Home Forums Reloading Varmint Rifles eratic groups

I had just finished working up a load for my new upper receiver, after getting the scope zeroed in I fired my first group at 100 yards, not good at all, one round hit six inches above and one inch to the right of my point of aim, another round hit dead even but a inch to the left and the third round was six inches low and an inch to the right. After allowing myself to cool off I changed magazines and fired three more rounds, this time they all were slightly left and looked like a three leaf clover, group measured .879. he only thing I did different other than change the magazine was that I waited a minute between shots instead of thirty seconds, wind started to blow so I quit for the day, is it possible that the magazine was the reason for the bad group, both magazines are Magpul 30 round magazines.

Not an ar expert. But shouldn't make a diff. Unless there is enough drag to keep the bolt from rotating fully....guessing here.... If you hav a forward assist try bumping that befor each shot with that mag....would. Be interested to know...

You say yo just finished setting the scope, possibly the stadia of the reticle wasn't firmly in place yet, and took a couple of shots to set in place. Used to happen with scopes in the past, rare these days but never know.