MMP makes a number of different sabots in different thickness levels. So depending on how tight a barrel you have, you can order a sabot that seals the bore well and does not need a hammer to load..

HPH-12 are the standard thickness sabots
HPH-24 are thinner and more easy to load then the HPH 12
The three petal I have never used but heard they are easy to load.

Also harvester makes sabots. They have standard sabots and then the crushed rib. I use the crushed rib in a lot of my rifles... But they are easy to load. Also the sabots come in standard and high pressure. That is determined by the length of the petal and thickness of the base. Sabotloader can explain all of this to you much better then I, and since he shoots Omega's he might have some excellent suggestions for you as well.