Don't, but I have one time.
Bought a gun second hand from a guy
that included 4 or 5 plastic boxes of reloads.
First chance I got to shoot I was alone at the
range with the owner that I'd known for a
few years. He sat down by me to watch me
shoot my new/used gun. The first one had
tremendous recoil and a big fireball. The
man said to shoot one more. Samey same
He said let me try one. Samey same.
He advised me to not use any more of that
ammo. I got back and called the previous
owner and loader of the ammo and asked
what was the load he had used. His reply
was " I dunno. . . whatever was maximum
in the book. . . maybe a little more. . ."