headspace

[ckoellerdvm]

I had taken a mauser that i got to a gun smith and he checked head space but could not do the same for a carano i have. i rented the gauges for both guns. the mauser would not close on the go gauge until the extractor was removed then closed easily and smoothly. the carcano does not quite close on the go with the extractor and ejector on. i have looked and it seems that theses should not be pulled off the bolt unless absolutely necessary. Any thoughts on this. really would like a true test before getting ammo.

[red dog]

I was taught that it is best to remove the extractor and ejector to acquire a good gauge fit. the instructions that have come with my gauge sets also say to do this. when in doubt go with the manufacturers recommendations. jmo

[ckoellerdvm]

thanks reddog. i think it will make a difference as that is what manufacturer of gauge says but worried over so many saying not to remove them from this weapon. anyone ever removed the extractor and ejector from a corcoran 6.5 mm

[aubie515]

I own go/no go gages and I've never heard of having to remove anything from the bolt for it to work.

You should be using the gages as if it was ammo to check head spacing. Simply slide the gage into the chamber and try to close the bolt.

[red dog]

i suggest checking out forster,s sight. they have specific info on the usage of their guages as well as general info on the different types and purpose of them. just saying.

[ckoellerdvm]

with the carcano you can't put a round in the chamber have to use the clip or place under the extractor.

[762xIan]

I own go/no go gages and I've never heard of having to remove anything from the bolt for it to work.

Depends on the rifle type if you really should or not.

It is a recommended practice in most of the gunsmithing books for bolts that have an internal spring loaded ejector (the spring tension can be pretty strong) such as on bolts like the Garand and Rem 700...etc. The other issue is with bolt actions that use controlled feed, on many the extractor will not close over a chambered round, they are designed to feed off the magazine.

A lot of Mausers extractors (and mauser based actions) won't close or will but with a lot more force than feeding from the magazine. Not something you want to do when checking headspace. A Springfield 03 will because it was designed with a magazine cut off to feed single rounds. If you have one of each you can see there is more of a "bevel" on the 03 extractor than on a Mauser. It will snap right over a chambered round.

If you force it, you can chew up the rim on your gauge.

That said, I myself have only taken bolts apart when rebarreling a rifle with a new barrel. For a simple headspace check, I am NOT dissassembling anything either, other than cleaning the chamber and bolt face.

I have had no problem manually "feeding" the headspace gauge onto the bolt. You just make sure the rim is under the extractor like the bolt is feeding a normal round and it works no problem.

[justashooter]

with the carcano you can't put a round in the chamber have to use the clip or place under the extractor.

the carcano is a controlled feed action and the extractor will not override the rim of a cartridge that is just dropped into the chamber. this is an issue with some headspace gauges, and not with others.

[Noah_Zark]

When I check headspace I don't disassemble bolts.

For rifles with bolts with plunger ejectors I take a die grinder or Dremel and grind a clearance hole in the base of the gauge to clear the ejector plunger. My USGI gauges for the M1 Rifle already have notches for this purpose so that bolts don't require disassembly.

I simply clip the gauge rim under the extractor, hold it in place, and ease the bolt forward until the gauge starts into the chamber. Then I continue to ease it forward until the bolt stops, then rotate the bolt handle down VERY gently until it stops. Use no force.

I did a comparison on several rifles once where I used the above procedure, then repeated the headspace check after bolt disassembly. There was no difference in where the bolt handle came to rest as the gauge contacted the taper in the chamber.

Noah

[Bama Man]

I know on a Mauser the controlled feed requires you to clip the guage onto the face of the bolt before you try to force it into the chamber. It will not close if you don't do this, as the extractor will not go over the guage with the bolt almost closed. Only a "push feed" bolt will.
I don't know if the Carcano is controlled feed or not, but if it is, it should act the same.
Simply remove the bolt, clip in the guage under the extractor and carefully replace the bolt with the guage in place. It may take a few trys to accomplish this, but it will work.
The extractor should hold the guage in place.