1974 die shift?

[warworn]

06CDBE61-A0FA-4BBA-A782-F3C8D7A8C162.jpeg (1.42 MiB) Viewed 369 times

Back of head and below chin, not sure.

[Bill in Burl]

No, MD, machine doubling

[momomomo]

die shift and md are the same, no?

[castor]

die shift and md are the same, no?

Machine doubling is the surname of mechanical doubling.

Yes your name “die shift is good” momomomo

Here is a short list of these mechanical doubling.

"Strike Doubling"
"Single Strike -Flat Field Doubling" (a form of "Strike Doubling")
"Double Strike - Flat Field Doubling"
"Ejection Doubling"
"Boucing die"
"ETC...."

[Bill in Burl]

Yes mechanical and machine doubling are 2 ways to say the same thing. Here's a link that has some links to other types of "not-die doubling". MD is when the die is a little loose in the keepers and slightly moves as the die is coming up just after making the strike .. you get a small mirror image as the die is rising from the planchet.
http://doubleddie.com/144801.html