WWII M1911A1 Barrel

[Promo]

Johnny, all I wanted to say that it does not necessarily needs to be a ex factory marking and it could be that it's part of a European firing proof. Quite a lot of the M1911A1s in Europe bear such markings, not only the British ones. I'm mentioning this because Mikecp lives in Switzerland

[Johnny Peppers]

IMHO that would be ACP for Automatic Colt Pistol, there should be a .45 somewhere aswell

The conversation started from the information Mikecp gave that the barrel had AG1 on it, and it appeared you posted that it should be ACP. I replied that the AG1 was a heat lot number and had nothing to do with the caliber. I don't see the problem.

[Scott Gahimer]

Johnny, all I wanted to say that it does not necessarily needs to be a ex factory marking and it could be that it's part of a European firing proof. Quite a lot of the M1911A1s in Europe bear such markings, not only the British ones. I'm mentioning this because Mikecp lives in Switzerland

The markings shown in the original post are clearly Springfield Armory barrel markings. The marking in question is definitely a WWII heat lot marking originally applied at the time it was manufactured. It has nothing to do with firing proof marks.

[Mikecp@2022]

Thanks to all of you for your comments, so this kind of barrel is definitely a Springfield made with AG1 heat number probably a test proofing at that time, and this one was used as a field replacement or an Arsenal refurbishing replacement during WWII or post war, in mind to be resale to commercial.

[Scott Gahimer]

Heat lot markings had nothing to do with commercial sales. Springfield Armory had some trouble with their barrels being out of specification, During WWII production, heat lot markings were applied to some barrels. Some refurbished barrels had there heat lot markings removed when they were reworked and brought into specification. Some WWII SA barrels were also marked with tiny crossed cannons markings, too. But none of these barrels were manufactured for or originally marked for sale on the commercial market. I understand there is a language barrier here, and I am trying to be as clear as possible. Commercial sales had NOTHING to do with the AG1 heat lot marking. It was merely a heat lot marking...that's all.

[Johnny Peppers]

The S is for Springfield and the P is for the firing proof. As indicated in the earlier post, the AG1 is the heat lot number for the steel used in the barrel.

Here is a WWII Springfield barrel with the steel heat lot number D4. A few of the WWII Springfield barrels had the barrel drawing number C 3838-4 also. The C was the size of the sheet of drawing paper, the 3838 the sheet number, and the -4 indicated the 4th revision to the barrel.

[Mikecp@2022]

Well! I know my English is not academic as it should be, thanks to clarify those marking anyway.
So, colt has it's own marking COLT 45 AUTO and C EOP. Ithaca, US&S, Remington Rand used HS (Hight Standard) with few Colt barrel used early.) Singer made their own, and has It's own marking only P ( not sure)
So, Springfield barrels was never issued on one of these five manufacturers, only for field replacement during WWII or for military use later. Am I right?
Thanks

[Scott Gahimer]

No, some SA barrels were installed in 1943 Remington Rand pistols, but only those SA barrels manufactured at that time. SA also made barrels between WWI and WWII. Those between-the-war barrels were not used in new production WWII pistols.

[Mikecp@2022]

Thanks Scott for your infos...