I'm still bothered by experience vs. theory, especially what I read concerning the new S&W 460 XVR. So, I bought a new book Understanding Firearm Ballistics by Robert A. Rinker ISBN: 0-9645598-4-6.
A few excerpts from the book:
"Recoil increases as the square of the velocity". Well, we knew that.
"Recoil also increases as the square of the bullet's weight."Whoa, this is big news. I thought it increased only to the first power. Now what people have said that they felt shooting the heavier bullets makes a lot of sense.
"But, it decreases only to the first power with the gun's weight so a change in the gun's weight has much less effect."
The formula he gives for Recoil Energy is:
RE = 1/2 GW (bw*bv +cw*C/7000)2
Where:
RE = Recoil Energy in ft.lbs.
W= Weight of gun in lbs.
C= Constant (4000 f.p.s)
G = Gravitations constant (32.17 ft./sec./sec.)
bw = bullet weight in grams
bv = bullet velocity in f.p.s.
cw = power charge weight in grams
I also thought it was interesting that he said the weight of the powder charge has to be considered in the recoil energy.
"High velocity .22 centerfire cartridges, such as the .22-250 , will receive as much recoil from accelerating the powder charge as from accelerating the bullet."
He also mentions that the average person can handle 15 ft. lbs of recoil without discomfort, which is what we get from shooting a .44 Magnum with a 240 gr bullet and 22.5 grs. of charge out of a 3 pound gun.
What I find interesting is the .357 Magnum with 158 gr bullet in a 2.1 lb gun has recoil energy of 10.1. Okay, doing the math on the S&W 340PD with its weight of 12 oz. gives us a RE of 27 ft.lbs. Now I understand the remarks people have made when shooting this gun that usually start with the word "mutha".
Well, I'm not sure I understand all this stuff, but it is making more sense, and follows in-line with what some people have experienced shooting heavier bullets.
