Here is my first kill with the Ruger Old Army my Father-In-Law gifted me. It was a 25 yard shot quartering away hard. Entry at front of ham, and never recovered the bullet, but it did stay inside the hog. She weighed prolly 100-120# and ran 75 yards.
I could be wrong but I think it will hold about 38 grains by weight with that bullet and still clear the cylinder face- with no wad. About an eighth of an inch below the mouth of a 44mag case. I melt lube around the bullet to seal the cylinder on mine.
I use well lubed bullets and don't seal in front of the bullet. My cylinder shaves a ring of lead when seating, so I don't think a spark can get in there. From everything I can read about chain fires, it seems a loose cap is the biggest threat. I load the chambers with Pyrodex about 1/4" from the top of the cylinder, and then seat the bullet just below the rim. I think I measured it at 35 grains. Shoots better than I can. Haven't chronographed it, but guessing around 950-1000 fps.