142SMK OAL

[BarryL]

Heres a question for you cranial types. If a 142 SMK can vary by as much as .010" in OAL how much would this alter the BC?

 

[Spotcheck_Billy]

Many shooters trim the meplats on these bullets in an effort to make the OAL uniform along with eliminating the somewhat 'jagged' edge of the bullet tip. I believe that trimming the meplat takes about 2% off the BC. I know this isn't exactly what you asked, but it might help lead you there.

 

[BarryL]

I already trim the meplats. Just for something to do after trimming I checked a number of them and still found as much as .010" diff in them. Ran them through my Sierra program and figured a ES of 25fps plus a 2% diff in BC and came up with 19" vertical. Just wondering if this could be some of my problem.

 

[AlanPF]

I sort SMK142 by base to ogive always. Had one batch with a spread of 0.020! There are ways of deducing the BC difference - but I'd just sort them and remove the doubt.

Alan