is the best way to measure how much the gun is out of spec..

I have actually made a guage by turning a shell out of steel with a screw in the center where the primer would be and a locking screw from the front to keep the protrustion in place. For rimless shells you can make them jointed in the middle of the shell and again with a locking screw so that overall length does not change as the bolt rotates. You could accomplish much the same thing with a bit of thought by using an adjustable screw in the primer area of a empty factory shell.
What I am not sure about is just how much headspace the extractor will allow; in other words the extractor holds the shell somewhat tight to the face of the bolt and so you may be measuring the amount of space between the bolt face and the backside of the extractor. That is not a problem with sensible rifles such as falling blocks :>) :>)

cheers mooncoon

 

[got to go]

. Primer measurement tells both. I use a fired primer started in an unprimed case & close the bolt on it

That seems like the simplest way to do it Jack