The .17 AH is my carry gun through the summer. I shoot the 19 grn. Calhoon bullet and push it to 3,600 fps. I`ve seen post were some guy are claiming 3,900 with Lit`le gun, but the only powder I`ve tried is H-4227. When I got to max. loads with it I was getting groups of about 1/4 min. and have been so happy with my first load that I`ve never tried anything else. One thing bad about it though is that presure jumps very fast in this small case. When working up you load do it on a hot day and increase you powder charges by 1/10 of a grain of powder at a time. Case forming is easy. Just run .22 Hornet cases through your seating die and then through your sizeing die, no form dies required. If you get one I would recomand getting a tight neck chamber and this will require neck turning. If your not already a wildcatter this is really not a good round to start with unless you can get live advice from someone with experance in wildcating. The load I shoot is point blank, no more than 2 1/2 in. high or low, to just over 290 yrds. and that`s with 10.4 grns. of powder. It will drill a .30 cal. hole in a piece of 1/4 in. steel. If you have any more questions you can PM me.