I wouldn't be so sure it's user induced. I had the exact same problem.
I fought it for months, tried other lifters, every ammo you could imagine. No rhyme or reason to it when or if it would lock up. I, and others, threw everything but the kitchen sink at it. I took trigger groups out of 3 different 1301's, and it ran flawlessly with all of them. Now ironically, those other guns ran fine with my trigger group installed too. If you know someone else with a 1301, try their TG and see if you can get it to replicate. Weirdest ghost I ever chased and still really don't understand.
I ended up purchasing an entire new trigger group and that resolved it once and for all.