Humidity has been extremely variable here this year. First time I tested the JSG it was low(probably less than 40%) one of the hot dry days we've had this summer.The day I got lousy groups it was high (80 - 90%) one of the sauna-like days following a rain. I wasshooting loose fffg JSG, and the thing I really noticed was the lack of recoil on some shots. Some shots felt totally normal, and some felt like I was shooting a very light charge. (first low recoil shot I even checked the powder measure to be sure I had poured it all downbore ) What had (& still has) me confused was how it was so variable on recoil that day. Same rifle, same caps, same powder charge as the day it did so good.

NMRog,
Is a crossbow legal where you hunt? I have bone spurs in my left shoulder and switched to a crossbow a few years ago for deer hunting. The crossbow is a different way to launch an arrow, but it has about the same range and accuracy as a good compound bow. Luckily, here in Ohio it has been classified as legal archery equipment for many decades now and I didn't miss a day of archery season.
If it's legal, and you decide to get one, I highly recommend Excalibur!