SuperKirby
FG lives in one world - so what they do in Colorado should be universal, but if your regulations allow youshoot sabots go for it. And if your were to shoot conicals
I beleive there are better conicals out there (higher BC's and they load like a sabot).
Reading your description of what you have loaded successfully - and also reading that you will be shooting a the 44/300 grain XTP - I would suggest that you will need to get some Harvester Green "Crush Ribs" They are a slimmer variety of the 44 cal green sabots. I would also suggest to you that the 44/300 should shoot very well from your KRB.
I recently purchased one of the Knight Extremes with the MHC barrel on it and I can definitely verify what you are talking about "tight crown." Mine was so tight I would peel/shave the lead right off the conical as I put it in, but once by the crown the thing went down just fine. Also, when putting in sabots HPH-24's the crown would disort the petal(s) to the side slighly until by the crown and then it would slide down as designed. I ended up honeing the crown on my barrel to even the lands out. Another thing, there is apossibilty asyou shoot the barrel the crown may smooth itself out and become less of a problem.
The 44/300 should work dandy on whitetail and for the most part be an effective bullet on an Elk. The problem I havefound is when shooting the thicker skinned elk - there is a possibility of stripping the the lead from the copper - especially if you hit a larger bone. This usually occurs at closer ranges - longer shotsdo not seem to present the same problem as the velocity of the bullet has reduced significantly. Because of this Hornady did construct the XTP-Mag version of the 300 - but I think itis only available in the 45 cal. and it is notas effective as the regular XTP on whitetail at close range - it will shoot right through them without a lot of expansion.
One last thing then I'll get out of your hair... If you get a chance to get some Speer Gold Dot .452/300 bullets they are a bonded bullet and will not come apart + have great expansion at all ranges+ they have a pretty decent BC. Whit the tight crown you would need the MMP HPH-3p-Ez load sabot (pretty much the same thing as the EZ load TC sabot - or the Harvester black "crush rib." If you get the crown loosened up then you will be able to shoot the HPH-24 or the regular Harvester which will fit the bulk of your bore much better.
I would suggest you PM -Underclocked- on this forum he spent a lot of time working in a KRB with it's bore - He might have some really good suggestions for you.
Hey! good luck - hope all works out for you....