Dont think many people know about this product so thought id share. Nic Taylor makes replacement followers and mag springs for many .22 pistols. I bought some for both the M&P22 and 22c pistols. 22 now has 15 rounds and the 22c now can hold 14. you will lose the load assist button which also functions as the hold open on last round activation. no biggy to me in a plinker pistol. ive been using a .22 Lula that works pretty well. ive ran at least a brick thru each gun with these new internals with no issues.

they run $12.99 plus shipping.

videos and purchase

I can't imagine giving up the load assist button to get 4 more rounds in my c version. I'ts just too much of a bitch to load that way especially if you're firing a couple of hundred rounds at a crack.

I'll wait for a real extended magazine. It's only a matter of time

I bought one of these kits a couple of weeks ago for my 22c, wanted to try it in one of the 2 mags I have, it is very difficult to load and I only use that magazine in the little M&P when I keep it in my truck for self defense as in that case the extra 4 rounds could come in handy, no way would you want to try and load this 14-round clip at the range or for plinking, other than that though the clip feeds well and works just fine with the modification and can be changed back to stock in about a minute.
I too am looking forward for the factory extended clips

Under perhaps a different circumstance I would be all about more rounds ... but I was just thinking the last shooting session about how I always use the load assist button, and how easy the M&P22C mags are to load compared to other magazines (I have 8 mags for the 15-22 and they're all 10-round mags with the block tapped out because I moved to FL- they're impossible to load in any decent time w/o using an improvised helper - I use my John Deere Gator key inserted through the follower-block hole, to press down each time I load a round, much much simpler. Otherwise it takes 15 minutes to load the mags and 15 seconds to shoot them...) - even compared to my Remington and Savage rimfires, centerfire pistols, etc.

I also think the last round hold-open is a big feature, not necessarily an absolute must but, losing the load assist button AND the hold-open for 4 more rounds is not a bargain IMHO.

I will also wait until 10-rd mags become cheaper and therefore easier/more plentiful and/or extended mags become available. But thank you very much for sharing this option, which no doubt will be adopted by people gratefully on this board.

I'm waiting for S&W to start shipping the new 30 round M&P 22C mags.