Ballistics-Projectiles 4

[metman]

I have searched the net but cannot find a link to answer my question. Maybe someone here would be able to provide a link?

I would like to compare lb-ft of energy at 50ft of 44 Magnum vs 45 w3.5" barrel/250grain, 180grain.

Thanks in advance.

Jesus is THE life,
Leonard

 

[desertfox]

Hi metman

Try this link, its a martindale online calculator:-

http://www.zvis.com/bali/bvtengy.shtml.

This link provides the list of ballistic calculators :-

http://www.martindalecenter.com/Calculators1C_1_Sport.html#SPORT-GU

regards desertfox

 

[funnelguy]

metman (Leonard),
Are you talking about handloads? 180 gr. seems pretty light for either of these calibers as a hunting load. Both calibers are suitable for some pretty tough critters with suitable bullets when loaded up to modern standards. Comparisons of muzzle energy would seem adequate for your purposes?

Looking at self defense applications, the energy and attendant recoil of the heavier loadings may be innapropriate.

 

[IRstuff]

Since the energy is simply mv^2, you can use a ballistics program to determine velocity downrange and do the math yourself:

http://www.stevespages.com/page8b.htm

TTFN

 

[funnelguy]

Great links DesertFox and IRstuff! There is also a forum here at Eng-Tips for ballistics, but it isn't very popular.

http://www.eng-tips.com/threadminder.cfm?spid=662&newpid=662

 

[Cockroach]

There are issues associated with this technology up here in Canada. None-the-less the industry survives under the watchful eye of our "liberal" federal government.

For projectile ranges of various projectile range(s) vs cartridge load the British Military Ordinace is probably your best source. I don't know if it is on line, but I have a very old copy of their circular entitled "High-Low Boom", if you can believe that. To my knowledge, not general public circulation which means no website information. E-mail me for a copy at "Sturni_Hueston@Yahoo.ca" and provide a mail address for the return.

I have several other American sources relating volumetric capacity and pressure ratings of solid propellant verse thermodynamic quantities that may be of interest. Again, public ban on information within Canada and to my knowledge, no "credible" website information.

Hope this helps you out.

Kenneth J Hueston, PEng
Principal
Sturni-Hueston Engineering Inc
Edmonton, Alberta Canada

 

[metman]

Thanks everyone for your input and especially funnelguy. I posted the question more appropriately for the forum he linked and he provided another link there which gave plenty of info including muzzle v & E and downrange v & E.

Jesus is THE life,
Leonard

 

[ccw]

Hi Metman,
Try to find the nearest bench-rest shooter club and get their help. They have high speed timer traps that can give the velocity very accurately at any reasonable distance from the muzzle. The ballistic chronographs I am familiar with, use approx. 8" x 8" clear plastic or paper squares, with plated conductor grids. The timer squares are supported on frames about 3' apart, so you get an average velocity Vavg within the 3' flight. You can use paper squares to sight in the sandbagged firearm, then rig up the timer trap. It should be fairly easy to hit within 8" at 50ft. Some of the more sophisticated traps use laser grids or light curtains instead of plated or painted conductor squares.
Bench-rest shooters use some unique and interesting techniques to assure extreme repeatability between shots. By testing you eliminate the predictive guesswork, but you may get data scatter in the results. These sophisticated shooters can help you reduce the scatter. Of course the energy in ft-lbs can be obtained from K.E. = 1/2mVavg**2