Pblatzz, that Turkish stuff you were shooting was made precisely to the specifications laid down in 1904 for the original JS load, which was the standard rifle loading in World War One. Shooting it through your Turk Mauser, you were getting VERY close to 2900 ft/sec with the 154-grain greased-steel-jacketed pointed bullet.
When this stuff hit the market in the States, I didn't have the money to bring in a batch. I was, however, able to beg 3 bandoleers of it from a fellow who runs a museum. I pulled down 30 rounds and put the charges and slugs into fresh Boxer-primed brass. Tested in 3 different rifles (a Gew 98, a Kar 98b and a Kar 98aZ) which had, collectively, been through 7 wars that we could prove, this ammo averaged just over 1 inch at 100 yards through the three rifles. That many people dismiss this stuff as garbage is down to one single factor: dodgy primers.
Note please that there was NO effort to re-uniform the charges: the charges were dumped directly from the Turk rounds into the newly-primed Norma commercial brass and then the bullet seated. The reason for this was simple: this was a test to see what that ammunition would do when it was fresh. It was VERY good.
The powder, by the way, was a square-flake type which could not be told from original German WW1 powder (I pulled down a German 1917 round to check).
Hope you saved some of that Turkish ammo, friend!
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