155gn SMK Palma seating depth?

[Stevemopa]

I've worked up the charge and ended up with 47.0gns Varget in new FL sized Lapua brass with CCI BR2 primer, average velocity was 2864fps. The COAL is 2.775" as per Sierra manual and shot well at 100 and 200 yards(.662" and 1.525" 5 shot groups). I read somewhere that these bullets like a jump to the lands, can anyone confirm this? At the COAL used it is jumping .040" in my rifle. How much should I tighten it up, if at all?
On a side note, I recently bought a chrono and I'm wondering what most consider an acceptable standard deviation. My latest 10 shot string ES was 37 and SD was 11, the day before I fired a 5 shot string that registered ES of 19 and SD was 8. I understand that you want the lowest possible SD, but is a SD of 11 considered an acceptable number? Thanks for all input.

Steve

 

[Mudcat-NC]

Re: 155gn SMK Palma seating depth?

I think the general rule is a 20 thous jump with them. At least that is what I use and I am sure I am not the only one doing so. Though, I bet you find they work very well at more than one depth.

John

 

[Stevemopa]

Re: 155gn SMK Palma seating depth?

Thanks John, I'll work some up incrementally to .020".

 

[Heman]

Re: 155gn SMK Palma seating depth?

I've found all my SMKs including the 155 like 0.010" jump. Although when doing a test found then also liked 0.025" too.

 

[MitchAlsup]

Re: 155gn SMK Palma seating depth?

When I was using these, they liked to be in the 0.015 to 0.025 range or all the way back at 0.120. They did not like being around 0.050-0.080

{0.120 is magazine length in my gun}