Originally Posted by Varminator 911
I was recently having a good natured discussion on another thread about whether cartridge case dimensions affect recoil. I don't think so but I've been wrong before. So educate me if I'm wrong.
My impression is that recoil is dependent on rifle weight, bullet weight and velocity, and weight of powder charge. There could be other minor factors affecting recoil but cartridge dimensions is not one of them.
The other view expressed, as I understand it, is that if all other things are equal, a short fat case will have more recoil than a long thin case. Reason being that the short fat case has a larger case head. Thus with equal psi the force pushing back on the bolt is greater. Thus greater recoil.
I feel that until the bullet leaves the bore, pressure in the case is pushing equally in all directions, including the base of the bullet, and these forces, fore and aft, cancel out. After the bullet leaves the bore the jet effect of escaping gases greatly affects recoil. But prior to the bullet leaving the bore internal forces don't affect recoil.
What do you guys think?
There are two kinds of recoil, Recoil energy (Total force backwards) and Recoil velocity (The speed at which the weapon moves backwards ) This is sometimes called "Felt recoil".
If you look at the formulas for calculating these types of recoil they do not include the case size
or shape. Only the bullet weight,caliber, powder in grains,velocity and the weight of the
Heaver bullets= More recoil, more velocity=more recoil, less weight of weapon= more recoil ,ETC.
The only reason to feel a difference between two cartriges of different shapes if all other
things are equal is the burn rate of the powder that is used. A faster burn rate that produces
the same velocity with the same bullet and weight of rifle will reach peak pressure faster
and increase recoil velocity and that might be mistaken for more recoil.
It is as Dmci Stated (Newtons law applies).
So even if it feels like it recoils more, if everything is the same it doesn't. Felt recoil can be
deceiving because even the fit of the stock can change the perceived recoil. Just like if you
hold a shotgun tight against your shoulder and fire it then hold it away from your shoulder and it will recoil more because in reality it weights less because you shoulder is not adding any weight
to the shotgun like it does when held tight.
I hope this helps explain your question.
J E CUSTOM