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Old 04-01-2017, 06:49 PM   #5
Join Date: Aug 2004
Location: Buffalo, New York
Default Re: GURPS ULTRATECH ballistics?

Originally Posted by DouglasCole View Post
I'll get back to this in an hour or so; dinnertime now.
Thanks Doug.

I'm looking at your formulas for the EASY CONVERSIONS tab, and for the most part, I suspect that this is what I was originally looking at when I first made my spreadsheet.

Now, I'm looking at another formula that lists the formula of Muzzle energy as being equal to:

Muzzle Energy in J = Projectile Mass(g) x (velocity in m/sec)^2/2011

I was trying to figure out why the 2011 constant for the divisor was there, until I spotted the formula where Velocity in meters per second was spelled out. This formula works out to:

Velocity in m/sec = (Muzzle Energy(J)/Projectile Mass(in grams))^.5 x 44.84

When I factored out the various things, I came to realize the 2011 value is actually the 44.84 value squared (but rounded off). Even so, the two formulas that I'm looking at for Muzzle Energy in Joules (yours and Greg's) are off by about .528 percent (ie, negligible really).

More in my next post...
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