How high will a bullet travel?
How high will a bullet travel?
(OP)
I want to make a spreadsheet that calculates how high different caliber bullets will go if fired straight up. Note that this (actually firing straight up) is something that should never be done in any corcumstance.
So I have the muzzle velocity, the bullet weight, and the drag coefficient. Let's assume we're firing from sea level. I do not know how to employ the drag coefficient, and am not sure how to take into account thinning air as the altitude increass. Please help!
I can do this calc no problem if we assume we're in a vacuum, just convert initial kinetic energy into final potential energy. Just not sure how to take the air into account.
So I have the muzzle velocity, the bullet weight, and the drag coefficient. Let's assume we're firing from sea level. I do not know how to employ the drag coefficient, and am not sure how to take into account thinning air as the altitude increass. Please help!
I can do this calc no problem if we assume we're in a vacuum, just convert initial kinetic energy into final potential energy. Just not sure how to take the air into account.





RE: How high will a bullet travel?
F=1/2*rho*Cd*A*v^2
Note that the drag coefficient varies substantially with speed, especially in the transonic region.
Cheers
Greg Locock
SIG:Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips.
RE: How high will a bullet travel?
I can tell you that a 105-mm APFSDS round is supposed to reach about 21 km altitude at 45ยบ superelevation as calculated by a VERY expensive simulation program.
TTFN
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RE: How high will a bullet travel?
may help
Cheers
Greg Locock
SIG:Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips.
RE: How high will a bullet travel?
I would not consider this calculation a fundamental one. In a vacuum it's first week high school physics. Add the air of varying density and it's not exactly a cakewalk.
RE: How high will a bullet travel?
RE: How high will a bullet travel?
As to the variation of atmospheric density with altitude
ht
The program I mention above takes both the change in Cd and rho into effect.
Cheers
Greg Locock
SIG:Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips.
RE: How high will a bullet travel?
TTFN
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