Ok folks....broke down my DW ECO (9mm) today for a thorough cleaning after a lengthy session last week. I cleaned her up as usual...then when I was cleaning the slide I noticed brass smears inside the slide along the rise that the disconnector head rides along (see pic below). Anyone else ever experience or see this? Looks like when the slide is reciprocating it's riding along the top round of the magazine (or the round being fed) and smearing brass on that part of the slide. I'm a bit perplexed. I didn't see any issues with the gun, except a few times it wouldn't go into battery 100%....a slight push to the rear of the slide with my thumb rectified it.....it also has a new recoil spring so that may need some breaking in a bit... Anyone ever see this type of "brass smear" on the disconnector portion of the slide before?