WTB IBM Flat Bolt

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   In need of an IBM Flat Bolt.  My AOB Flat Bolt will no longer pass the "Go/No-Go" Test.
If anyone has a true USGI, WWII, IBM that they are willing to part with, I will give it a good home in an early (Nov-Dec 1943) IBM rifle.
Please feal free to contact me by posting here or through PM.

Reason for need:  I have swapped bolts between both of my IBM carbines and the problem follows the bolt.  That tells me 2 things.  #1 My problem is not the Barrel.  #2 My bolt is at or close to "Effective End of Life" and should be respectively retired for the sake of Safety.

V/r
Da1Chief

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Da1Chief Members Profile Send Private Message Find Members Posts Add to Buddy List On Point Joined: Oct 16 2021 Location: Suffolk, VA Status: Offline Points: 127	Post Options Post Reply Quote Da1Chief Report Post Thanks(0) Quote Reply Topic: WTB IBM Flat Bolt Posted: Mar 14 2022 at 6:01pm
	In need of an IBM Flat Bolt. My AOB Flat Bolt will no longer pass the "Go/No-Go" Test. If anyone has a true USGI, WWII, IBM that they are willing to part with, I will give it a good home in an early (Nov-Dec 1943) IBM rifle. Please feal free to contact me by posting here or through PM. Reason for need: I have swapped bolts between both of my IBM carbines and the problem follows the bolt. That tells me 2 things. #1 My problem is not the Barrel. #2 My bolt is at or close to "Effective End of Life" and should be respectively retired for the sake of Safety. V/r Da1Chief
	Very respectfully, Da1Chief DPC,RMC,ITC(SW) USN Retired

Rebel92 Members Profile Send Private Message Find Members Posts Add to Buddy List Grunt Joined: Jul 20 2021 Location: Hattiesburg, MS Status: Offline Points: 541	Post Options Post Reply Quote Rebel92 Report Post Thanks(0) Quote Reply Posted: Mar 14 2022 at 7:23pm
	so it closes on both the Go and No Go?

Da1Chief Members Profile Send Private Message Find Members Posts Add to Buddy List On Point Joined: Oct 16 2021 Location: Suffolk, VA Status: Offline Points: 127	Post Options Post Reply Quote Da1Chief Report Post Thanks(0) Quote Reply Posted: Mar 16 2022 at 8:17pm
	Rebel92, Yes, that is exactly what I'm saying. I have 2 sets of Head Space Gauges. Set #1 is a Forster and Set #2 is a Clymer. (Both are NEW) Both the Forster and Clymer "Go" Gauges allow the bolt to fully close into the Battery position. With Forster "No-Go" gauge the bolt will again fully close into the Battery position. With the Clymer "No-Go" gauge the bolt will go fully forward. However, the Lug stops about 3/4 of the way down and will NOT go into full Battery position. It's just a "Hair's Breath" away from full Battery. For the Record... I checked each with my digital caliper and the measurements are as follows. The Forster N0-Go measures 32.93mm or 1.2965in The Clymer No-Go measures 32.92mm or1.2960in I would really like to know how something shorter stops it and something longer doesn't. The only thing I can think of is the Clymer has a head on it shaped like a bullet and the forster doesn't and that somehow is the difference. That is why I say it "Fails" the Go/No-Go test. V/r Da1Chief
	Very respectfully, Da1Chief DPC,RMC,ITC(SW) USN Retired

W5USMC Members Profile Send Private Message Find Members Posts Add to Buddy List Moderator Group Joined: Apr 29 2017 Location: Missouri Status: Offline Points: 2958	Post Options Post Reply Quote W5USMC Report Post Thanks(0) Quote Reply Posted: Mar 16 2022 at 8:57pm
	Chief, I would not replace a bolt based on any No-Go headspace gauge failure. You need to check with a Field gauge. Forster Field gauge is 1.299 and a USGI Field gauge is 1.302. If it fails with the Field Gauge, then maybe there is an issue, and you could look at replacing the bolt which may or may not solve the problem.
	Wayne USMC Retired NRA Life Member

Rebel92 Members Profile Send Private Message Find Members Posts Add to Buddy List Grunt Joined: Jul 20 2021 Location: Hattiesburg, MS Status: Offline Points: 541	Post Options Post Reply Quote Rebel92 Report Post Thanks(0) Quote Reply Posted: Mar 16 2022 at 9:01pm
	I was about to say the same thing, Wayne. I have read and been told (by the legend Mr FloydtheCat him self) the same thing. I actually bought all 3 headspace gauges, and all but one of my carbines “fails” the go/no go test, the only one that doesn’t fail is my mixmaster! None close on the field gauge with their respective bolts however. And the ME’s are 0, 1.5 &1.5 so they have obviously not been used heavily! Don’t condemn the bolt. I was concerned at first but had knowledgeable people on the forum talk me off the cliff.

New2brass Members Profile Send Private Message Find Members Posts Add to Buddy List Moderator Group Dan Pinto, Photo Editor Joined: Nov 29 2015 Location: CT Status: Offline Points: 4655	Post Options Post Reply Quote New2brass Report Post Thanks(0) Quote Reply Posted: Mar 16 2022 at 10:10pm
	There are guys here that know their stuff. You will see that commercial sized gauges and military sized gauges may not be the same or use the same terminology for the same size gauge. Here is what is in the manuals TM 9-1276 FEB 1953 pg111 1.290 is the Go gauge, the bolt must close on this. if not the chamber must be reamed. 1.298 if the bolt closes on this without a perceptible bite the carbine is not acceptable and returned to stock. from there you would need a test bolt to check headspace. a test bolt is not an actual bolt, it is a gauge shaped like the bolt to exact specifications. basically they want the headspace as close to 1.290 when re-barreled with the test bolt. under no circumstances should the headspace exceed 1.295 when re-barreled and using test bolt earlier TMs use 1.300 as a maximum headspace ant the gauges are different with different part numbers carbines whose headspace is less than 1.302 with a component bolt (bolt to be used) and does not close on the 1.302 gauge are acceptable for domestic and overseas use. The commercial head space gauges, as I understand it, are not as lenient as the military counterparts Better to stay on the safe side.
	Club Survey Saginaw Receivers

Da1Chief Members Profile Send Private Message Find Members Posts Add to Buddy List On Point Joined: Oct 16 2021 Location: Suffolk, VA Status: Offline Points: 127	Post Options Post Reply Quote Da1Chief Report Post Thanks(0) Quote Reply Posted: Mar 17 2022 at 6:24am
	Thank You All for the Advice. I will take it and NOT change out the bolt. It was tearing me apart to take the flat bolt out and replace it with a round (IBM Flat Bolts are impossible to find). You guys have set my mind to rest. My flat bolt stays until my gun smith tell me otherwise. Again, Thank You All Very respectively, Da1Chief (Sandy to my Friends)
	Very respectfully, Da1Chief DPC,RMC,ITC(SW) USN Retired