Barrel Twist:1 in 8 or 9?

I've looked to 4 different dealers. They all have the S&W M&P Sport with the 1-9" twist only. This is an entirely different barrel than the 5R- 1-18" twist barrel. They both have the same SKU#: 811037. Is there any way of getting a 5R-1-18" barrel in the Sport?
Thanks, Rich Hayes
 
I've looked to 4 different dealers. They all have the S&W M&P Sport with the 1-9" twist only. This is an entirely different barrel than the 5R- 1-18" twist barrel. They both have the same SKU#: 811037. Is there any way of getting a 5R-1-18" barrel in the Sport?
Thanks, Rich Hayes

Find one used. You probably mean 1-8".
 
I've looked to 4 different dealers. They all have the S&W M&P Sport with the 1-9" twist only. This is an entirely different barrel than the 5R- 1-18" twist barrel. They both have the same SKU#: 811037. Is there any way of getting a 5R-1-18" barrel in the Sport?
Thanks, Rich Hayes

Hi Rich,

You resurrected an old thread. S&W changed the barrel spec of the 15-Sport from the 1:8 5R barrel to a standard 1:9. The only way to get a 15-Sport with a 1:8 5R barrel is to buy a used 15-Sport or find "new" old stock.

When you search the forum, you'll see that we like to debate the technical and theoretical superiority of the 1:8 5R barrel. I own AR-15's with both the 1:8 5R and a 1:9 barrel. For range plinking and out to 100 yards using commonly found factory "practice" ammo, I have not seen any practical difference between the two barrels.
 
What John said! If you're loading 55gr already, 1/9 is plenty good.

Good Luck and good shooting. :D
 
Probably 90% or more of the .233/5.56 shooters never load 77-gr or heavier. If you are one of those, then the 9-inch twist is actually a better alternative (probably).

I thought it interesting that the recent review in The American Rifleman noted batter accuracy with the Army's new 5.56 ammunition from a 9" twist barrel than from the 7-inch. That particular load has a very long bullet, but apparently the 9-inch twist barrel did the job - at least at the ranges they tested.

I fully realize that comparing results from only two barrels, particularly with no history of the quality of either, is a bit opening a can of worms, but I wouldn't be afraid to buy one of the new Sports with the 9-inch twist for anything up to and including the 69-gr BTHP target loads.
 
Thank you all for your input. It all shaped my opinion on the matter. Yes, to my first response, I did mean 1-8" 5R barrel. Anyhow, I am unhappy that S&W uses the same SKU# for the 1-8" 5R barrel as they do to the 1-9" 6 groove barrel. There is no way to differentiate the two; neither of them have the barrel specs on the box. One would have to physically examine each one to determine which is which.
Thanks,
Rich Hayes
 
...I am unhappy that S&W uses the same SKU# for the 1-8" 5R barrel as they do to the 1-9" 6 groove barrel. There is no way to differentiate the two; neither of them have the barrel specs on the box. One would have to physically examine each one to determine which is which.
Thanks,
Rich Hayes

Don't start looking at the 15T's then lol. Several running changes on that model as well.
 
Thank you all for your input. It all shaped my opinion on the matter. Yes, to my first response, I did mean 1-8" 5R barrel. Anyhow, I am unhappy that S&W uses the same SKU# for the 1-8" 5R barrel as they do to the 1-9" 6 groove barrel. There is no way to differentiate the two; neither of them have the barrel specs on the box. One would have to physically examine each one to determine which is which.
Thanks,
Rich Hayes

Hi Rich,

As John mentioned, S&W changed the twist spec on the Sport. About a year ago I started considering purchasing a Sport. From what I was able to tell then, S&W phased in the 1:9 barrel during the spring of 2013 when ARs were in hot demand. I suspect the initial spec change may have been an effort to produce as many Sports as possible as the 1:9 is a more common twist rate. The sku is the same because all new Sports now are shipped with the 1:9 barrel and have been since mid 2013.

I bought a 1:9 Sport in October 2013 and am very pleased with its accuracy with 55 and 62gr. Most common commercial ammo is either 55 or 62 grain anyway. That range of grain weight seems to be the the 1:9 sweet spot, not taking into account other bullet variables that affect accuracy such as length.

I'll offer this regarding twist and the Sport barrel: my personal opinion is that the heavy barrel on the Sport is what makes the Sport an accurate rifle with 50-70 grain bullets rather than a one inch difference in twist. Before I bought my Sport I had a retro AR made from late 1970s M16A1 parts with a new pencil profile 1:9 barrel. That rifle was not accurate. My opinion is the thinner pencil profile was affected more by heat and stress from using a sling for support. From my experience the 16" 1:9 heavy barrel on the Sport is very accurate when you use 50-70 grain bullets and do your part.
 
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I'm going to order am M&P15, and notice some models have a 1 in 8 inch twist, while some have a 1 in 9. Gun will be mainly for recreational fun. Any thoughts on what twist rate is best? I handload everything, 223 usually 55 gr FMJ with H335 performs great in a Mini 14 (stop snickering, I actually like the gun).

Won't find any snickering on my part.

I'd rate my Mini and AR #1A and #1B. Both handle their jobs well... and that Mini will eat any ammo, chew it up, spit it out... never jams... and it takes nothing more than a 1/4" punch to tear it down.

Just ignore them. If they hate on it, it just shows ignorance.

BTW... I load 25gr w748, 55gr Xtreme FMJ. Runs excellent thru both guns.

Oops... on the old thread. At least I didn't resurrect this one. :D
 

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I like the mini 14. It's a fun little gun to shoot!

Ditto. I have a 581 series Mini-14 and really like it. I find it to be very accurate out to 300 yards and "hunting accurate" out to 500 yards. Quite a few Coyotes would testify to that ........ if they could.

Bob
 
I've owned both 1:8 and 1:9 sports. I second JaPes...there's zero practical accuracy difference between the two. To be honest, my 1:9 is a better shooter. But that's just because I upgraded the miserable stock trigger to a Geissele.

I'd take whatever sport I could find the cheapest and have fun with it. :)
 
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