I found that in my SP1 a charge of 20.5 to 21.5 grs of 4198 with a 55 gr FMJ bullet would go into about 3/8" at 100 yards all day long. If I use a good HP bullet in the 52 or 53 gr range it would shoot even tighter groups.
I found that in my SP1 a charge of 20.5 to 21.5 grs of 4198 with a 55 gr FMJ bullet would go into about 3/8" at 100 yards all day long. If I use a good HP bullet in the 52 or 53 gr range it would shoot even tighter groups.