Old Cane,
I have used both bullets, I have not used the speed loader. The only problem I have with the Hornady bullet/sabot combinations are that I normally can not get the sabots down with standing on the ram rod. And the second reason bullet/sabot packs a really expensive. Thompson Center offers the same bullets under a different name with a thinner sabot - but I don't think they have the speed sabot yet.
As for the two bullets any of the XTP's SST, or Thompson Shockwaves will handle deer just fine if propelled at a decent rate.
I shoot XTP's for all my recreational and target shooting they are accurate. And if you buy them in boxes of pistol bullets and purchase sabots separately - money wise you come out way ahead.
If you are shooting a 50 cal you might look into getting some .458 sabots from MMP or Knight and shoot them. The 300 grain Hornady .458 (45-70) is a rifle bullet and works realy well. With a 50 you have lot of options in production bullets.
I am to the point of suggesting to most people - you have to find the sabot that works best with your barrel, because not all sabots are the same even if they are the same size. I have found that for the most part Nosler sabots work in all of my ML's
I am not a Power Belt fan - they work great on paper but, I have seen some poor performance on game, but then again I have seen regular bullets that didn't work that well either.
Does your state allow the use of sabots? if they do keep on working you will find the right combination. If they don't I would really look into the 460 grain No Excuse bullet. After doing some research they look awful good on paper.
