petasux
First, I would tell you that you should never need a starter to get a sabot/bullet combination down. The ram rod and a palm cup of some sort in the field and @ the range just a plain old range rod. If a short starter is required you really need to think about changing sabots. It is one of those perpetuaited myths that a sabot has to load hard to shoot well (and in the same breath it can not load to easy either). I should say that appplies to the new "polymere" sabots the old plastic ones that was a somewhat different story or in the Savage.
Originally the iniatial sabot supplied with the Shockwave was a Harvester - then a switch to MMP - the first MMP sabots supplied with the shockwaves, and it was a large run of them, were HPH-12's They will load but good luck.... the next run of SW came with HPH-24's. These are all black sabots... It sounds like you have either the older Harvester of the newer MMP's (Harvesters have a smooth cupand MMP's have a stair stepped cup on the powder end). Today TC and MMP have made a new yellow super glide sabot that is suppose to work really well - Ido not use the SW so I can not really tell you. That sabot is under contract to TC so MMP can not sell it to the public - but they did from that develop the black 3 petaled sabot that really workswell in tight barrels.
mike