I think TAC is the better choice.  My experience with RL-15 in 35 Whelen, at least the lot I purchased, never gave me the velocities or
accuracy I was expecting.  But I only worked with the two 35 Whelen's that I own.  My two might not be representative of someone else's.  Don't get me wrong, it worked okay but never shined so to speak.  When I stumbled on IMR3031 in the Whelen and my .350 Mag I thought I had died and gone to heaven, at least with 200gr bullets I used for deer.  So far TAC has really helped me to get the
velocity up in my shortened Whelen.  Now the true test will be when I shoot for accuracy.  I know that IMR3031 gives super groups, albeit at a lower velocity than TAC.  I've already ran the 35 Whelen cases through the tumbler and wiped them off and as I was doing the clean up on them, it really dawned on me how easy a cartridge the 35 Whelen is to work with.  Just like the old 30-06, it just goes
about it's business without any fuss or muss and no scary surprises when working up loads.  It was 2006 until I bought my first 30-06
because I was never enamored with it, that is until I bought my first one.  Didn't own a 30-30 until 2006 either.  Always used the .32 Win Special instead.  Oh well, like we PA Dutch say, we get too soon old, and too late smart.LOL
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