Last night I attempted to change out my bushmaster A2 upper for a LMT A3 upper. The barrel that was on the A2 and moved to the A3 was a 16 Heavy barrel Bushmaster.
1.) When inserting the barrel into the A3 I twisted the barrel around to get it into the Upper. It seem as though the feed ramps on the barrel slightly scrached the inside of the upper. Is this normal?
2.) After finishing the project I loaded a 10 round bushmaster mag to check for fit and function. I cycled all ten rounds out of the unit using the charging handle. All rounds fed fine but after looking at the rounds the bullet seems to have some small scratches on them. Is this normal?
Sorry Im a newbie. Just making sure that Im doing this right.
1. Not an uncommon occurance IMO.
2. Unless your cycling snap-cap rounds, you should NEVER cycle live rounds in the manner in which you described to determine the functioning of your new build. The "functioning" aspect of your new upper should be done properly by firing live rounds at an approved range or safe location.
And yes cycling rounds in the manner which you did will leave small dings and marks on both the bullets and the brass.
Make sure ya check out the www.ammo-oracle.com tacked to the top of the Ammunition Forum, as well as the Tacked topics elsewhere as they all contain great info.....