Both barrels have a fast twist for a .50 caliber gun, and are therefore intended to shoot conicals. They will shoot PRB, but may be " fussy " about the amount of powder used.
As to patch thickness, we can't guess. Neither can you. Patch thickness of a correct size is necessary for best accuracy with all RBs. You are going to have to use a micrometer, or caliper to measure the lead balls( don't trust someone saying they are .490"), the bore and groove diameters of your barrel, and then the thickness of the patches. Lube is also important. Different lubes can change group sizes in different barrels.
Part of the fun of this sport is discovering what works in a particular gun. We can give you guidance when you tell us dimension in thousandths( .001") of an inch, but you ( and we) need that critical information about the barrel and your balls and patches to help narrow down the choices for you to try. Dial Calipers can be bought on line for about $20.00. If you already own a micrometer, you can get old fashioned INSIDE calipers at your hardware store for less than $10.00. You take the measurement of these calipers with your micrometer. A micrometer, new, is going to cost you at least $60.00, and the better ones will cost twice that amount. You want a micrometer with the click adjustment for .0001". You don't need a digital micrometer- just another place to store dead batteries!, IMHO. Check the suppliers here for calipers and micrometers. Then do a little comparison price shopping locally."A Rose is a Rose, is a Rose..." The bard says, and that applies to calipers, too. :thumbsup: