I've never tried Trail Boss. Two reasons: they sell it in 9 oz cans, and pressures with it are NOT low, even if velocities are. That fear of double-charging big cases and small charges has not ever concerned me, so that isn't a factor either. Many have great luck with it for your purposes. Can't argue with results!
How consistent are the speeds you're getting out of the 35 Whelen? Any accuracy tests? I've been wanting a Whelen to do exactly what you've described here. And, to fling a few 225gr bullets at elk.
