sneaker wrote:Asking about shot specifically here though which has some give and flow.
It does but there is give an flow both ways. A barrel is not immune to this.
The shot will obviously give and move
more, but even if 99% of that energy is transferred with the shot and only 1% is absorbed by the barrel you've still got a bulged barrel.
This are moving so fast and with such energy in firearms there only needs to be an obstruction for fraction of a fraction of a second and the barrel will have to absorb some of it.