Does moly/HBN reduce barrel temp much

[1KBR]

The spotters in the pits have told me that my first 6-7 shots hold a very good group (so do my 5 shot group targets), but when I shoot 10 shot strings like in Williamsport with my lighter profile 6.5x284, my last few shots as the barrel heats up are always more eratic, with high and low shots. Without cleaning, accuraccy come back once the barrel cools. Since my 5 shot groups are so good, I,m reluctant to change my load, but was wondering if anyone has done any research or testing with barrel temps when using coated bullets, either moly or HBN.

 

[Catfish]

I tried Molly coated bullets in a 17 Rem. years ago. The Molly fouled my barrel so bad it lost all accuracy. I was able to get it to shooting again by fire lapping the barrel. By the time this all went down the barrel had abt 1,000 rounds down the tube, but if that had not worked, I was going to rebarrel it.

 

[jonbearman]

I have used moly for around 15 years and the way I coat them,I get no fouling.If you are using factory coated bullets that could be the problem as I feel they lay it on to heavy causing the moly build up. I have since gone the way of hbn as you use way less product and a pound would last me a long time and your hands dont turn black. I would shoot naked bullets then try very lightly coated bullets and I bet you would see a difference.

 

[1KBR]

I,m not too concerened about the fouling as I would still clean after each comp anyway, not giving HBN or moly enough time to build up or foul. It was more the temperature reduction I was after.