How To Question????

[Jim Hundley]

What is the most accurate proceedure to measure the berring surface of a bullet?What type of measuring tools are needed?
Thanks for any help!
Jimmy

 

[MagMan]

Bearing surface comparator.
BSC

 

[Jim Hundley]

Thanks,Magman.

 

[HoytemanPA]

Davidson Seat Depth Checker

I use this one for $14.

If you find inconsistency in measurement, Take a bullet that you are most likely going to be using, coat it with JB and lightly spin it in the tip of the checker. Measurements are very repeatable, I do base/ogive readings on the bullets. You can do bearing surface if you get two, but I've quit doing that. Tool is also invaluable to document loaded round OAL (to ogive). I don't use the base attachment for the cartridge head, just the nose piece.

Bullets have really come around in the last two years. Three years ago I was finding .020 variance this year it is down to somewhere around 90% +/- .001 8% +/- .002 2% +/- .003

Thanks goes out to Hornady, Sierra, and Lapua!