I picked up this Smith & Wesson M&P10 a week ago and have been putting it together Cash style (1 pc at a time) as the parts arrive.  As of this writing, I am waiting for the final piece, which is an IWC QD sling point to attach in the handguard instead of the rail piece/sling QD combo thingy that MI includes with the handguard.  Let's start with a rundown of the gear:

Rifle:  Smith & Wesson M&P10, .308 Win., 18" 5R lightweight barrel
Handguard:  MI 308 SS freefloat tube handguard, modified with screws drilled and tapped through the handguard and into the barrel nut for better security.
Charging Handle: Factory (it's proprietary) with Badger Gen 2 Latch
Gas Block: MI Low Profile 0.75" Gas Block
Brake:  JP Enterprises "Tactical Compensator" 2.25 x 1
Sights:  KAC 99051 folding front, Matech folding rear
Light/mount:  Gear Sector 6P mount, Surefire G2X
Optics:  Trijicon TA11HG ACOG in Larue mount
Buttstock:  B5 Gen 1 Sopmod w/Gear Sector QD sling attachment
Grip:  BCM Gunfighter Mod1
Trigger:  Geissele SSA-E

**One modification I want to be sure and mention is the replacement of the ejection port cover rod.  Some may not know that there are two lengths of this rod.  The standard AR10 rod and the AR10T rod, which is 1/8" longer.  When changing from the delta ring assembly to a freefloat handguard, you need the longer AR10T rod.  Otherwise, the standard rod will walk forward under recoil and out of its recess in the receiver under the deflector.  I got mine directly from Armalite.

The idea behind this configuration is to be a general purpose outside rifle for hunting deer and other large game in the Southeast US as well as being available to provide fast and accurate fire if needed from 50-800 yds.  Some of the options above are self-explanatory.  I chose the compensator because the factory muzzle device is like 3.5" long, and not terribly effective.  I figured at .308 is loud anyway, I may as well gain the advantage of faster follow-up shots and being able to spot my own shots.  The JP Brake accomplishes this.  The ACOG is the fall-out of a very long journey I made through most of the popular Low-medium powered AR optics.  There's a thread on here you can search for and read if you want to know more about that.  I don't want this to be a precision rifle necessarily, but I do want some magnification and the ability to compensate for bullet drop at ranges.  The ACOG does that, all while being rugged, lightweight, compact, having bright and clear glass, and an illuminated reticle.

Now, before getting into this rifle, I read as much as I could online about it and honestly was disappointed at how little good info there was about it.  Hence, my hope in starting this thread is that info is shared and those interested can ask questions and gain insight into a future purchase.  I had read about this rifle being "MOA accurate."  Well, without pics to prove it, we all know that MOA gets stretched a lot.  So, I went and bought a box of Federal Gold Medal 168gr .308 from the local gun shop and mounted a Zeiss 3-9x40 (the highest magnification scope I own) scope on the rifle to give it the best chance to show what it could do.  The procedure was to setup a target at 100yds.  I planned to fire 4 consecutive 5-shot groups at 100yds to capture the effects of the barrel heating, etc.  First, though, I had to confirm that the scope was going to hit what I was aiming at, so I fired 7 rounds of PMC 147gr at a 2" aiming dot below the actual target to confirm that the scope was close.  So, technically, I suppose I began the test with a somewhat "hot" barrel and got it hotter as the test went on.  

I loaded a 20 round PMAG with the 20 rounds of Federal 168gr and got prone in the bed of my truck with the forend resting on my hunting pack.  The rear of the stock was supported by a sandbag.  I will post the pictures of the groups below in chronological firing order (first through fourth).  I made a slight windage adjustment after firing the first group, and you'll note it below.  I fired at a rate of roughly 1 round every 3-4 seconds.  I do wish I had a higher power scope for the accuracy test, though.  While the Zeiss is a wonderfully clear hunting scope, the crosshairs are a bit thick and 9X is a little shy, so I couldn't really see where on the red dot I was aiming because the crosshairs covered the whole thing.  Even so, I think the rifle did well.  The Good Lord saw fit to bless us with rain yesterday, so I got to fire the groups in a steady drizzle.  So here are the groups:


M&P10 grp 1 by ASH556, on Flickr

M&P10 grp 2 by ASH556, on Flickr

M&P10 grp 3 by ASH556, on Flickr

M&P10 grp 4 by ASH556, on Flickr

Untitled by ASH556, on Flickr

Untitled by ASH556, on Flickr

I find it interesting to note that the last group fired was the best because at that point the barrel was good and hot.  I think I had probably just settled into the best position and firing rhythm.  It does speak very well of the barrel, though, that even with heat the POI doesn't shift and the shots aren't stringing.  When I was looking at getting this rifle, I laid out a 1.5-2MOA accuracy criteria.  This rifle beats that easily.  Now, with the ACOG, based on some shots I fired while zeroing it with my Federal 150gr Fusion hunting load, 2" is the best I could do, so my hunting combo (rifle, optic, ammo) is a 2MOA combo.  Still works for me!  

As of yesterday, I have fired 73 rounds through the rifle.  I have had two malfunctions.  Both were with 147gr PMC, which I suspect is loaded to Nato pressure (box is labeled 7.62x51).  The first was a failure to lock back on an empty magazine and the second was a failure to feed where the spent round was fired and ejected, but the bolt partially closed on the round, about halfway up the brass with the primer end of the round still down in the magazine.  Both of these were after I had fired the 20 rounds of match ammo and so the rifle was dirty.  The combination of a dirty chamber, rain, lack of lube (I initially lubed the rifle with Slip 2000 a week prior to this range session when I first got it and had not added any since), and low-powered ammo are to blame for the 2 issues...not the rifle.

Overall the rifle feels to me about like an 18" AR15.  It's really trim and pretty lightweight.  Completely different from handling an LMT or a KAC, which could not be mistaken for an AR15.  Also, there's no denying that the price point of the M&P10 makes it attractive.

Here are a few pics of the rifle in its final configuration.  You'll note the ARD removed from the ACOG in some of the pics...that stupid thing is now a permanent resident of my workbench.  The little honeycombs hold water like you wouldn't believe and I very quickly couldn't see through the optic anymore....remove the ARD, problem solved.  To me, that's a critical issue and since I'm much more likely to encounter rain than a countersniper who sees the glare off my objective lens...the ARD stays off.


Untitled by ASH556, on Flickr

Untitled by ASH556, on Flickr

Untitled by ASH556, on Flickr

Untitled by ASH556, on Flickr

Very Nice!

JP brake?

Thanks!  Yup:

Brake: JP Enterprises "Tactical Compensator" 2.25 x 1

I bet if you have a better rest it will do a lot better. Mine puts the Federal GMM in the same hole ;)

I can't express how jealous I am...just know it's a lot.