drewm@p40
Member
My question is this, between 165 grain and 180 grain 40s@w is there a noticeable difference in felt recoil
It depends on how it is loaded. At equal MV, the 180gr kicks harder.
At equal Power Factor (momentum) the 165gr has more MV and energy and kicks harder.
In competitions where Power Factor is required, 180gr is the favorite.
Interesting, I don't notice that at all with equal power factor. I've loaded 180g 40 bullets to shoot 730 fps (2.7g Clays) and 120g 9mm bullets to 1100 fps (4.2g Unique) and shoot them through the same gun (M&P40 swapping between 40 and 9 barrels) and the recoil is the same as far as I can tell. Both are PF=132.
I'm not surprised, for minor power and an experienced shooter, the difference is small. However, have you tried the 180gr vs 165gr, both at major power? I have, and it is noticeable, though not devastating. Here's a handy calculator: Recoil Calculator Felt recoil, as opposed to calculated recoil, is HIGHLY subjective and shooter dependent.
I've used this as a standard (also used 3.0g Red Dot) so I can get a feeling of what a 9mm version would feel like with other 40 cal guns.
I thought that the competitive groups try to run things equally by trying to set equivalent recoil. That's why they came up with Power Factor as the equalizing quantity and not muzzle energy.