Here is a Finite Element movie of a rifle's motion amplified by 500X when it is fired from a benchrest. This is a bit technical, but look at the analysis of Esten's Rifle here: http://www.varmintal.com/aeste.htm

Good Hunting... from Varmint Al

That's a decent computer simulation but in real life a barrel actually "whips" back and forth at the muzzle when watched at extreme high speed camera slowed way down. I guess it would be space prohibitive to show actual firing. You have the right idea tho.

Always knew the barrel whipped upon firing and generated some distortion to the stock. However, if that example that was given is actually what does happen to the whole combination at firing, you best have a real stout scope on your rig. I just find it very hard to swallow that the scope is subject to the degree of flexing exhibited here. Go back and take another look at it..............

Here is the same view with no amplification.

The deformations in the first movie are amplified by 500X. The actual movement of the scope objective is about 0.0015" at its extreme downward position. Also there is quite a bit of over-hang on the scope in the model and it is a 1" diameter tube. The amplified deformations are so one can get a relative idea of where the motions are taking place.

Good Hunting... from Varmint Al

A gunsmith told me years ago that a barrel reacted like a tuning fork. Later, I heard harmonics were also involved. Wouldn't that imply a wave, and thus there would be certain barrel lengths that (should) work better? Let the engineers chime in.

Holy crap, its Varmint Al.

I ran across your website a few years ago and spent many hours reading- very good stuff, its not every day that we get good well researched material from a trained engineer/scientist on gun stuff. Looks like you have lots of new stuff- I'm going to need to free up my schedule a bit[8D]