Like many of you I tried the 22LR AR conversion kits but found they have a few drawbacks: the diameter of the 22LR bullet in a 5.56 chambered AR leaves something to be desired in the accuracy department, reliability is spotty depending on the rifle/ammo, and if you fire enough rounds through your converted AR the gas tube can become somewhat clogged (a couple 5.56 rounds quickly rectifies the problem but just noting it for those that may be unaware).
Due to the reasons above, I started my search for a dedicated 22LR upper but found that most were pretty close in price to some of the dedicated 22LR ARs on the market. So rather than just having a dedicated upper, I just went for it and got the M&P 15-22. I've been glad I did ever since.
Here's a quick run-down of the pros/cons of the rifle:
-All controls function just like the AR platform making weapon manipulation drills realistic
-Comes with a 25 round mag that's easy to load. Spare mags are reasonably priced ($20-25 most places)
-Stock and grip are interchangeable with common AR accessories if you want to swap them out
-Has been 100% reliable with the recommended ammo
-Is more accurate than conversion kits
-Comes standard with a polymer 1913 rail for adding accessories
-Good sights; rear sight is dual aperture
-Uses a proven operating design (very similar in function to the 22/45 pistols by Ruger)
-Cost. The rifle can be had for under $400 most places and every 500 rounds you're saving over $100 in ammo cost vs the 223/5.56 platform
-Barrel is made of carbon steel
-Weight. The rifle weighs 5.5lbs
-Has a case deflector to keep brass out of the face of left handed shooters
-Cost. I know it was a pro as well but buying a complete gun for around $400 is still more than a $120-150 conversion kit would be
-The upper/lower aren't interchangeable with other mil-spec AR uppers/lowers. I don't think it's a big deal but more versatility is better than less in my opinion
-While the polymer seems durable thus far, it's still polymer not aluminum/steel
Here's a video of my wife and I running a few rounds thought it followed by a demonstration of disassembly/assembly procedures and a discussion of the pros/cons of the rifle:
In summary, this gun is a winner for Smith & Wesson. Compared to its' competitors it's a more realistic training rifle for the AR platform that performs well in all areas. Reliability is great, cleaning is a breeze, and new shooters will love this rifle.