Gunboards Forums banner

Projectiles for reloading 7.7x58 Japanese

3.8K views 12 replies 7 participants last post by  Gregg  
#1 ·
#6 ·
I just measured the bullet diameter of a couple dozen various 7.7x58 and 7.7x58sr cartridges, ball, tracer and AP.
They all measured out at .310 and .311 diameter.

Pulled projectiles from 7.62x54r, 7.65 Argentine and 303 British are all suitable for loading 7.7x58.
All those projectiles are .310 to .311 diameter.
You can also use projectiles intended for the 7.62x39, but they are on the light side at only 123 to 125 grains, but they will work.

Japanese T99 rifle war time production bore diameters run all over the place from .310 to .316.
But, the Metford style rifling will shoot flat base bullets fairly well, no matter the bore diameter, with in reason.
Most Japanese T99 rifles will not shoot boat tail bullets well, unless the bore is tight in the .310 to .311 diameter range.