I went to the range the other day to put a couple pistols through their paces, and randomly grabbed some boxes of my "range ammo" without looking closely beforehand.

The new guns tried out- my worn-in P226, which is a rough looking shooter but in good shape where it counts, and my son's friend brought his new Shield. My son also brought his CZ 75.

My son's friend brought a box of WWB, and the rest was Sellier and Bellot 115 gr, and then Yavex 124 gr FMJ. The Yavex I got on sale awhile back at Bud's, and the boxes look very similar to Blazer Brass (black and gold boxes, similar layout etc). It is made in Turkey, has green lacquer sealing the primer and cases, brass 124 gr FMJ, non-magnetic.

Everything went as expected, until we started in on the Yavex with the fullsize guns; and the change was very noticeable. The report went from a normal "bang" to a deeper "boom" like a 45 almost, and we were getting 10 inch fireballs with each shot, something I normally don't see with the CZ. The Sig is new to me, but it went from a normal type range experience to spitting fire too. No problems cycling for either gun, it did seem to have more recoil, and accuracy stayed fine... if anything it might have improved

The difference in ammo was noticed by others, not just us. A couple of people who were there and previously not paying attention stopped and looked as we put a few mags through the Sig and the CZ.

It was a pronounced enough difference that my son's friend didn't run any through his Shield, said he didn't want to beat the gun up unnecessarily... he wasn't being silly, just careful since he was just putting the first couple mags through it.

I know S&B tends to run hotter than WWB and Blazer, and I've shot some of the white box S&B with the NATO stamp, and that didn't seem to act like this Yavex stuff either. It WAS consistent, just consistently "more" than the other stuff. The guns were pretty clean after shooting, his Shield (with the WWB) was dirtier, even though it wasn't shot as much.

Anyone else shoot this, have similar experiences? Is the flash just the powder burning more visibly?

Thanks for any input; I think I'm going to earmark this stuff for just our CZs and my Sig. I don't want to rattle some of the older guns apart...