A 6MMPPC that shoots 100 grain bullets is possible but rare. The 6MMPPC has a 1 in 14 twist compared to 1 in10 for the 243 and 6MM Remington. That twist is to slow to stabalize all 100 grain bullets and was the reason that the 244 Rem. (Renamed 6MM REM) failed while the 243 Win was a success. The 6MMPPC is a 243 caliber but uses only about half the powder charge of the 243 casing. Thus the 243 will develope an additional 400-550 fps using the same bullet weight. The PPC was developed for target shooting and makes a good varmit round. The 243 and 6mm Rem as well as the 240 Weatherby were made to be dual purpose varmit/medium game cartridge. I limit the 243 to varmits as well. However thats because I had less than ideal success with the 6's as deer rifles. When that happens you get sour on a cartridge and its hard to change an opinion based on bad expierence. I had problems with it that I have not had with the 25's.