Speaking of parts - a bolt question

[imarangemaster]

There was a seller on Gunbroker selling a USGI Carbine bolt with a "X" stamped prominently in the top of the bolt. IIRC, that means it was a reject bolt that was out of spec.

Information

Warning: This is a relatively older thread This discussion is older than 360 days. Some information contained in it may no longer be current.

[ChipS]

I believe this has been adddressed before on this forum, specifically re late IBM (or maybe QHMC) round bolts, I think. Do not take it to the bank but I believe the X was a mark indicating that the bolt had been re-heat treated to correct an original manufacture heat treating defect. The bolt was not ultimately rejected and I believe there was a definite, identifiable time period/serial number range in which these 'X' bolts were assembled and issued. I think this has been adddressed in Carbine Club newsletter(s) and some of the more advanced collectors here will surely be able to comment with more authority.

[imarangemaster]

Thanks

[Bubba-7]

It was a round bolt without all the latest design changes.

[Bruce McAskill]

AND it was not a rejected bolt. They were used in production. There is nothing wrong with them and as Bubba 7 said they just did not have the latest updates on them.

[painter777]

From BQ...

"The X had nothing to do with heat treating. It means the bolt does not have all the revisions incorporated into the round bolt design. "

Speaking for myself,
I have only seen the AOB Type III round bolts with the X marking.
My IBM 3,849,505 came with X marked round bolt. IBM barrel- no date.

Does anyone know if there were other makers marked with the X?

Thx,
Charlie-painter777

[Bubba-7]

Besides IBM, I have seen Inland and Rock-Ola round bolts with an X. The Rock-Ola was on top, like IBM, and the Inland was on top of the right lug.