CaptainMal
Silver $$ Contributor

Replaced my Dasher barrel with a new one. That old barrel had been "compromised" with carbon build-up. It was cleaned religiously with a variety of solutions but none obviously worked until I used C4 and Iosso paste.
This is the tuner-brake I had on that old barrel for the last 1,000 rounds. Put it on the new barrel, shot a few rounds yesterday and looked. Now this tuner was always cleaned out with C4, a brush and patches on a pistol rod.
Forget it. I could see the carbon build-up in the ports in spite of my cleaning. Used a drill bit and LOOK.
Darn near 1/2 a spoonful of carbon when I brushed it into a pan after the picture. No wonder I had trouble inside the barrel.
Testing yesterday with IMR 4166 showed spikes in velocity and pressure as things got close to 3,000 fps. Going to just use Varget again. Darn I wanted to get away from all this carbon that goes with Varget use.