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vmathias
05-18-2013, 06:49 PM
I am sure there are formulas for this but was wondering if there is a basic standard I can follow to calculate energy and velocities. For example my 243 cast loads at 1700 fps are approx. 560 foot pounds at the muzzle.

How do I figure my velocities and energy's at 100-200 etc..
fcvan
05-18-2013, 06:52 PM
Vmathias, go to handloads.com and use their ballistic calculator. You can get velocity, drop, and wind drift. There is input for boolit size, weight, style which will give the ballistic coefficient which in turn factors into your trajectory. The link is

http://www.handloads.com/calc/index.html

There is a lot of interesting stuff there
jonp
05-18-2013, 07:57 PM
Do you have an Android? I downloaded a nice, free app that does this for any bullet. Input the info and you can get projected drift, trajectory etc...for about every caliber you can name
Von Gruff
05-18-2013, 08:36 PM
Her is the RCBS balistic coeficients which will give you something to works off

RCBS Cast Rifle Bullet Ballistic Coefficients
22-055 FN .159
243-095 .258
257-120 .272
270-150 .327
7mm-145 Silh. .272
7mm-168 SP .306
30-115 SP .175
30-150 FN .220
308-165 Silh. .286
30-180 SP .293
30-180 FN .255
35-200 FN .243
357-180 Silh .210
375-200 FN .220
44-200 FN .130
429-240 Silh .186
45-300 FN .207
45-405 FN .303
45-500 FN .365
vmathias
05-19-2013, 12:27 AM
Do you have an Android? I downloaded a nice, free app that does this for any bullet. Input the info and you can get projected drift, trajectory etc...for about every caliber you can name

No, I am still on the basic Pantech phone. Someday I will upgrade. lol.
303Guy
05-19-2013, 12:44 AM
Another useful ballistic tool is JBM - Calculations. You have to get the BC by relating to a similar bullet listed but you can put in your own values. Here's the link; http://www.jbmballistics.com/cgi-bin/jbmtraj-5.1.cgi
Larry Gibson
05-19-2013, 10:22 AM
Do you have an Android? I downloaded a nice, free app that does this for any bullet. Input the info and you can get projected drift, trajectory etc...for about every caliber you can name

So what is that app?

Larry Gibson