The stock was easy. Magpul's https://www.magpul.com/products/moe-sl-carbine-stock-mil-spec/>MOE stock fit the bill perfectly. The comb is wider, which provides a better cheekweld, and it's full adjustable. Although my "work" carbine has a fixed stock, the MOE is the same size and shape so it's a good match.
To attach a different type handguard to the M&P requires using a modified barrel nut. https://www.tacticool22.com/product/free-float-handguard-kit-sw-mp15-22-modified-4-piece/?v=7516fd43adaa/>Tacticalcool22 offers a "Handguard Conversion Kit" that has everything you need. It comes with the barrel nut, which has the proper threads for attaching any free-float handguard. (You can also use it for factory type two-piece handguards.) You get the barrel wrench - a long tube that goes into the stock handguards from the muzzle - to remove the factory nut. The kit also includes the wrench for the new barrel nut and a set of barrel clamps, which are like "real" ones except in miniature.
Removing and replacing the handguard is a simple process. Remove the original nut, using the special wrench, install the replacement nut and you're ready to attach any type handguard. For my clone, I went with PRI's http://www.precisionreflex.com/Products.aspx?CAT=9647/>Gen III Delta. This is the exact handguard on my Katana, with plenty of rails to attach anything you need.
I run fixed sights on my carbines. For the 15-22 rear sight I used the Daniel Defense http://www.brownells.com/rifle-parts/sights/rear-sights/ar-15-a1-5-backup-rear-sight-prod27483.aspx/>A1.5 fixed sight, which attaches to the rail on the receiver. The front sight was a little different. Due to the diameter of the M&P barrel it won't take a standard AR sight base. A little research turned up a company that was modifying standard sight bases to fit 15-22. Again, Tacticalcool has you covered with their https://www.tacticool22.com/product/ar-15-a2-front-sight-sw-15-22/?v=7516fd43adaa/>15-22 sight base. You'll need to pick up the actual sight, spring, detent and other small parts but that's easy enough. After installing the front sight base and small parts I threaded on a three-prong flash hider, again to get the same look as the Katana.
Finally the 15-22 was looking good, but to complete the build I needed a red-dot. Brownells had just what I needed, http://www.brownells.com/optics-mounting/electronic-sights/red-dot-sights/trs-25-red-dot-sight-w-hi-rise-mount-prod79494.aspx/>Bushnell's TRS 25 sight, which has a 3 MOA dot and comes with the mount
The final parts were a http://duckbillgrip.com/>DuckBill Tactical grip, again to match the Katana, and an Agile Sling, which is a simple two point sling with a quick release.
The finished product is almost a perfect match to my work carbine, except it weighs less and it's cheaper to shoot. In other words it's fun. I know what you're thinking – "This is an expensive build." You may not want to go with these same parts. The beauty of the AR is its modular design; with the parts now available the M&P 15-22 is almost the same.
Tiger McKee is director of Shootrite Firearms Academy, located in northern Alabama. He is the author of "The Book of Two Guns" - http://shootrite.org/book/book.html writes for several firearms/tactical publications, and is featured on GunTalk's DVD, "Fighting With The 1911 - http://shootrite.org/dvd/dvd.html McKee's new book, AR-15 Skills and Drills, is available off Shootrite's website: http://shootrite.org/AR15SkillsBook/AR15SkillsBook.html
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