I'm a new AR-15 owner and was wondering what kind of ammo I should buy for range shooting.  My AR has 1 in 7" twist.  How does the amount of twist affect what weight of ammo I should buy?  (55g, 65g, 75g, etc.)  

What difference will having different weighted bullets have on my accuracy?  

Is there a brand quality thershold I should stay within to not adversely affect my gun?

WOLF has some very cheap ammo, like $100 for 1000 rounds.  Is this stuff OK for me to use?

Thanks to anyone who can help me.

Briefly, the weight of the bullet is not the real factor that determines the appropriate twist rate. It is the length of the bullet. The reason that bullet weight is used so often in reference to twist rate is that, generally, when a bullet is made heavier, it must be made longer. Since the diamter of the bullet cannot be altered, the only way to add weight is to make the bullet longer. The longer the bullet is, the faster the twist rate needs to be in order to stabilize it during flight.
Some bullets of the same caliber can actually be lighter, but longer. This is due to the materials used to construct the bullet. For example, a 30 caliber bullet of 165 grains, can be shorter than a bullet of 163 grains weight if the 163 grain bullet is armor piercing. Since steel or tungsten have a lower weight per unit than lead, the same weight of steel will take up more space than the same weight in lead.This makes the bullet longer, but of less weight than a traditional lead bullet of the same weight.

Thw 1:7 twist rate of your barrel means that for every 7 inches that the bullet travels down range, it will rotate 1 time. Generally, for that rate of twist in a 22 cal barrel, the 69gr through 80 gr lead/copper bullets will provide the best performance.

/nitpickmode ON

tungsten 19,2kg/dm³ >  lead 11.3kg/dm³

/nitpickmode OFF

Quoted: I'm a new AR-15 owner and was wondering what kind of ammo I should buy for range shooting.  My AR has 1 in 7" twist.  How does the amount of twist affect what weight of ammo I should buy?  (55g, 65g, 75g, etc.)   What difference will having different weighted bullets have on my accuracy?   Is there a brand quality thershold I should stay within to not adversely affect my gun? WOLF has some very cheap ammo, like $100 for 1000 rounds.  Is this stuff OK for me to use? Thanks to anyone who can help me.

1. Usually,the heavier the bullet--the quicker the twist ----the lighter the bullet----the longer the twist.
   In most cases,a 1 in 7 twist likes heavier bullets ( 68gr all the way to 80gr)
2. The changes in bullet weight will change youre accuracy and POI
3. There are several brands of ammo to choose from,just a matter of finding out what works best in youre rifle----kinda costly$$ if you dont reload.
4. Been using Wolf ammo for yrs------if you do go the Wolf way as far as ammo-----be certain to use the ammo that doesnt have the lacquer coating on the cases-----if you do use ammo that has the lacquer,youll  have to clean you rifle sooner than usual,especially the chamber----hope this helps
   As Brouhaha suggested-----------------------------read the topics at the top of the forum