A while ago, another member posted a question regarding why there is no Winchester Data. I replied that Winchester doesn't really offer any serious powders to consider for 10 mm. So yesterday I was preparing for another Chrono session and thought "what the hey" and took out some of my W231 that I use for plinking in other calibers. Well, I kind of "guestimated" and picked a charge weight. The components are as follows: 180 Winchester FMJ bullet Winchester 10mm nickle cases CCI Standard large pistol primers 6.8 gr W231 Stock G20 except for 22# Wolff recoil spring The results are as follows in (fps): 1098 1100 1082 1077 1093 1099 1086 1089 1073 1079 Average was 1088 fps Std Dev 10fps This is very close to 1100 fps, pretty impressive for a plinking powder. Std Dev is pretty low too. I think the reason why the Std Dev is so low is because W231 "throws" and meters so well. Primers appeared not to be pushed out or flattened, and case bulge was not extraordinary. I haven't any idea if this is a mid or max charge. It doesn't appear to be a max charge. I feel reasonably comfortable with this load and don't feel compelled to push it farther. W231 burns about as well as any other. Finally, if the esteemed moderators feel that this thread can be used as a "sticky", then I kindly ask for you guys to consider making it one. Thanks, BuffaloBo Wanna kill these ads? We can help!