I was glad to see this thread resurrected. I just purchased a PC Shield 2.0 45, 4" barrel. I was so stoked to get it, and after the first round was fired, the slide locked and the following round failed to load. I ejected it by racking the slide. Fired another round, and the same thing. This went on through the first 2 mags. I've never had a problem with any of my S&W guns, and Shield 9 has been flawless.
I was reading up on this thread, others, and looking on youtube and apparently this is a problem. Ugh.
I tried a thorough cleaning and oiling, including both factory mags (which are the newer version), and still getting the same issues with all types of ammo.
THe rounds seem to be hanging up, and I noticed on a couple of them that the side of the casing was scratched, like the ramp may be catching on the round as it leaves the magazine and before it loads into the barrel.
Any additional suggestions are welcome but it looks like my new shield is going back to SW for a repair.
The Shield 45 has precious little room inside the magazine well between the tip of the bullet and the feed ramp. With my 45, I've discovered that the cartridges must be fully seated to the back of the magazine. If they are allowed to protrude even slightly from the rearmost position, they can catch on the feed ramp, and create the jam you've described. When I load my cartridges, (I use an Uplula loader, BTW), I make sure they're fully seated by feeling for a slight "click". The click coincides with the inability to push the cartridge any further into the magazine. Try this and see if it cuts down on your mis-feeds.
I also hand polish the upper and lower feed ramps with a
mild car polish each time I clean my 45. I apply with a Q-tip, and buff with a cleaning patch. I don't know how much this helps, but the ramps are nice and slick when I finish, so it couldn't hurt.
You said the problem occurs with different types of ammo, so I'll assume out-of-spec ammo can be ruled out.
Another possibility is that the upper and lower feed ramps are misaligned. They should form one continuous surface. You can check for this with your slide locked back. If the upper ramp is protruding or recessed in relation to the lower ramp, that could be the source of your problem. That will require a trip back to the factory to fix.
A remote possibility is that you have a burr on back of your magazine well that is pushing your magazine too far forward. So check your well visually and by feel. That's probably a factory repair, too, unless you're really handy with a Dremel.
Don't give up on your Shield 45. S&W has very good customer service and will work with you to make it right. I've had mine over three years and have put 7,600 rounds through it. It has been very reliable and amazingly accurate, so it's a keeper. Good Luck!