.030 worked best for me, most people report the RDF's aren't jump sensitive but when I tested them in my rifle I found that while them all shot good .030 shot best. Are you getting consistent seating depth with 40.9 gr of H4350?
On my old barrel I went up to 41.0 with H4350 without any pressure issues but havnt tried it in my new barrel cause the varget load shoots so good. If you run low on H4350 or have problems finding it give varget a try. 37.5 gr shoots lights out with my rifle with single digit SD's
Base to ogive is .772 if that helps, I have no idea what the smk’s are. The rdf work well with a jump
Just to get my data in here for someone that might be able to use it... I use a Ruger Precision Rifle with a Snipe Arms 6.5 Creedmoor barrel 20 3/4" long. I use 40.5 gr of H4350 and it produces 2650 fps. It will put 5 rounds in a target at 100 yds. with all holes touching each other. Basically makes on "large" hole. I use it for long range competition... typically 1000 yards. I shoots very well and is very consistent. I shot LOTS of varying loads to nail down the best jump gap and settled on .020". It was just a whisper better than .030". Could probably use either and get the same results. The .020" gap does have a down side of not being able to use a magazine, since the loaded rounds are too long to accomodate them. So I use a Bob Sled loading block to make single round loading easier.
