If you own a Sumatra you know that pushing pellets into the cylinder can be difficult if you use the Ein Jin pellets as they are seemingly a size too big. Well, I have the .25 and getting the 43gr pellets to go in is practically impossible for me. I got frustrated trying to load them a little while ago and started looking around for something that might work. Well, low and behold, I find an old dead "AA" size battery. The positive side (the side with the bump) works PERFECT to push the pellets in, and since it's very short, it won't shove the pellets right out the back. It pushes them in the perfect distance to allow for effortless re installation of the 6 shot rotary cylinder back into the gun. The battery will last a few years before it starts to eat itself away and make that white powdery stuff that can burn your hands. If it starts to do that, just get another recently dead "AA" battery and replace it.
It worked great for me and I hope it can work great for you! The battery method should work fine for .22 also as it's not that tight of a fit in my .25, but I can't make any promises!
Oh, and hi everyone! I have a .25 Sumatra and an old 1960 or so Benjamin 312 .22cal air rifle. I love shooting them both!