Pop Math Quiz

[NorCalRifleman]

My barrel is 4140 Chromoly Steel. The external diameter of a portion I want reprofiled is .875". The section is 7.125" long. I want to trim it down to .700". How much weight will be removed?

The best reference for weight I could find was a place selling .5" rods that are 12" long and weigh .6682 lbs.

I'm not asking if this is worthwhile or what it will do to my accuracy, I just want the math.

[trilogy]

about .437 lb
Vbig=pi*7.125*(.875/2)^2=4.2822
Vslim=pi*7.125*(.7/2)^2)=2.741
Vbig-Vslim=1.5417=Vdifference
Vweight=pi*12*(.5/2)^2=2.355
(Vdifference/Vweight)*.6682=.437

--Matt

[D-FENS]

I get approximately .43 lbs

[NorCalRifleman]

Thanks, guys.

[Rogu3]

Aw, i came in late...i like firearm math