I know it was a USAF specific round, made for Security Police and carried by them in place of M41 ball. It was made at Lake City.

The bullet, a regular 130 grain metal case was unusually deeply seated and heavily roll crimped.

Questions:

1. When was it first issued.

2.Who were the first units to receive it.

3. Would the deep seating and heavy crimping make the bullet easily recognized when retrieved from a backstop?

This is what I could find on the cartridge-

A request for more powerful .38 Special ammunition for use by Air Police and security personnel resulted in the Caliber .38 Special, Ball, PGU-12/B High Velocity cartridge. Issued only by the U.S. Air Force, the PGU-12/B had a greatly increased maximum allowable pressure rating of 20,000 psi, sufficient to propel a 130-grain FMJ bullet at 1,125 ft/s (343 m/s) from a solid 6-inch (150 mm) test barrel, and about 950–980 ft/s from a 4-inch (100 mm) revolver barrel. The PGU-12/B High Velocity cartridge differs from M41 Special ammunition in two important respects - the PGU-12/B is a much higher-pressure cartridge, with a bullet deeply set and crimped into the cartridge case.

located here: http://www.liquisearch.com/38_special/history

My guess regarding your third question would be that "it depends" upon what other ammunition is being fired, or has been fired, into the backstop from which you are recovering spent bullets. I'd bet that the crimp marks would remain distinguishable unless the bullet hit something really hard (rock, concrete, metal, etc.) that caused it to break up. I also believe that Remington made it too, as there are boxes (or at least images thereof) bearing the Remington name. See the first post in this link: http://www.usmilitariaforum.com/forums/index.php?/topic/75410-38-special-ammunition-box/

 

Anyone who believes GT is all fluff and coarse jokes would do well to read these posts...the depth of knowledge of GT members is quite extensive!

 

Disclaimer: all dates are approximate, as my memory isn't what it used to be...

I think the first specs for PGU/12-B were written in the mid-70s, and I know it was already being issued at my first base of assignment when I got there in 1980. M41 ball was phased-out within a year or two, but was re-issued in limited quantities in the mid-80s for use in AFOSI (Air Force Office of Special Investigations) 5-shot .38 revolvers (S&W model 36). Testing by AFOSI HQ showed the PGU would beat the little J-frames to an early death, so for the remaining time they were used, they were filled (training and qualification) with M41 ball.

Changeover dates in items like duty ammo were usually done with instructions reading something like "Beginning on date ##-XXX-####...", and ending with "...to be completed NLT date ##-XXX-####" (NLT = Not Later Than). For this reason, while you can probably find out which units got "issued" the ammo first (delivered to their ammo storage point or armory), that might not have much bearing on which units got it into the hands of the end-user first. Smaller bases with fewer users would probably field it very quickly; large bases with hundreds of users might take longer to get everything swapped-over.

Here is a visual comparison of the two rounds (click to enlarge):

The radical deep-seating of the bullet made it very easy to visually ID the PGU-12/B load. I think it was the same bullet (definitely the same weight, 130 grains) as the M41, they just seated it much deeper and applied a cannelure to the case to force it into the bullet's crimping groove, THEN they crimped the mouth of the case over the bullet's ogive. It was definitely hotter-loaded than the old M41 and the WW 148 factory wadcutter loads we formerly used for training. Although I've also read that Lake City made PGU-12/B ammo, the above rounds were both produced by Winchester (WCC headstamp), with the M41 showing a 72 year on the headstamp, and the PGU-12/B showing 89.

We still used the WW wadcutter loads for training for several years until it ran out; eventually, we switched-over to training with the PGU-12/B load for all users of model 15s and 56s (with M41 ammo for AFOSI agents in their model 36s). There was much sniveling when the changeover occurred; the wadcutters were VERY accurate and mild, and the PGU turned the model 15s into raging beasts (according to the older cops). :supergrin:

 

The ammo we were issued in 1982 looked a bit different than the above deep seated round. It had a star shaped crimp with the bullet nearly all the way inside the case. It was quite a bit more powerful than the standard load, nearly as fast as a 9mm ball IMHO. I liked it a lot better than the M41.

 

II'd venture to say tha tteh reason for deep seating was not likely for the identification of recovered bullets but for distinguishing the round itself from standard M42 bsll ammo.

The deep seating would have an additional benefit of boosting pressures and increasing velocities without having to use more powder.

 

Yes, I think they just seated the bullet deeper to increase pressure. It would not cost any more than the standard load.

There was a rumor that some SPs did not like the low powered M41. They would pull the bullet and dump another full load into the case. Not a good idea. The load was supposed to be 3.5 grs Bullseye. The heavy crimp was thought to be a way of preventing this practice.

Frankly, the M41 looked like a 130 gr .356 bullet, used in the 38 Super, loaded in a 38 Special case. This was supposed to be for the aluminum cylinder Airweight revolvers made up for the Air Force. After it was determined the cylinders would crack, those were pulled from service. For some reason, they kept the low powered ammo.

 

Thanks! I knew GT folks could help....