from the old forum:
Someone wanted to know if hammering on the barrel causes the strain gage to record 100,000 psi pressures. As usual, I would rather collect hard data than argue armchair theory.
The usual Rem M700 30-06, gage #2, mounted on the bottom of the breech, supported in a Steady Point rifle rest while I abused my prized elk rifle.
The PT trigger was set to 2, even though I normally set it to 5.
I hammered on the muzzle repeatedly using a one pound ingot of cerrosafe (if you want to hammer on your barrel with a sledge hammer, be my guest, but I'm going to use something a little softer.) The PT refused to trigger.
Then I grabbed the muzzle and yanked it side to side and up and down and all around, as hard as I dared. It seemed to be flexing a good 1/4" in each direction. The PT refused to trigger.
The PT trigger was then set to 1, which is as low as it can go.
More hammering. The PT refused to trigger.
More bending the barrel. This time I tried harder, flexing it about 1/2". I got the trace to trigger a single time. I kept trying, but it refused to trigger again.
I hammered some more, but it still refused to trigger.
Here is the one and only trace that occured while bending the barrel. Some spike, eh?