I don't claim to be an expert, just bringing off the top of my head high school physics,coupled with a few google searches. Actual energy imparted to the shooter is, well, pretty simple.
Newtons 3rd Law of Motion will always apply: For every action there is an equal and opposite reaction. We're attempting to push this little peice of lead from motionless into high speed, and so it pushes back, it has to. A 150 grain .308 overtop 60 some odd grains of powder will push back a constant amount, whether it's out of a 6.5 pound gun or a 15lb. But, since that bullet has to push on that gun, the gun itself will push back until it has to move. When it moves, it gives us felt recoil. Lighter (less mass) guns are easier to move, transfering more energy to the person pulling the trigger.
Put a bigger peice of lead on the end of that, and you'd find (even if you can't feel it too readily) that there would be more felt recoil. Since you are trying to push a heavier object (more mass), it will take more force to move it, therefore pushing back with more force. Increase the mass of the lead in the same gun, (i.e. 220gr vs. 150gr .308) you may find a slower kick, rather than a sharper one (if the powder charge remains the same) since it will not accelerate as fast. When we up the powder content, say in a .300 Wby Mag with 150gr leads, we'll probably find not only a harder kick (more felt recoil) in the same wieght (mass) gun, but a sharper one as well. We're taking the same bullet but accelerating it much faster.
Conventional means of controlling a a harsh kicking rifle, say large magnums with a few hundred grains of lead to push out, plus a large powder charge is to make a heavier gun, since (imho) it presents simpler way to reduce felt recoil. You are pushing more mass, with more energy and therefore, it has to push back more. Simple way around that, make the gun push back more, therefore pushing you less. Until you have to hike for miles and miles.
As Monashee stated, automatic and semi automatic's use the guns energy (gas or inertia) again to cycle the action. This means less energy is transferred to the shooter. Like more gun mass, this only reduces felt recoil. The same hunk o' lead over the same amount of powder will still produce the same push backwards when touched off. Same with a muzzle brake, it uses the expanding gas coming out of the barrel to reduce felt recoil by just pushing the gun forward, in a fashion. Another, yet perhaps just as punishing as heavy recoil, way of managing it.
Glyn, I can't find anything mathematical that would support your theory other than being a longer and bigger barrel, it would just add mass to the gun, and mass being a large part of the picture. But, it certainly open up the characteristics of recoil due to overall gun design as compared to mass/energy relationships.
What can't be found too readily in text books and google searches is what H4831 talks about. Stock design. I almost picked up a book today at Nosale about gun fitting, and I kind of wish I had now. This part gets me interested. My Dad's Parker Hale .303 also kicks up, a lot more than my Lee Enfield .303, with the forestock all 'sporterized' Same action, different stock. We also had a Parker Hale in a .270, (not the Lee Enfield action) a long time ago, which did not kick up, as my Dads did. Stock design does play a major part it in, but so far all I've learned has come from small bits of first hand experience. I can see how a large drop at the heal as mentioned can change the direction of the recoil. I've read before that the Win88, even in .308 has more of a kick than most people would anticipate, but never having handled or fired this gun, I can't say for sure. H4831, have you found other guns with similar shaped stocks to fire this way as well? I'm going to take a look at my Dad's PH and compare a little to the other guns we have, and see if it has more drop as well.
As to actually kicking harder, mathematically it's.. Well, I hate to say impossible, but with equations that have been around and proven for so long.. Well, you get the point. That's one thing about physics. All the math in the world can say otherwise, but when she kicks, she just kicks.
Jesus, this is too long. I think I'm done for a little while.
