Hello there. Thank you for the feedback. I will look for some 158 grain slugs that have the round nose profile to use as much as I am a fan of Elmer Keith and the SWC bullets. I will continue to experiment with loads and bullet types to see what I can find to shoot well in the M64. I will also keep in mind to look for an adjustable sights model as well for the ability to tailor the sights to the loading not vice versa. Kind regards.