Firstly, your photo did not come thru…Message:" Image or video Moved"
As to the headstamp,
SF Societe Francaise de Munitions (Maker/Loader) I Issy les Moulineax ; case metal supplier ( I-les-M is a small periferal town of Paris, and the “Moulineaux” refers to the original Water Mills there, it is part of SFM complex ( now closed down)
1 57 Ist Trimester, 1957.
Typical French Military headstamp.
Since there is no photo, can’t do any further ID.
Hmmm…I’m sitting here looking at it???
I’ll reload it.
Your yellow-base French .45 was converted to subsonic, using the existing components, by some firm in Texas. Don’t feel like walking the stairs to check through my massive .45 files, but I believe the name was “Exploraco of Texas.” So, the original French military loading has been converted, probably by slightly reducing the powder charge only, to an American commercial load.
So it was a “gunshow” load and not for any specific contract or purpose?
John is right.
No specific French contract but an alteration by somebody.
The fact to be converted into a subsonic round is funny because this ctge is already subsonic in its original loading
Idon’t really know what is meant by a “gun show” load. Not everything done to alter existing ammunition or produced by small companies is for gun shows. It was obviously made for a specific purpose, but it was a commercial purpose, not a police or military contract. JP is right that to mark it with the yellow base for a subsonic load is funny, since virtually all normal .45 hard ball ammo is already subsonic from pistol barrels. It could have been lightened further for SMG-length barrels. I don’t know if the longer barrel of some SMGs increases the velocity to above subsonic or not, and I don’t really know what the specific purpose was, except to know that this ammo was sold in this form in the USA commercially. I seem to recall another color base as well, but that may have been on 9 mm. I think the same company used an orange color base on something.
If I get downstairs tomorrow, I will try to see what I can find in my collection or notes. Too late, too tired and the knee hurting too much to do it tonight.
Edited to correct a spelling error only.
I’m happy to report that my memory served me well for once, and what I wrote on this “French” .45 coincides precisely with my notes on it. I also checked my memory about an orange-base version, and that round is a 9 mm Parabellum, loaded in an R-P case. It has most of the base painted orange, and was also loaded by Exploraco of Texas. The cartridge Weight of the 9 mm is 190.8 grains, which would indicate, going by the average weight of a 115 grain 9 mm cartridge (about 176 grains), that the very round nose bullet is 130 grains. Diameter of the bullet at the neck is a proper and precise .355".
These are the only two types of ammunition I recall ever seeing from Exploraco, but of course, they may have produced other ammunition products as well.