Similar experience.
My experience with Moly coating and Barnes TSXs is after shooting 15 moly coated nosler and hornady bullets in test loads I switched to TSXs and fired 12 of them down the barrel. The first 3 were 1/2 moa, second 3 were 2" and the last 6 minute of 6" target. The barrel should of had a coating of moly still left in it. It wasn't a good experience at all. It took 1/3 of a jug of CR-10 to get all the fouling out and about 60 patches. After I removed all the fouling it’s back to 1/2" groups with the nosler moly coated. I won't try the TSXs till after hunting season is over.
Am I willing to shoot TSXs, not until the barrel is squeaky clean of all other fouling. Then the barrel must be cleaned before shooting any other bullets.
I have the moly kit maybe I'll coat some TSXs and give it a try, but right now the TSXs are shelved.