I reload for 7mm-08's as well. I've always had issues with getting the neck/shoulder junction clean. Not on any other calibers, just the 7/08.You may think this is the simplest thing in the world but in 45 years of reloading I've never seen this before. I have 100, once fired Lapua cases that I'm getting ready to load for my grandson's 7mm-08. They have been in my sonic cleaner for an hour and my vibratory cleaner for over three hours. Problem is, I can't get the carbon off the necks! I can knock it down a bit with steel wool but it still leaves the stains. Anybody have a cleaner or cleaning method that will get it off? Help!
The method that has worked the best for me is: load the tumbler/vibrater with fresh walnut media,(no brass yet) turn it on, add 2-3 ounces of brasso pouring it around the running tumbler/vibrater. Let it run 5 minutes or so, so that the media and brasso gets well mixed and the brasso will get dry. Now add your brass and let it run 3-4 hours. they will come out like polished diamonds.