Close. I found 65gr. 3F to be about identical in speed and power to 75gr. 2F GOEX in my .40, if using slippery lube.
In the .45 GM barrel, those similarities occurred with 75gr. 3F GOEX and 85gr. 2F GOEX- identical velocity, impact and group size if using LHV or Hoppe's #9 Plus BP lube/solvent.
Due to the larger bore (I hope) and thus MUCH greater expansion ratios due to bore size, I would expect 105gr. of 2F to be equal in velocity to 90gr. 3F.
This pretty much depends on bore size, though. In my .69, last time I tested this - few years back, 2F produced higher velocities than did 3F, however the 3F recoiled more sharply AND produced
higher pressures, judging by the recovered patches.
The higher pressure was evidenced by the patches I was using. I suspect the muzzle pressure was less with 3F, however the breech pressure was higher due to it's faster burn-rate.
I did not test over 125gr. 3F in the above testing. I felt the pressure generated by higher loads of 3F than 125gr. was more than I wanted to subject my rifle to.
I'm going to have to do that test again. I cannot remember the actual numbers, just that 2f produced not only higher velocities, but better accuracy - as I expected. The 125gr. charge of 3f actually
burned the patch in the odd spot. I've never had that before, with this rifle, with this material, yet I have tested to 200gr. 2F- normal patches resulted.
