I’ve got about 8 pounds of powder that I pulled down from some surplus Turk 8mm ammo. I weighed quite a bit of each one as I broke them down. The bullet averaged 155 grain (FMJ) and the powder charge averaged 48 grains of a square flake powder. I have reloaded these in new brass with 40 grains behind the same 155 grain bullet with very good results. They chronographed an average of 2600 fps with some a little less. Accuracy was suprisingly quite good.

I’d like to try this same powder with some Remington 185 grain soft points, but need some data on how to extrapolate a powder charge for this heavier bullet. I’m lead to believe this powder falls between 3031 and 4064, but I’m hesitant to believe this “internet gospel”.

Any input is appreciated.

On page 134 of Mauser Bolt Rifles, Olson records the Military 196 grain load used 43.9 grains of flake. So your 40 grain load should be a good safe starting place for the 185 grain bullet as well. On page 132, the 154 grain bullet load was 49.3 grains. That agrees closely with your findings. It is likely the Turks were trying to duplicate the German loading.

I've got some 1941 Turk. I pulled down 200 rds to use the powder and bullets in an 8x52R Siamese. It is loaded with 48.5 grains of flake behind a 154 grain bullet. It chronos at 2,910 FPs out of a 29 in. bbl.