Stormin Mormon writes:

Mighta worked on rubber AC hoses, but I doubt it will do
much good on copper.

A 1/16" hole in a 300 psi line requires less than a pound of force to seal.
well within the capabilities of a scrap of rubber convered with a hose
clamp.

Another technique is to whip with copper wire and then solder.

Analysis and improvisation work when the "correct" stuff isn't at hand, or
too costly, often better. Many factory parts are cost-reduced to bare
minimum performance for the task, and you can cobble up something stronger
than the original.