TY Captian.I have experienced a sudden change in zero after using that copper fouling solution,the rifle went back to its original zero after a few rounds and the fouling had built back up,I think the buidup in the barrel provides a better seal and effects the pressure.

I should have said softer jacket than the bullets I normally hunt with. As the Barnes does.
Have you fires any of the Swifts. My understanding is the loading data is a bit on the mild side because of the softer jacket.

I've fired 160 grain Swift A-Frame in my 7mm Magnum. It is definitely not a round to use high-intensity loads with. The factory loads chronograph typically between 2875 and 2910 fps MV. Others who have chronographed them say its the same with theirs. Weight retention in these bullets is very high.