Last year I bought a 9mm Taurus 24/7 Pro C DS. Got it home, cleaned the insane amount of packing grease out, and took it to the range. Shot barely acceptable groups, a few stovepipes, but I wasn't used to the trigger and to be honest I don't like lightweight frames. I just wanted a small 9mm and I got it for a great deal.

Took it out again much later, and good god, stovepipe or double feed every other shot. I shot 100rds and gave up. I've never had this many combined malfunctions in my life, than I did this range outing. Took it home, detail stripped the slide. It was already clear of grease from the last time I cleaned it, so I'm like WTF and started to read some interwebs articles.

SOLUTION: For some reason, as well as Taurus designed the gun, they left lots of flashing and burrs on the mag followers and some weird yellow paint on the mag springs. I took some 600grit sandpaper, and smoothed out the body and edges of each follower leg, and wiped the flaking paint off the springs and body.

Just got back from the range - zero malfunctions, smoother feeding, and once I got used to the frame weight, shrank my groups from 7" @ 15yds to 3" @ 15yds. Today was successful.