noob question

[smddb]

I'm new to AR's. My wife bought me a M&P 15T for my birthday and I read that it has a 1 in 8" twist for the barrel. Whats the difference between a 1 in 8 twist and a 1 in 9 twist ? does it mean I can only shoot a certain weighted ammo ?

 

[RGPM1A]

The 1:8 is just a little faster twist rate. Twist rate is just how fast the barrel will spin the bullet before it leaves the muzzle of the rifle. You should be good to go shooting anything from 55 to 75 grain bullets.

 

[smddb]

The 1:8 is just a little faster twist rate. Twist rate is just how fast the barrel will spin the bullet before it leaves the muzzle of the rifle. You should be good to go shooting anything from 55 to 75 grain bullets.

Thank you.

 

[arizona98tj]

And I wouldn't limit myself to specifically that range of bullet weights. I would be willing to guess you can go with a bullet less than 55 grains and still maintain stability.