I have had an issue with a box of Tulammo .380 I tried (back in July 2013). In the course of shooting a number of different rounds through a new-to-me Browning/Beretta/FN BDA, I shot some some Tulammo 91-gr FMJ. I expected blah performance. Similar ammos had been running from 950 to 1050 fps from this gun on this trip; I anticipated the Tula would be on the lower edge of that range. The range was 90°F and at 5950'>sea level, about 10% humidity. The chrono had been working perfectly with a half dozen previous types of ammo.
My first shot with the Tula read 1422 fps.
This struck me as crazy; certainly an error. No way
that happened, right?
So, I erased the shot and took another.
1229 fps. Then 1186.
Then 1412.
I took the ammo out of the mag, and proceeded to a WWB load, which chrono'd perfectly reasonably. Just for kicks, I ran some known-performance .22s thru the SR22 - the chrono was working fine.
Soooooo . . . I sealed up the Tulammo and thinking I might try it later in my locked-breech LCP. I never have: I speculate that the bo received a 9x19 charge in the Russian factory.
The gun in which I shot the problem ammo was none the worse for the wear - I fired another 50 or so rounds through it after that, with fine results. The velocity spread of those four rounds was pretty amazing, all things considering, but then so were the velocities.
I've not heard of this before, and most Tulammo I've used has been pretty crappy. Maybe this was just a bad lot. Heck, maybe I ought to measure the bullets to makes sure they didn't slip in some .363" Mak bullets - I don't know if those would cram into a chamber (I doubt it), but I'd imagine
that would raise pressures a bit.
I had tried another box (and probably another lot) through the LCP on an earlier excursion (c. 58 degrees F, same range, 20% humidity), and got totally expected wimpy results:
Tula 91-gr ball/steel case: M 883.3/ES 120.0/SD 47.56
Anyway . . . just thought you might be interested in hearing this tale.