Being 5 bore at .98" (nominally .977"), this gun should shoot a 5 1/2 ball at about .960" to .950". That should give a ball of about 1,300gr. and use a cloth, the heaviest denim of 12oz. at .025" thick. This patching will hold the requisit amount of lube and give enough compression on the sides to keep the fouling soft enough to load anew. This compression and quantity of lube is vitally important to keep the fouling soft. Compression as little as .005" per side can work in nice smooth bores, especialy with low pressure guns such as this one.

So many wonderful guns being worked on and built here at Nitro-express right now. Exciting times.