I'm darned if I ever noticed any difference in accuracy in any of the model 70's or model 54's I've owned in my life in terms of fore arm screws. I intend to try leaving the screw out though on the next range session, again, and see. But I'm not expecting world shattering results. After this, I'm off to worrying about other stuff.

"You can lead a man to logic, but you cannot make him think." Joe Harz
"Always certain, often right." Keith McCafferty