Markings on the barrel of a rifle?

Question

I own a Colt AR-15 and at the end of the barrel , by the sights there is a marking that says 1 - 7 twist. what does that mean and does it have any relation to the operation of the rifle. Do I need to do anything different in shooting or cleaning and does it help the performance.

Answer 1

it is the spin ratio. 1 twist every 7 inches. it really has no relation with the mechanics of the rifle but it does have some relation with the operation. the type of bullet fired is what gets you the performance. I have a ar15 colt hbar and it seems to fire the remington the best. as for cleaning no effect. claen like any other gun run the rod and patch the same direction the bullet travels ALWAYS

Answer 2

1:7 twist is indicative of the rifling of the barrel.  This means that the bullet must travel 7 inches to do one full rotation.    With a 1:7 twist rate, I'd recommend shooting 70-80 grain ammunition for maximum accuracy...any imperfections that occur in lower grain ammo will be amplified by the extra velocity and lead to poor groupings.

Answer 3

it has to do with the rifling in the barrel...it means that every 7 inches that the bullet travels down the barrel the bullet will rotate 1 time....hope this helps.

Answer 4

twists are what make the bullet spin

Answer 5

The twist rate of the rifling relates to the weight range of bullets it'll stabilize. Your fast twist rate is designed to stabilize heavy bullets better than do the slower twist rates. It may over-stabilize lighter bullets. Neither over-stabilization nor under-stabilization is desirable.

Answer 6

This is actualy something that is very important and you should know about.... Look over the below .223 cartridge guide.... Look down at the fifth paragraph and a sensible explanation will be there. This will clearly answer your question.....

http://www.6mmbr.com/223Rem.html

Answer 7

That refers to the lands and groves in the barrel,it has nothing to do with the operation,but its what makes it a accurate rifle,clean the barrel in the direction the bullet travels.Clean it like any other weapon.

Answer 8

That's 1 bullet twist in 7 inches.

It's one of the faster twist rates. I was sure to get the 1/7 rate when I ordered my new upper for the build I am doing right now.

1/7 will allow you to shoot heavier  70 Grain bullets better than a 1/9.

You don't have to do anything different with it. It's a good barrell to have.

Answer 9

1/7 is the barrels twist rate....the grooves inside will cover one full turn for every 7 inches of barrel length.

you will find that your AR is more accurate with mid weight bullets with a 1/7 twist.

You will also find that your AR has the mechanics to deliver more accuracy than your abilty to hold sights on target. That 1/7 twist will wok well.

Have fun!