Here are a few modifications I made to my Bushmaster based Carbine. As purchased the Carbine was somewhat of a pig and front heavy due to the Heavy Barrel configuration. I also found that the front sight base interfered with my field of vision as well as fast target aquisition using the Bushnell Holosight. The solid black color of the AR-15 was an issue for me as well. It quickly attracts the attention and recognition of the human eye due to the unique shape and shadow of the rifle.
The tools for this project were simple and consisted of a bench grinder, dremel tool, large and medium sized files, hacksaw, bench vise and GUNKOTE Molybdenum disulfide based firearm finish.
My first step was to remove the front sight base straight across with a hacksaw. I then performed the rough contour using the bench grinder and smoothed it up with hand files. This took about ten minutes in total.
Next I used masking tape and a sharpie to draw straight lines on the barrel beneath the handguards. I went over these lines with a dremel using progressivley larger cutting and grinding heads until the flutes were of sufficient depth. Most barrels are manufactured in HB configuration to reduce the amount of machine work. These commercial barrel diameters are in excess of the original M-16a2 thickness and way beyond the original design specs of the orginal Armalite AR-15 or later M-16A1.
After the fluting was completed I used a file to reduce the outside diameter of the barrel in order to save additional weight. To keep it fairly even I used a magic marker as a substitute Dykem marker to see where the high spots were after each pass with the file.
After all the metal work was completed I thoroughly degreased the rifle and applied the GUNKOTE solution per the manufacturers directions. I left the selector switch in the same position during the two or three coats required but this rifle is a tool and not some high paid runway model that needs her make-up just perfect so I don’t care. Spray paint will also work it just wont resist the elements and cleaning solvents as well.
Project completed. My Carbine is now about 1 lb lighter, better balanced, and provides a clear field of view through the Holosight after the mods. WARNING, WARNING!!! Do Not Try This At Home. These mods may result in unsafe conditions. I have fired around 750 factory and max pressure handloads through the rifle since completing the mods and feel confident the barrel has plenty of steel between the deepest cut and the bore. Rapid fire through the Holosight generally keeps 30 rounds in 12 inches at 300 meters. Anyway I am happy with the modifications. I will try to get some videos and more pics posted after my next range session.
