Bolts and headspace

[Orlando]

Two different NOS 65 series bolts, No Go gauge, surprised to see that big of difference in headspace with the same series NOS bolt
http://i47.photobucket.com/albums/f197/Garandlover/misc/Picture550.jpg
http://i47.photobucket.com/albums/f197/Garandlover/misc/Picture551.jpg

[Dave]

What is that receiver you got there?

[Orlando]

What is that receiver you got there?

http://i47.photobucket.com/albums/f197/Garandlover/misc/Picture557-1.jpg

[timshufflin]

And both bolts perfectly safe.

[Orlando]

And both bolts perfectly safe.

I realize they are safe.
I have used longer bolts before the get a used barrel to headspace ,just found it odd that there was that much differnce between the same series bolts.

[melloman]

That's a pretty big difference to my inexperienced eyes. I would feel much better using the one in the bottom pic but I wouldn't hesitate to use the one in the top pic.

[ordmm]

Oh please,,,post this on the CMP site...should result in a couple hundred answers. LOL

Feel evil tonight after seeing the lengthy discussion on CMP about how to rig a web sling......

Great pics by the way. In a way kinda amazing they could run the tolerances consistantly in the day of hand crank machines versus CNC.

[13Fox]

Please stop using your gauge stretcher just to have something to take a picture of!:p

[canes7]

There was a write-up in one of Clint McGee's (from FA I think) about measuring the distance it would take for the bolt to close to determine how much more reaming needed to be done. You can apply that equation here to tell the HS difference in the bolts. I really don't think it'll be all that much.

[deputy85]

Someday i may come to regret it, but i quit the headspacing of bolts, now ive only been doing this garand thing for 10 yrs and only been thru about 35 rifles but i never found one that didnt headspace,,sure someday i know i'll regret it,,,

[canes7]

I had one so loose that you could put the field guage in and it would rattle.

[jak]

Someday i may come to regret it, but i quit the headspacing of bolts, now ive only been doing this garand thing for 10 yrs and only been thru about 35 rifles but i never found one that didnt headspace,,sure someday i know i'll regret it,,,

I got a garand from CMP that would not close on the "go" gauge with the bolt that came with the rifle. Tried every spare bolt I had and it would not pass. I finally reamed the chamber. Looks like CMP swapped the barrel and never checked headspace.

[13Fox]

To further on what jak says, I also received two SG WRAs that I hand picked at the South Store that had the CMP SA replacement barrels on them and the go guage wouldn't close on them. I then cleaned the chambers even though they looked virgin clean and the bolts then closed. My guess is perhaps a film of oil? Further reinforcement about finger pressure only???

[timshufflin]

I've had three CMP specials come to my shop, bolts did not remotely close on go gauge. I can only pray that I have never let one leave here like that, unless the customer wanted it like that. I think that it's important to note that the CMP probably deals with as many rifles in a day as I do in a year. Odds are odds, and unless you are so vigilant, you can't buck math unless you're really good.

[Dave]

I've had three CMP specials come to my shop, bolts did not remotely close on go gauge. I can only pray that I have never let one leave here like that, unless the customer wanted it like that. I think that it's important to note that the CMP probably deals with as many rifles in a day as I do in a year. Odds are odds, and unless you are so vigilant, you can't buck math unless you're really good.

I've had a number of garands with short headspace over the years, far more than ones that are worn and eat a field gage. Most of these were WRA's with WRA barrels. Oddly enough, my last M1 Carbine restoration was a 7mil WRA that I put a WRA barrel on(to replace a heavy struck Blue Sky) and would'nt ya know it, damn thing is also short on headspace. I even tried bolts out of a dozen other carbines, all different makes, all still come up short headspace. It sucks because I've never been able to shoot this one. I don't want to buy a reamer just for one carbine. Tim, you got a carbine chamber reamer? :)