Wether you push a lower mass object at higher rates of acceleration, or higher mass objects at lower acceleration rates you could end up with similar results regarding felt recoil forces.
My point that was explained really didn't reflect "mass + acceleration", per se. Here is a better way to explain it: Remember, there are approximately 734gr. to an ounce. When you are launching a 1 7/8oz. payload at 1210 fps, this is what I think: 734grs. per oz. x (round up) 2 oz. =
1468 grs. total. Take into account, we're talking about 17/8 ounces, so we'll say 1450 grs. Now, think in these terms: What would apparently kick more in a gun, a payload of 1450grs. going 1210fps, or say for instance, a 30-06 180gr. load going 2700 fps. Those are the figures that I take into account FIRST.
Next, the powders used. When you combine a faster burning powder, with a heavy payload, that adds to the recoil. A fast burning powder's gases expand more rapidly than a slower burning rifle powder. Here too, the rapidly expanding gases have a heavier mass to work against. Remember Newton's third law I believe: For every action there is an opposite, and equal, reaction. Try this, burn 10grs. of Alliant Unique, and try burning 47gr. IMR 4064. You will see the difference, if you will, of the rate of combustion, hence, the rapidity of gas dispersion. It has also been proven that a lighter bullet going much faster, can have more terminal ballistics than a heavier bullet going at a slower rate of speed, under certain circumstances. The rifle powder's characteristics are a more controlled release of gas (and due to the heavier charge, more gas is created.) Whereas the Unique, or whatever pistol powder that makes excellent target loads for shotguns, will burn much more vigorously (therefore, a given amount of gas expands in a quicker frame of time.)
I'll go more in-depth to the purpose of a slower burning powder here. The benefits of a slow burning powder promotes a longer "burn-time" in the barrel, which keeps a longer source of pressure to allow the bullet to continue to accelerate. Much like a progressive pushing of the gas pedal on a car. And these characteristics keep the operating pressure reasonable as well. And because of the slower burning, the recoil is gradual. This may not belong here, but look at reduced loads for rifles. They use a faster powder, and they have a min and a max load. They are tested to the maximum SAAMI pressure standards for certain cartridges using THAT particular powder.
Now, the quicker burning powder's play into ballistics. Please forgive my rambling, but this stuff takes alot to explain!! I have read there are many reasons for their purpose, so I'll make it short and maybe someone can add on to them. Anyway, the quicker ignition causes more gas to be dispersed in a faster period of time. Therefore, in a shotgun, the payload is heavy, with a fast burning charge of powder, which means it has a more violent reaction, which is felt by the shooter. When that happens, the pressure can also run too high if too much powder is used. See how the magnum pistol cartridges use a "slower" pistol powder than do standard cartridges? That is because their capacity relative to their powder "needs for magnum status" would promote pressures higher than is safe. So a slower powder is the cure. And make sure, as they say, to crimp them good, so they burn more consistently, and cleaner. Therefore, the reason behind all this sums up to what needs to be done, with how much, what pressure limits are set, and how heavy the payload. Whew, I'll quit for tonight, and being my knowledge is limited, I may have stated in-accuracies. Remember too, these are just somewhat accurate examples that try to deliver a particular idea to the reasons behind why a SG recoils more than a rifle. If there are any errors, like every first print in books or whatever, feel free to correct or critique them. I'll humbly accept them in whatever article they represent. God bless you all for bearing with me.
Patriot
