not accustomed to DA only, so only making bad, wild guesses here
(old Fuff may come along, and will know better questions to ask)
it does look a little like front of cylinder edge has more drag scuffing that I would think ok
suggesting that cylinder front edge is/was scuffing against top strap "gunk" (hardened residue), can be built up and not real noticeable
(yeah, I know, you looked, but if ejector rod was "bent" from some fool wrist slapping it shut, something like, I would not think it would run good for six or seven dozen rounds)
understand feels like good cylinder lock up, but not talking wobble, talking front/rear movement, push cylinder forward w/ thumb, push it rearward... expect to feel a little give when pushed rearward... if no feeler gauges, both ways, look for daylight (got to hold it just right against bright lighting), should always see "daylight" between front of cylinder and forcing cone... always
got a k-17 "especially good" (minimal cylinder cone gap) that will start cylinder drag (evident if look close enough), around 100 rounds, cone drag marks on cylinder face in/on powder residue... but no scuff on a clean face, ever... and smooth as a baby's butt when clean(ed), and spooky accurate.. and all it takes is a quick wipe w/ CLP.. just never saw one that tight in centerfire (beyond my meager means)
internal stuff, you need chat w/ old Fuff
(I don't know enough to guess why will run good for near 100 rounds before such signs)
do check your ejector rod is screwed ALL the way in.. (tightens opposite of a bolt thread, best I recall)... if this is a one/first range trip thing, rather than repetitive, and ceases when well cleaned...
cylinder drag IF that is it, feels a lot like turning a gear reducer w/ hand on output shaft instead of on input shaft
but I am saying far more than I know, here
old Fuff can help !
apologies in advance for false leads
PS
is this repetitive, or a one time 1st run ??