Quote Originally Posted by jmg8550 View Post
Well my upper is in the mail being sent back as we speak, they said it had no problems and they tested it with 69 grain match ammo from Federal and Remington. Hopefully they included a target. They also said that 55 grain bullets are too light for a 1-9 twist barrel and I should shoot no less than 62 grain pills. Is this really true? It is a 16 inch barrel with a standard M4 hand guard. They didn't say how well it grouped. I should receive it Monday. It's about time though, they've had it since the beginning of January. I understand it has been cold, but this long to get it back? Springfield's turn around time has been 3 weeks tops for me, and I've sent stuff to them 3 times so far for various work to be done.
i have a few different brands of 55gr. swing by the house and i'll put a shooters ammo box together for you. my SBR and the spouses ar shoot 55gr great and both 1:9 .
i found the 55 and lighter ammo say 52gr's really shine in my 20" 1:12