I load 200 grain LSWC almost exclusively. (Mainly because I cast them myslef so my loaded round price is about $45 per 1k
I run mine at a length from 1.23 to 1.25 diferance in function, and accuracy is indistiquishabele. I found that properly taper crimping eliminated the problem of failure to eturn to battery.
On a side note it could be from limp wristing.
My M&P has only jammed once a friend was shooting and limpwristed badly and it jammed after a few rounds with him shooting. Has not done it with anyone else shooting since.