"what is the point of firing 100 rounds, for example,
from the R9 in a single session?"
I guess I could have shot 2 or 3 rounds and gone home.
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The point was this: It was a new to me used gun and I wanted to see if it would work and work when it was dirty. It was and it did. And I like to shoot. That's why I shot the BHP, the P-32, the 442 and Winchester SX-1 shotgun after I finished with the R9. It's a shame I was on a tight schedule that day.
"There is a limit where no proficiency is achieved beyond a certain amount, no matter what the hand strength."
There is? Got any proof? And there's more to it than hand strength, there are major muscle groups to be conditioned and trained in the shoulders, torso, hips and legs. Feet too I suppose, and dry firing just won't do it all. And practicing mental focus is of the utmost importance.
I've been shooting for every bit of 50 years and haven't seen any proof of your assertion. As long as I can maintain my form and hit the target I'm having fun and practicing. If I can't maintain my form I'd just be blasting and wasting ammo to make some noise - I call it recoil therapy for those who like to do it.
Sorry if me shooting my gun upset or confused you somehow.
John