Scott F,
I figured that's why you posted the .22 Hornet may not be the best example, but since somebody else cited their experience with the Hornet as well decided to clarify.
By the way, I also have not been able to get enough 1680 into the K-Hornet case to cause any problems--or even come close to matching Li'l Gun velocities, which is what I've experienced with 1680 in the standard Hornet.
I also sometimes wonder how much 1680 varies from lot to lot, as I've seen some people claim faster velocities with 1680 than I've ever seen. Right now, however, I have three different lots of 1680, and am about to test them out. Am doing an article on variations in powder lots, as well as how powders have varied over the years. Have some original H4831 and H4198 from decades ago that am going to compare directly to today's production.
