I don't know what available caps break up less. I had caps in the past that were much better in that regard, they didnt break up when fired, and had to be pulled off the nipple to reload, but don't recall what brand they were. I didn't really put the pieces of the puzzle together until reading in a book of a letter written during the Civil War by Major R.H.K.Whitely to Brigadier General J.W.Ripley, Chief of the Ordnance Department, stating "First, a cap suitable for Colt's pistol does not suit either Savage's or Starr's, because the main spring is too weak to explode it. Second, a cap suitable for Savage's or Starrs pistol does not suit Colt's, because the hammer drives it to pieces, a fragment often lodges in front of the cock, and renders the arm useless after the first fire. On this account our spies carry two pistols, and have had to depend on the second for safety for the reason above stated. Therefore, I am compelled to have two qualities made, one for the Colt's answering in thickness of copper to Ely's double waterproof, and for the other for Savage's and Starr's to Ely's metal lined."
Ripley forwarded the letter to Major W.A. Thornton at the West Troy Arsenal and requested the he 'please see that all the revolvers made for this Department are suited to fire the same caps as Colt's army pistols'. (fron "Guns of the American West, p 69-70, by Joseph Rosa)
It would seem that what's taken for granted regarding caps breaking up today, wasn't the issue in the past we assume it was. Percussion guns are basically hobby items in the market today, and nobody makes caps specifically for Colt type pistols to reduce cap fragmentation.
I've shot small game like cottontail rabbits and squirrels with 45 Colts, 45-70's with lead bullets, and with 50 cal round balls. They just make large clean holes through them, no problem with having meat left.