Chris,
Sorry for the delay in replying.
Here is an example of what I think might be "hammer bounce".
Normally when striking a die with a hammer, you have a power down-stroke and a slight "lift-off" stroke to get the hammer face off the die after the stamping-stroke.
( I guess this would not be the case if using a "dead blow" hammer...???... )
I was surmising a hammer can come down again and rest on top of the die and make a 2nd. impression...a bit lighter in force and maybe not at the exact place as the original stramping...if the original hammer stroke rebounds back to hit the die a 2nd. time
Take a look at the "2" on the E/2 of SN-4685. The die moved a bit before the 2nd. impact and rotated some so only the "2" was the repeat impression.
How else could we explain the 2nd. imprint ? Are there any other ideas as to what would cause that ?
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