On the old Forum, there was a long thread concerning the “unknown” headstamp “C” that appears on .455 Webley Self-Loading cartridges, always either a blackened case “ball” round or a dummy. Many will not recall that thread either thru limited interest or joining only the new Forum, so I will review very quickly.
The Headstamp “C.17 I” on this cartridge has been regarded as unknwon. The rounds are odd in that they are loaded with Birmingham Metal and Munitions Co. Ltd. bullets (easily identified by ogive and base marking) and that on the “ball” rounds, the cases are always blackened. I reasoned that the “C” might well stand for “Colt,” since during that period, Colt made the Government Model Pistol for the British in caliber .455 Webley SL. Since that caliber of ammunition was not made in the U.S. Colt would have had to obtain any test material from England. Ball ammunition was not a problem. However, they would have needed proof loads (the proofing was done by British technicians, but at Colt, according to the terms of the contract) and functional dummies. While not a British marking, a backened case was a typical U.S. marking for a proof load, and Colt may have required the American identification marking to avoid any chance of a mishap during testing. Since, again, these “C” rounds only appear as bulleted live cartridges with a blackened case, and as dummies, it is not unreasonable to believe that they were made specifically for Colt, and I still hold that opinion. The blackened-case “C” rounds have a very stiff charge of nitro-cellulose powder, not the normal fine cordite found in .455 of the era. British author and authority Ken Elks reckoned that the charge represented a 50% over-load in pressure.
As to what the “C” means, I was convinced it was “Colt.” However, in researching headstamps for a recent thread about 7.62 x 54R headstamps, I found that the Government factory 1 (normal headstamp “G. F. 1” along with a date) was administered by none other than the Birmingham Metal and Munitions Company Ltd., whose bullets appear in the “C” headstamped .455 Webley auto cartridges. There is also a note by Labbett in his book on the .303 Cartridge that the “G” standing for “Government” often appears as a “C” on headstamps. This comment kind of hit me in the face like a wet rag.
Could the “C” headstamp actually indicate manufacture by Government Factory Number 1, at Blackheath, Staffordshire, which opened in 1916 and was administered by BM&M Ltd.? The coincidence of Labbett’s statement and the fact that the “C” headstamped rounds have a BM&M Ltd. type projectile is hard to ignore.
On the down side, the headstamp is simply “C” and not “C.1” or “C.F.1” on the black-cased, bulleted rounds. However, and this is starting to loom as a very big “however”, the headstamp on the Dummies is “DUMMY C 1 17” with the one not apparing as in a “Mark” number as “I” but rather as just a straight, vertical line. (There is no hook on the figure as this type-face shows. When typing the headstamp I had no way to make a straight vertical line). One of the questions about the dummy was why is was shown as a Mark I (C 1 on the headstamp) when it is not a specific Mark I pattern of dummy. Perhaps that should not be read as “C Mark 1” but rather as C Factory 1"!!?? Note that a similar question was asked about the black case in relation to its being a proof load; that the “I” designation would not be right. Well, I have an Eley military-headstamped proof load, and it too, uses a Mark I ball headstamp, but has a purple stripe across the base and came from the recent house-cleaning of the Birmingham Proof House.
Now I am about 33% each on three choices - Unidentified, period! Colt. government Factory #1.
Any thoughts from our knowledgeable British friends on this? I am sorry to reopen and older thread, but this begs to be discussed for those of us interested in British pistol ammunition.