>>64176446
>"thumb groove" is a bs feature for importation
Interesting theory but you have to place your thumb there to keep it parallel with your index finger
>use a conventional thumbs high grip and isosceles
The frame wasn't designed for that. Are your hands double jointed?

>>64176453
lol

is glock the best grip angle? Just like how the Soviets were putting vertical pistol grips on their AKs and SVDs?