I bought a used Bushmaster M4 A3 16in barrel 1/9 twist. I'd been having trouble getting it to group well at 100 yards. Today I shot groups with Remington UMC Hollow Point 50gr and Winchester Supreme Silver tip 50gr. Both grouped about 1.5-2 inches at 100 yards. I was shooting from sitting unsupported with my drop down grip resting on the bench. I was able to keep it very steady. My foregrip is not free floated.
I noticed after unloading my rifle that the bullets are gouged after being chambered. I believe its the feed ramps that gouge the bullet. Could this be causing my loose groups or is 1.5-2 inches acceptable to most people?
Here is a picture of the gouged bullet, my fingernail would catch the gouges.
http://i33.photobucket.com/albums/d1...4/100_0963.jpg
Jon

