New old stock bolt

[Merc]

I recently bought a NOS Winchester bolt for my M1917 rifle. Other than checking headspace with a headspace field gauge, is there anything else that needs to be done before I can start using the new bolt?

[lyman]

besides putting it together (striker etc)

if it passes headspace, and the safety etc work fine, you should be good to go,

I don't think you need to worry about fitting the lugs on the 1917's

[fguffey]

I recently bought a NOS Winchester bolt for my M1917 rifle. Other than checking headspace with a headspace field gauge, is there anything else that needs to be done before I can start using the new bolt?

As you can see I am the only member that believes you left out all of the information necessary to help you. "headspace field gauge"; the headspace field gauge gage will not allow the bolt to close. I have a M1917 that has a chamber that is .016" longer than a minimum length/full length sized, over the counter new factory round when measured from the shoulder to the case head. That is .011" longer than a go-gage length chamber.

So I ask; did the bolt close on the field reject length gage? M1917 rifles with long chambers are not rare; how they got that way is an interesting story.

F. Guffey

[Merc]

Thanks for your help. Full story: I bought the NOS Winchester bolt to replace a slightly worn Eddystone bolt that was originally installed on my M1917 Winchester rifle when I bought it. The E bolt would close on a gunsmith’s no go gauge but only closes about 80% on my field gauge. The W bolt closes about 50% on the same field gauge. Seeing the difference in closing percentage makes me think that the W bolt would probably not close on the gunsmith’s gauge.

I’ve not fired the rifle with the W bolt but I was able to successfully chamber and eject a dummy .30-06 round smoothly and it fits nicely inside the chamber with minimal movement.

The field gauge measurements on the E and W bolts were taken with the strikers removed.

Because I thought the E bolt was worn, I’ve been watching the internet all this time for a NOS W bolt, although the E bolt has successfully sent hundreds of bullets down range over the 4 years that I’ve owned the rifle without inflicting any damage to the rifle or the brass cases. In fact, I’m still reloading the original cases. I’ve had zero case-head separation and only one case that became unusable due to an enlarged primer hole. I re-sized the case and pressed in a bullet anyway and use it as my .30-06 dummy round.

I’d be interested to hear the story about the long chambers.

[lyman]

if the field gauge a commercial or USGI one?

either way, you measured correctly, stripped bolt (extractor off?) and did not close,

you could run a no go thru and see, if you wanted, at 50% of field, it may not close on it,

[Merc]

Commercial or USGI? Good question. The label on the box says it’s a .30-06SPRG and the mfr is Clymer. The model is CLY1015.

[lyman]

commercial,

may want to remove the extractor to check, but thinking you will be good either way

[Merc]

I removed the extractor and striker and checked it again. Still 50% closure. Aren’t headspace gauges set to commercial specs always a bit tighter than milspec gauges? Assuming that’s true, a military bolt that passes a commercial gauge should be ok. It’d be nice to have a milspec .30-06 gauge set. Any idea who handles them?

[fguffey]

I removed the extractor and striker and checked it again. Still 50% closure. Aren’t headspace gauges set to commercial specs always a bit tighter than milspec gauges? Assuming that’s true, a military bolt that passes a commercial gauge should be ok. It’d be nice to have a milspec .30-06 gauge set. Any idea who handles them?

Military? Commercial? What is the difference? Before SAAMI: I sold most of my head space gage, I had a few that disappeared because someone stole them; but I had both commercial and Military. When changes were made it was not like waking up in a different world, we all woke up in the same world but someone moved the datum. On the old head space gage the datum was at the case body/shoulder juncture' on the new head space gage the datum was on the shoulder and was determined by a round hole/circle. The round hole circle diameter became .375", .400" and .410" for many chambers.

I have never found it necessary to remove anything from the bolt when checking the length of the chamber from the datum/shoulder to the bolt face.

F. Guffey

[lyman]

I removed the extractor and striker and checked it again. Still 50% closure. Aren’t headspace gauges set to commercial specs always a bit tighter than milspec gauges? Assuming that’s true, a military bolt that passes a commercial gauge should be ok. It’d be nice to have a milspec .30-06 gauge set. Any idea who handles them?

no,

like Fguffey said,

same gauge, but the commercial measures from a different point,

example, and going from memory, 1.940 is go, 1.946 is no go, 1.951 is field on a military headspace gauge, (I have a go and field, lost my no go,,,)

bought a set of Commercial and the numbers are different (longer) but measure the same, (bolt closure)

military are usually cut so you do not have to remove extractors etc,