is it common to see unburned powder in barrel, have 7.5 barrel…using good ammo. winchester ane federal 223…is barrel to short for all the powder to burn, or is this normal…ps there’s no problem, gun works fine…just really dirty after 100 rnds.
most likely yes, its the short barrel
yes & as is mentioned for that reason.
That makes sense if you think about it. Most pistol cartridges contain 5-9 grains of fast burning powder to propel bullets out of 4-6 inch barrels. .223 contains three to five times that amount of propellant to push the bullet out of a 20 inch barrel.