DaninVA,
My R9s generally ejects the chambered round and loads the next round without incident.
But, if I've just installed a new recoil spring, sometimes the first round hangs up a bit. I attribute that to:
1.) I didn't yank the slide back vigorously enough against the new spring's tension;
2.) My fingers were a little slippery from the lube I applied during reassembly, resulting in 1.)
Generally, I've found that firing a couple of mags thru my gun relaxes the recoil spring enough for a srrong tug on the slide to chamber the next round. For a while there I got in the habit of "exercising" a new recoil spring 20 or 30 times, but gave that practice up when the second generation springs became available.
Steve