G Forces from 9mm 357 44

[sirgilligan]

For Thanksgiving I was able to go home to the farm. I had my brother break out his Security 6 and Super Black Hawk. I compared them to a CZ 75.

I will let the images do the talking.

9mm - 6.5 G

357 Magnum - 11 G

44 Magnum - 17.5 G


I forgot what the loads were on the 357 and 44. Sorry should have noted that.

 

[Mal H]

How were those g forces measured? The instrument (your phone?) may not be sensitive to such a short lived acceleration event as a firearm exhibits. I believe they are off by a factor of at least 10 or more.

A relatively heavy rifle (.308 for example) will produce a g force in the high 100's or even 200 or more. I have heard that a .44 magnum with full house load will approach 1,000 g's.


[Added]
I went searching for a table of g forces for various calibers and found this at arfcom (the second post has the inclusive table):
https://www.ar15.com/forums/armory/Gun_mounted_PVS_14__how_much_recoil_is_too_much_/18-368820/

Note that they used a 4 Kg (8.8 lbs) rifle for the calculations so a much lighter handgun will have a higher g force for handgun rounds.

 

[sirgilligan]

Thanks for the link.

It is measured via an AppleWatch. Therefore, this is how quickly your wrist changed acceleration. So, it is a relative measure of felt recoil. From this you can see that just as we all have felt, the 44 is more than the 357 and the 357 is more than the 9mm and these numbers are not absolute, but relative values for comparison.

The links you give use the gun and the forces of the ammunition as the system.
With the Apple Watch, the system is the gun, the ammo, your hand, the articulation of your wrist, elbow, shoulder, and your entire body if you step backwards a bit, etc. The measurement is the rate of acceleration of the Apple Watch.

 

[sirgilligan]

The captured data also shows exactly when the shot happens by the peaks in the g-force. This makes measuring time between shots easy. Making a "force recorder" instead of a "sound timer" makes this app capable of measuring times between shots. A sound based timer can pick up sounds of others, etc.