Thread: The Maths of Recoil

https://www.jbmballistics.com/cgi-bin/jbmrecoil-5.1.cgi

I have spent a while playing around with this calculator, which has powder weight as one of the fields you enter.

For example
7Lb Rifle, 165gr projectile, 2800fps MV, 41gr charge = Recoil Velocity:13.5 ft/s Recoil Energy:19.9 ft-lbs Recoil Impulse:2.9 lb-s

If you somehow managed to achieve the same MV with a 30gr charge (with all else being the same) your numbers would be: Recoil Velocity:12.5 ft/s Recoil Energy:16.9 ft-lbs Recoil Impulse:2.7 lb-s

Not an insignificant difference.

Originally Posted by SixtyTen

https://www.jbmballistics.com/cgi-bin/jbmrecoil-5.1.cgi

The jbm calculator is using an exit velocity of 4700ft/sec to calculate the contribution of the propellant.
I believe this was also the figure given historically in Sierra handbooks.