The Treso flash holes to me, always seemed too small. I like the TOW stainless steel replacement nipples. They have a smaller flash hole than the usual stock nipples but take the Remington #10 cap perfectly.
With over 15 perCUSSIN' revolvers, I've been called the Imelda Marcos of cap & ball.
SASS#3302 (Life), SASS Regulator, NRA (Life), DGB#129
Wolverton Mtn. Peacekeepers (WA), former Orygun Cowboy (Ranger, Posse from Hell)