It's streaks, looks like scratches. Sorry it's in the grooves. Changed it. Thanks. I don't have any fire cracking yet. I'm using RL16 powder and only shooting 5 shot strings and never let the barrel get hot, RL16 is dirty. So it could maybe be streaks. What ever it is, it won't come out with C4 carbon remover and a tight fitting bronze bore brush. I'm going to try Thorro Clean.
I clean my barrel after every time I shoot. Within a hour. There were a few little srteaks and I let them go. Then each time a little more until every time it gets little more until I"ve seen enough and accuracy is falling off. I waited to long to do something about it.
Ah.
I didn't have the problem in the summer using 4350 powder, then I got the Lapua 144's and switched to RL16 powder and gained 100 FPS and an increase in accuracy , but I need to clean more often with the abrasive. Now I know, Thanks for the advise. I only needed an abrasive before in my AR'S.
I see why you feel that way. I just spent 2 hours getting all the carbon out because I waited to long. It's a lot easier getting out of an AR 15 and not waiting so long.
I have been thinking of what you said and, how many rounds do you get out of a barrel? It seems that maybe if I want an extra 100 fps it's going to cost me more than I thought. And for me and what I'm doing it might not be worth it. Even with a 400MOD barrel.
The only way to stay ahead of hard carbon is to remove it. Brushes and solvent only remove the easy stuff.
Steve personally I think you're on the right track getting the carbon streaks out. Do those streaks that look like scratches go straightforward down the bore? If so that is caused by the carbon itself. Carbon is very hard and can leave a path of streaks. Cleaning the black out of the streaks is OK but not the streaks. You can actually cause more damage by trying to remove them. Removing the black carbon streaks and the copper is all that is necessary. Sounds like you have good resolution in your bore scope.
Thanks for the response and advise. I just got done looking at another 6.5 Creedmoor rifle barrel, with my bore scope , with the exact same barrel and round count, but never used RL16 powder in it. The barrel has far less streaks from carbon. I have been doing some reading and finally woke up to the fact that I need to buy some JB Paste and use it often to keep the carbon in check before I need a more aggressive cleaner. I could not figure out what those marks where from. So thanks again.
JB bore paste is even more aggressive. I'd stay with Iosso or Thoroclean they're about the same. You bore scope will tell when it's clean.
Everything I read said the opposite , when JB Paste is used with Kroil it is less aggressive and takes longer. Thanks for the heads up, I will try both and report. The reason I'm so concerned is I have a new 30" barrel that has not been shot yet and I'm going to bore scope it first and keep track of it from day one.
^Yep. With factory barrels it can build up pretty quickly too. If you are shooting a nice stainless, cut match barrel with 5R rifling it may never build up.
I've used many tubs of JB Bore paste and many tubes of Iosso/Flitz. And, a few people on here have done tests with the three.
I just watched a bunch of videos on bore cleaning and the streaks I see are pretty common. I have been mislead looking at my DD 300BLIK barrel that still looks like a chrome bumper. I don't even need to use a bronze brush to clean the barrel burning 296 powder.
