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On a 30-40 Krag is it necessary to strip the bolt on headspacing?.. or just make sure the extractor is over the rim?
I will be using Forster H/S gauges.
Thx
 

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Have no idea how headspace gauges work. Thought they went into chamber and bolt closed?
 

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On a bolt-action rifle, they say it's best to remove the firing pin assembly and the extractor. Then insert the gauge, try to gently close the bolt. DON'T FORCE IT!!!!

Correctly headspaced rifle will close easily on the "GO" gauge. You should feel no resistance. It will not close on the "FIELD" gauge.

If it closes on the "NO-GO" but not on the "FIELD"; it can still be used but accuracy will suffer.

If it closes on the "FIELD" guage you have what's known as a "Club". DON'T FIRE THE WEAPON!!!!! YOU HAVE TOO MUCH HEADSPACE!!!

HEADSPACE- The distance between the face of the breech and the base of the cartridge, with the bolt closed.




:sniper:
 

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Isn't it the face of the closed bolt to the "datum line"?
Datum line being differnt on rimmed, belted and rimless, beltless cartridges. :confused:
 

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On a rifle, or pistol, chambered for a rimmed, or semi-rimmed, cartridge (the 30-40 is rimmed) the head space is from the bolt face to the receiver face.
On a Belted case the headspace is from the boltface to the bottom of the belt recess.
Auto pistols headspace from the boltface to the end of the chamber.
Rimless bottle neck cartridges headspace to a datum point on the shoulder.

The reason for removing bolt parts is to eliminate as many sources of drag as possable, as checking headspace is a "feel" thing.

Other trivia
Rimmed and belted cases can be checked by using a F/L sized case and some tape (or a ring of thin solder) between the casehead and boltface. Verify what the dim is supposed to be, measure the rim (belt), add tape until you feel resistance to closing, and measure again (with the solder just crush it with the bolt and add the crushed dim to the rim thickness)
Belted cases often have there shoulders set way back when sized, which leads to their noted short case life (just touching the shoulder when sizing will extend their case life greatly)
 
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