Range Report Need (SG) gyro stability factor for a Sierra 142MK

[silentbushmaster]

Contacted Sierra with no luck. Anyone know the SG factor
for a 6.5 142 Sierra Match King and a 6.5 Nosler 140 Ballistic tip? Thanks in advance.

 

[2Shots]

Re: Need (SG) gyro stability factor for a Sierra 142MK

Don't you need a velocity to calculate this and a twist rate?

 

[gstaylorg]

Re: Need (SG) gyro stability factor for a Sierra 142MK

Definitely need to have the projectile dimensions, velocity, and twist rate. Alternatively, if you know the dimensions and a reasonable estimate of the velocity you expect, you can determine a twist rate necessary to achieve a specific Sg by inputting different twist rates here:

http://www.jbmballistics.com/cgi-bin/jbmstab-5.1.cgi

 

[silentbushmaster]

Re: Need (SG) gyro stability factor for a Sierra 142MK

I appreciate the link, easy to calculate now. Thanks