I've been shooting a swift since the 70's,and I have found them to be a little particular as to loads. But once you find it they usually are tack drivers. I shot IMR4064 and a 55 Grain Ballistic Tip for 20 years, till I finally had to rebarrel. When the rifle came back to me, it didn't like 4064 at all, but loved 38 grains of RL15 and a 55 Ballistic tip. 3 shot bug hole groups. I wish you luck. Oh BTW, I neck size all my Swift brass.
Jerry
