true bullet diameters

[ballistx]

I just took some measurements on some of my bullets. The 257's were measuring .255. Same at the very base. This was true on some 120's and 117's. Some 277's measured .274". 308's measured .306".

Is this common or just my bullets? Maybe it is a safety factor thrown in by the manufacturers?

It is an older Helios analog calipers. Can't believe it is off.

 

[Dosh]

Have you tried checking with another caliper?

 

[ballistx]

Don't have another one readily available. May pick up a digital one, but haven't had any need up till now.

This one is geared, smooth, zero's so don't see how it could have changed gear ratios midstream.

 

[rcairflr]

I;m afraid your caliper needs recalibrated or replaced.

 

[FearNoWind]

I too would suspect your caliper is either faulty or misaligned on the object. However, a micrometer is a better tool for measuring round objects like bullets.

 

[TracySes23]

I just took some measurements on some of my bullets. The 257's were measuring .255. Same at the very base. This was true on some 120's and 117's. Some 277's measured .274". 308's measured .306".

Is this common or just my bullets? Maybe it is a safety factor thrown in by the manufacturers?

It is an older Helios analog calipers. Can't believe it is off.

Use a 1 inch micrometer. They are much better suited for precision measuring on bullets.