Mark, I wouldn't worry about 'wad collapse', rather just sticking to the published recipe. If you have a question call Alliant, they will always give you an up front honest answer to your question(s), something that is most refreshing in today's world.
Also, in the FWIW dept. 'Promo', according to Roster in a recently published article & if you look at any recently published chart, is virtually interchangabe w/Red Dot, i.e. same pressues and recommended charge weights, 100%! 'Promo' tends to be a bit denser, so you MUST use an accurate scale to insure correct weight is being thrown. I'd start about two bushing sizes smaller than what is recommended for Red Dot and WEIGH several charges before starting any serious loading & then weigh a few more after each 100 rounds irrespective of everything or anything; probably preaching to the choir here, but it never hurts to advocate erring on the safe side. Let Lou Reed keep the wild side;-) I have found 'Promo' is less expensive than Red Dot and plays the same tune.
Hope the weekend gives you good opportunity to try those loads out, at least on the plate.
What brand of #7 shot are you loading? Just curious.
kind regards, tw
