Is it necessary to break-in my new M&P 15? If so what is the proper way to do it? Thanks for your help

I'm sure someone has a particular method and a reason for recommending it, but I simply field strip and thoroughly clean a new gun like that, make sure it's lubricated and run a couple of hundred rounds through it, using all the magazines I have for it for at least a few rounds if unable to load each to the maximum to ensure feeding, ejection, site regulation and to see if everything is tight, staked, and screwed on properly from the factory.

If it does what it's supposed to with no bobbles I consider it "broken in" after about 500 rounds total. All semi autos must be properly adjusted and maintained to operate trouble free, but if any inherent problems exist they'll most likely show up in the first 500 rounds if at all. At least that's my 'rule of thumb', and there are always exceptions to every rule, so . . . .

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Qui plantavit curabit

Are you talking about barrel break-in or action break-in? Lots of differing opinion on the former, from "shoot it until you run out of ammo or get tired of the nose and recoil" to 1 shot, clean x 10, 3 shots, clean x 10, or various and sundry permutations of that sort of 'fire-lapping' process. I tend to tilt toward the former myself, but cannot claim any particular expertise.

thanks

Also, avoid the cheap, supposedly "military-spec" ammo with steel cases for the first few hundred rounds.

Instead, use good ol' brass cases from a reputable company that adheres to tight specifications, such as Federal's "low-cost" .223 FMJ you can get at places like Wal-Mart for about $35/100.

The brass cases are more "forgiving," feed-wise and also more gentle on your chamber. They'll smooth and break-in the chamber properly.

After about 500 rounds, THEN run all the cheap metal case stuff you want and it will feed as slick as **** through a goose. And, this is also the right time to test premium hollowpoint ammo to see which rounds your M&P 15 "likes" and shoots best. Your 1 in 9 twist ratio favors the lighter end of the bullet weight types, accuracy-wise. Lots of good stuff to choose from.

And, as always . . . M-16s and AR15s LIKE to run WET! KEEP IT LUBED and you'll keep the gun "happy" and dependable.

Hope you like your new M&P15 as much as I do mine!

T.