M&P Sport II and Accuracy

[TechJunkie]

I am looking at the M&P Sport II and the Ruger AR556. My purpose for the AR will be home defense and Coyote hunting. I have spent days and days comparing the two. I have one question holding me back from pulling the trigger.

After researching both guns the M&P Sport II is in front for several reasons. The issue holding me back is the accuracy difference (if any) between 100 and 300 yards with the 1:9 Sport II barrel and the 1:8 AR556 barrel. I can't seem to find any real world comparisons with accuracy and distance shooting for varmint hunting. I shot a few rounds out of an AR556 but didn't have any optics to test at distance. I am not expecting either AR to cover a nickel at these distances. I don't expect to shoot 70+grain loads. I just would like a comparison of these two guns or twists at distances I might shoot for coyote hunting. I am interested in knowing if the 1:9 M&P can shoot comparable groups to the AR556 1:8 when a satisfactory round is used. I am concerned whether the M&P groups will open up more than the AR556 groups at 200 and 300 yards due to the difference in the twist rate. My brother-in-law says I am overthinking this, which he may be right. His contention is that for the rounds I would most likely be shooting, 45 - 69 grain, there will not be a noticeable difference between the two twist rates. I cannot use an AR in 556 or 223 for deer hunting in my state so I would never envision needing a heavier bullet. I thought I would ask here as you guys seem very knowledgeable.

If not for the twist rate and accuracy at distance question I would already own the Sport II. I have had great success with Smith & Wesson firearms and I don't expect less from the Sport.

For the record I have other rifles. The decision on getting an AR is for home defense and to be able to coyote hunt with it. I consider my 22/250 an heirloom and enjoy shooting it. It is a tack driver, however, it is not a gun I want to beat through the woods, rain or mud.

Thank you for any input provided.

 

[TAC]

You can't go wrong with either. You'd probably be hard pressed to be able to tell a difference between the two. You'd likely need to spend about twice a much, to buy something that would be noticeably more accurate.

You'll possibly want to purchase an after market trigger.

 

[cyphertext]

Your brother in law is right... there is more to accuracy than just twist rate.

Either one is capable to fulfill the role you want it for.

However, since you mention hunting and accuracy, it sounds like to me that you would want to free float the barrel and change triggers. If you are wanting to free float it, I would suggest that you go with a rifle closer to how you want it really set up, or purchase a OEM rifle with a low profile gas block already installed so that you could add the free float hand guard of your choice.

 

[Win94ae]

Twist has nothing to do with precision at distance; either your bullet is stabilized, or it isn't.
The difference in twist rates, has to do with stabilizing specific length bullets.
Your brother in law is correct.

 

[TechJunkie]

Thank you for the replies. It will mostly be a home defense and fun target gun. Coyote hunting will be done but not as avidly as we deer hunt.

I do tend to over analyze things and I am aware of that. I realize that there are many variables and it is difficult to provide a definitive answer. I am hoping to find someone who has shot both guns and can speak to their relative accuracy. I know that the guy behind the trigger often has the biggest effect on accuracy. Given that, however, if a competent marksman shoots both guns they are able to identify which one provides the best groups at a specific distances and when one gun starts to open up given a specific grain round.

If all 1:9 and 1:8 refers to is the weights of bullets the AR can stabilize well then my question would be does the Sport II stabilize 55 grain rounds at 200 yards comparable to the AR556? I know that the faster spin can keep a bullet stabilized longer, though at the yardages I am interested in the two twists rates may not show appreciable differences. I hope I am making sense and not just running in circles.

I never had issues with this before as my 22/250 and 270 were gifted to me and were proven tack drivers. This is my first foray into making the purchase myself and out of these two guns I want to make the best choice possible. As I said, all things equal, I would already have the Sport II. If the Sport II can comparably shoot out to 200 yards with 50 - 55 grain rounds and group comparably to what the AR556 could then my decision is made.

 

[TechJunkie]

Twist has nothing to do with precision at distance; either your bullet is stabilized, or it isn't.
The difference in twist rates, has to do with stabilizing specific length bullets.
Your brother in law is correct.

I appreciate your reply. My question centers around the 1:9 Sport II keeping a 50-55 grain round stabilized out to 200 to 300 yards. If at this range stability is not an issue with the 1:9 twist then I would expect the Sport II to pattern similarly to the 1:8 AR556. Is this what you are saying as well?

 

[Racer X]

When you look at other calibers, there usually aren't a wide range of twists, and a wide range of bullet weights. Take .22 LR rimfire. Most bullets produced are either 36 or 40 grain. I am reasonably sure there is just one twist rate traditionally used.

With .223 or 5.56 you have bullets from 40 grains to about 90 now. And 4 to 6 commonly used twist rates. Lots of variables.

 

[cyphertext]

I appreciate your reply. My question centers around the 1:9 Sport II keeping a 50-55 grain round stabilized out to 200 to 300 yards. If at this range stability is not an issue with the 1:9 twist then I would expect the Sport II to pattern similarly to the 1:8 AR556. Is this what you are saying as well?

The 1:9 twist is the optimal twist rate for 55 gr. If you are going to shoot 55 gr and 62 gr rounds, you will not see any benefit to the 1:8 twist. If you are going to shoot longer projectiles than typical of the 55-62 gr range, you may see some advantage.

However, each individual barrel is different. I could tell you that my 1:9 twist AR is more accurate than my 1:8 twist AR... but a sample of one is meaningless.

 

[Moe Mentum]

Go with the M&P Sport, most of us have, you will not be disappointed.

 

[otisrush]

I appreciate your reply. My question centers around the 1:9 Sport II keeping a 50-55 grain round stabilized out to 200 to 300 yards. If at this range stability is not an issue with the 1:9 twist then I would expect the Sport II to pattern similarly to the 1:8 AR556. Is this what you are saying as well?

Well, I haven't done any formal or detailed testing as to your question but.....

I have a Sport I and I frequently ping steel gongs at our range in the 400 yd distance with 55 gr FMJs (reloads). I've never put paper out at that distance. And I don't hit the steel EVERY shot....but most shots. (Sorry - I don't know how big the plates are at that distance....they're on the order of 12"x12". I would guess.) And those are FMJs. I have a match grade 53 gr bullet I load (Hornady) that gives me 1" groups at 100 yds. I don't know how those do at longer distances.

 

[Rastoff]

If I'm not mistaken, the 1:9 twist rate was picked by the military specifically to stabilize the 55 grain bullet. There just isn't enough difference between the two rates to make a significant difference. Of course you've already been told that.

Neither of these guns is a precision tool. You should expect about 1.5MOA accuracy. The military expects them to be effective out to 500 meters. That's a 4.5" group at 300 yards. The USAF uses a 300 meter zero. The Marines practice at 500 meters with iron sights.

The one big difference is the warranty. I'm sure the Ruger has a good warranty, but S&W customer service has a proven track record. I'd pick the M&P if only for that reason.

 

[hdwhit]

Techjunkie wrote:
If all 1:9 and 1:8 refers to is the weights of bullets the AR can stabilize well then my question would be does the Sport II stabilize 55 grain rounds at 200 yards comparable to the AR556?

For bullets of 60/62 grains and below, the difference in stability between 1:9 and 1:8 will be insignificant. See this article for more detail: How to Pair Barrel Twist Rates with Bullets - Guns & Ammo

If you are going to be shooting 55 grain bullets and plan to slavishly follow twist rates in your selection process, then you will note that the article points out that 1:8 barrels can spin 55 grain bullets too fast, so your choice of the S&W would become academic.

 

[TechJunkie]

Thank you!

I want to thank everyone for the great replies. I appreciate you spending the time to answer my question.

To the point, I did buy an AR but I decided after considering what I wanted to change or add I should probably consider looking at other ARs as well. I know this may be somewhat controversial to some but I decided to purchase a Springfield Saint. I know it doesn't have the proven track record of the Sport II as it is a new offering, however, it came setup with some of the things I would have changed on the Sport and I liked the mid level gas system and the trigger is amazing. I also really like the BCM Tupperware which I like and won't change. There are some other things I liked about the Saint but they are probably nitpicking by comparing. Time will tell if I made the right decision but from my initial impressions and from my two outings shooting it I am pleased which is I guess what counts.

Thanks again!

 

[cyphertext]

I decided to purchase a Springfield Saint.

Give us a range report please! (just not in this forum)

 

[TechJunkie]

Give us a range report please! (just not in this forum)

Any one interested can PM me. I would be glad to share my impressions.

 

[arnoob]

Any one interested can PM me. I would be glad to share my impressions.

I'd be interested to hear your thoughts too, I don't think it would be OT to just post a short review in the thread.

 

[cyphertext]

I'd be interested to hear your thoughts too, I don't think it would be OT to just post a short review in the thread.

Phil has been cracking down on things that are not M&P 15 related, so any review of the Saint should go in the "Firearms & Knives - Other Brands" section.

 

[arnoob]

Fair enough.

 

[danet827]

Just my 2 cents

I can’t speak for the AR556, but my M&P 15 Sport ll can shoot 1 to 1-1/8 inch groups at 100 yards with the Monarch 55gr soft point and I can’t imagine the groups would open up to much at 200 and 300 yards, I think the big thing shooting at those ranges would be getting good with the stock trigger or upgrading it, and getting good at adjusting for the wind if you want to shoot lighter bullets. I have never shot anything heavier than the 55gr so I don’t know how good the heavier bullets group. And as far as the home defense aspect, both rifles are very reliable and would make a great choice for home defense. I don’t really think you could go wrong with either rifle though. I chose the M&P because the gun store had it on sale for $490

 

[Xrtaco]

Hey, instead of figuring if a gun is sub MOA off a benchrest, why don't you do 10 push-ups and 10 burbees and then try to shoot off hand at a moving Target at 50 yards. Try that with pajamas on too.

What pains me is that you think you'll be calm and shoot from a rest right after you hear your windows crack open. Be realistic and train your body to react right under stress. I don't care but how well your gun is or how accurate, just wanna know if you'll hit the target.

Don't follow all the hubbub about sub MOA or all that. The rifle is only as effective as its operator.