jsimmons, I did think of that but if I build a varminter, I still want a shorter M4 style also so it's kind of 6 of one half a dozen of the other for me. I'm only planning on shooting on the range out to 500-600 yards so I would think the 16" barrel should be able to handle that alright for now.
Must be nice to have a range that has a 600-yard position...
I happen to agree with you. The S&W Sport is a fine platform, and since the Sport is just another AR-15, you can do anything you want to it to make it more appropriate for the intended mission. I have a M&P15 MOE that has gone through a lot of changes itself:
- UPG-16 pistol grip (it's got replaceable forestraps and backstraps so you can implement the best configure for you (I personally hate the hard plastic MOE and standard AR-15 grips). ($30)
- M16 BCG ($110) with Sprinco Blue action spring ($23) and H2 buffer ($36)
- Primary Weapon Systems Enhanced (extruded) buffer tube ($65)
- Smith Vortex G6A2 flash suppressor (the best suppressor I've ever seen) ($50)
- Magpul CTR Stock - to get the QD sling swivel hole ($75)
- Troy folding rear sight - the Magpul sight was plastic, and it just looked/felt cheap to me ($90)
- Yankee-Hill folding front sight/gas block - I don't care for the standard FSP, and even though the fornt sight would not have been visible in a magnified optic, it would still have prevented the maximum light transmission the scope is capable of. ($65)
- Jard non-adjustable trigger ($115)
On top of the $1100 I paid for the rifle, I've spent an additional $650 on upgrades (not counting shipping, or buying parts that it turned out I didn't like). I still haven't changed the barrel/hand guard (another $600, give or take), which I really want to do.
It would have cost me less to just build a rifle from scratch the way I wanted it, which I subsequently did. I paid about $1300 (not counting shipping charges for the parts) for a rifle with all the "right" parts already in/on it.
So, if you're going to buy a Sport, consider the following changes :
0) Change the barrel to a 16-inch mid-length 1:8 or 1:7 barrel. This will keep the action from being chewed up as a result of being over-gassed (as is typically the case in a carbine-length system). This will also require changing the hand guard and the gas tube. I use BlackHole Weaponry barrels at $250 each, and my homemade AR uses one of their 16-inch stainless 1:8 mid-length barrels.
1) Use a floating hand guard to avoid barrel deflection caused by grip and/or sling use. You can actually do this without changing the barrel, but when you do get around to changing the barrel, you'll have to do it again if you change to the mid-length gas system. I would recommend getting one with a full top rail and the ability to bolt on additional rails as needed on the sides/bottom.
2) Change the trigger to one of the high-quality triggers available. You can spend as little as $65 for an ALG ACT trigger (made by Giessele), to as much as $300 for a Timney or a fancier Giessele, with a lot of choices in between. I use Jard witha full-power hammer spring because it's a smooth single action trigger with a 4.5 pound pull, it's reasonably priced, and it's not a "match" trigger.
3) To lessen the recoil pulse, change the BCG to a M16 BCG, and use a quality action spring with the heaviest buffer you can find that still allows the action to cycle properly. Reducing the recoli pulse allows you to better keep the weapon aimed at the intended target. I use the M16 BCG from Spike's without any special coating, Sprinco action springs, and a standard H2 recoil buffer.
4) Change the front sight post to a folding front sight. I use the yankee hill gasblock/folding sight because I don't think optics or sights should be mounted on a handguard. If they're mounted on the barrel, then the bullet will go where the barrel is pointed.
5) Whatever you do, stay away from anti-rotation pins. The only thing they do is make the trigger harder to pull. I used to have them on my ARs, but took them off due to increased trigger stiffness.
Keep in mind this is one man's opinion and for every person you ask, they will provided a different one.