Headspace is a NO-GO

Bob Green

I have a Model 1894 Mauser Carbine that I've had sitting in the closet for almost 40 years. Never fired. Someone sporterized the original stock back in the 50's but otherwise its all original. All the numbers match.

Since I got this bug to start collecting Mausers, I invested in a set of headspace gauges. The bolt on the M94 is closing on a NO-GO but not on the FIELD gauge.

Just wondering what a gunsmith will have to do to to get it back into tolerence? Expensive?? I really want to keep it all original. Gift from my dad when I was 14. If I ever come across an original M94 stock, I'd like to put it back like it was.

Tailgunner1954

Question, did you strip the bolt before you tried the gauges? With a stripped bolt, did the cocking handle fall to the fully closed position, or did it take a "little help"? I'll assume that you know better than to "force" a HS gauge

Anyway, to answer your question:
Remove the barrel
Check the lugs for setback/denting
Remove IIRC .090 from the breach face and tennon shoulder (IOW the amount of metal it takes to turn the barrel back 1 full turn)
Recut the chamber, to GO (minimum) to GO+.001
Re-install the barrel

About $150 for a real smith, no idea what Bubba would charge.

Bob Green

Yep, striped down. Bolt closed with zero push to get it down.

Thanks. $150 doesn't sound too bad...NO BUBBA's

jonk

Well if it were ME I would just shoot the darn thing. If it didn't close on a field gauge then it is not TOO far off. Just because a military gun exhibits slighlty excessive headspace doesn't mean that the lugs are set back, it could have been built that way. If the bolt opens stiffly, then that might be taken as a sign of lug setback.

There are also different sets of specs on headspace gauges. Modern SAAMI specs might not be the same specs the Swedes were using in 1894.

If you handload you can fireform brass and neck size only to eliminate your headspace problem. If not, if it isn't closing on a field gauge you aren't so out of spec that you'd ruin brass on one firing.

Bob Green

Thanks Jonk,
Got the EXACT same message from a gunsmith. Bolt open smooth without any stiffness.

v35

You'd kill two birds with one stone by setting the barrel back.
These chambers were cut for the original 156 grain bullet making the chamber freebored for the later 139 grain bullet.
Setting the barrel can reduce or eliminate the freebore.

Bob Green

V35...I had to do some research to understand everything in your post. This was a whole new area (freebore) that I knew nothing about. Thanks for the education.

MIKE WISKEY

I'm with Jonk on this one, if it will not close on a 'field' gage you can fire it safly. If you reload you can seat your bullets out as long as the magazine (or throat)will allow. If you just want to improve the heaspace the barrel can be faced off a few thousadths and the sights realined.

v35

Huh? To decrease freebore the barrel will have to be faced off a minimum of one pitch (.080") and the barrel screwed in increments of one turn. It will probably take setback of two threads to eliminate freebore. The chamber will then have to be recut deeper to arrive at the correct headspace.
I agree, the rifle should be safe to shoot as is, not closing on the field no-go gage.
Seating the 139 grain bullet out to the rifling will mean bringing the bullet forward on the order of 1/8". It may then be too long for the magazine.
This freeboring as a result of using a smaller, ogival bullet doesn't seem to bother others.
Weatherby freebored his magnums to obtain high velocities but I believe accuracy wasn't the best.

MIKE WISKEY

"Huh? To decrease freebore the barrel will have to be faced off a minimum of one pitch (.080") and the barrel screwed in increments of one turn. It will probably take setback of two threads to eliminate freebore. The chamber will then have to be recut deeper to arrive at the correct headspace.".......well first, these rifles don't have "freebore" they are just 'long throated' (weatherby's freebore was about 1"). This is a carbine with iron sights and a long throat woun't make any difference as far a practical accuracy goes. factory ammo will do just fine but if you reload you can seat your bullets out farther (as far as the magazine will allow) to decrease the bullet 'jump' to the rifling. The Swede's changed to a lighter (shorter) bullet but never changed the chamber spec.'s with no problems.

v35

I stand corrected on the procedure to reduce headspace. It was assumed incorrectly there was an extractor cut in the chamber end of the barrel.
However, freebore is freebore. Long throating is freeboring. It promotes throat erosion as well as inaccuracy.
This may be academic if the rifle isn't shot much or best accuracy isn't
an issue.