I built a .54 English Sporting Rifle with a 32" Rice Jaeger barrel and a Chambers English Fowler lock for our off-hand shooting contests. I could not shoot it well off-hand, it only weighs 7.5 pounds. But I fitted new sights, which helped, and hit a foot-ball sized rock at 110 yards with my last two shots after testing the loads listed here. I tried some JoAnn's Fabric linen, which crushed to .009, but it holed, too thin a weave for my use. At 50 yards from rest, the lower right target is 50 grains (antler measure, really weighs 52 grains) of Goex 3F and .530 Hornadys. This grouped well even if the patches holed. I changed to a heavier linen patch for 50 grains of Olde Eynsford 3F on the lower right, but the barrel doesn't like that powder. (You can hit Control and the Plus sign to enlarge the photo).
A closeup of the 50 grain targets. The fouler shots were on a separate target, plotted here.
The second day's test with exactly 50 grains of each. This barrel did not like the OE 3F, but the velocities are the same as with Goex 3F.
Here is 80 grains of Goex 2F on the left, 80 of OE 2F in the center and 80 of OE 3F on the right. The velocities are about the same, the OE 3F some faster, shot the next day after a sight change.
Here is 80 grains of OE 1 1/2F on the left and 100 of OE 1 1/2 on the right, at 1703 fps. My 31" Bridger Hawken averaged 1744 fps with this load and an .008 linen patch. I reshaped the sights after this shooting, the shots should be in one fat hole like on the top right. This rifle is moving on to a new owner. I have another .50 Rice Jaeger barrel like this one, but don't know what I will make with it. I thought this was a good off-hand rifle for me, but I shoot my 10 3/4 pound Bridger a lot better. Still, I hit a football-sized rock offhand at 110 yards with my last two shots after this testing, so I guess I got used to it. I want a flintlock for our matches and am just finishing up a .58 halfstock flint mountain rifle, patterned closely after the Bridger.
A good source of linen is
www.homefabricsonline.com. They have 347 linens. I got my soft canvas from their store in Idaho Falls, ID, item 210881, at $6.99 per yard, which is 36" wide by 60" long.