My 10/22 works just fine with any rounded type bullet, but fails to feed with Winchester 555 (third from left, below):


The square bullets hang up on the breech face.  Anyone have this problem, and if so, what did you do about it?

In normal times, I'd just go to Wally World and buy something else, but I have three boxes of this.

Ruger or aftermarket magazine?  I just polished off a Winchester 555 brick over the last two weeks and haven't had a single problem.

Aftermarket.

Are you using a BX-25 or the rotary mag?

A lot of semi autos have problems with the Win 555,333,etc and the Xperts because of the wide flat nose.

Even my finicky 10-22's will feed them out of a BX-25 it seems.

Both.  BX-25's are the only extended capacity magazine I'd recommend.  In my opinion, all others are hit or miss as far as operation.  Some guns will run them and some won't.  
There was a guy at the range 2 weeks ago who was having stovepipes every 2 or 3 rounds out of his cheap all-plastic 25rd mag.  I let him borrow my BX-25 and he mag dumped it 3 times without a hitch.  
CDNN usually has the best deals on Ruger 10/22 mags.  They run sales pretty regularly with 10rd box mags for $9.99 ea. and BX-25's for $19.99 and BX-25X2's for $29.99.  

Typically, I run (3) rotary mags on an AlanGator Tri-Mag.  LINK
You can shoot prone or off the bench without the additional mags getting in the way and I've never had one loosen up on me over 1,000's of rounds.  I save the 25's for when I'm walking the fence rows.

Thanks for the info.

CDNN had them for 24.99, but I got two of them from Grabagun for $19.99 apiece plus 5.95 shipping.

I have two plastic Eagle mags that actually work pretty good, but are sensitive to the type of ammo you use. I'll keep them in the rifle case for spares/backups.  Thanks again.

No issues with flat nose rounds here.

Ran the BX-25's this evening.

World of difference. Used the 555's again.  This time, only one failure to feed in about 100 rounds, which could have been because of a low powered round. Otherwise, flawless. No rounds hitting the breech face.

This was the final step in rebuilding my 10/22, which I got in 1998 and hadn't shot for years. Good to have it back!