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M.O.A.
09-22-2012, 03:40 AM
Is there a way to calculate your velocities with out a Chronograph? ? ?

efm77
09-22-2012, 07:29 AM
Not that I'm aware of. I think without a chronograph you're just guessing since each barrel is different so will have different velocities from what manufacturers or reloading manuals post.

scope eye
09-22-2012, 07:33 AM
Even factory loads are not even close

Luckus
09-22-2012, 08:51 AM
Chronographs are not that expensive anymore. I bought a ProChrono a couple years ago with the remote for around $125.00, and it work great. Luckus

thomae
09-22-2012, 09:06 AM
Is there a way to calculate your velocities with out a Chronograph? ? ?
Borrow a friend's or go to the range and when you see someone with one, ask REALLY NICELY if you could fire some shots through it.

However, if your groups are good and you aren't getting pressure signs, I know it is interesting, but what is the value added of knowing the velocity, other than personal satisfaction?

nsaqam
09-22-2012, 09:23 AM
Of course you can. At least a pretty close approximation.

Shoot a well zeroed bullet of known BC at 300-500 (or more) yards noting accurately your drop at those ranges.

Finding accurate BC's can be difficult but the G7 numbers from Bryan Litz for Berger bullets are regarded as being very accurate. Bryan Litz's numbers for other bullets are very accurate as well and can be found in his book.

Plug accurate BC's and environmental conditions (altitude, barometric pressure and so forth) into a good exterior ballistics program such as JBM.

http://www.jbmballistics.com/cgi-bin/jbmtraj-5.1.cgi (http://www.jbmballistics.com/cgi-bin/jbmtraj-5.1.cgi)

Then adjust the speed to where the program drops match your actual drops and you have a pretty accurate measure of speed for your rifle at your location.

nsaqam
09-22-2012, 09:25 AM
All that said, a Pro Chrono Digital is a fantastic, inexpensive chronograph and will serve you well.

M.O.A.
09-22-2012, 03:03 PM
Of course you can. At least a pretty close approximation.

Shoot a well zeroed bullet of known BC at 300-500 (or more) yards noting accurately your drop at those ranges.

Finding accurate BC's can be difficult but the G7 numbers from Bryan Litz for Berger bullets are regarded as being very accurate. Bryan Litz's numbers for other bullets are very accurate as well and can be found in his book.

Plug accurate BC's and environmental conditions (altitude, barometric pressure and so forth) into a good exterior ballistics program such as JBM.

http://www.jbmballistics.com/cgi-bin/jbmtraj-5.1.cgi (http://www.jbmballistics.com/cgi-bin/jbmtraj-5.1.cgi)

Then adjust the speed to where the program drops match your actual drops and you have a pretty accurate measure of speed for your rifle at your location.
That is what I was looking for thang you

efm77
09-22-2012, 06:48 PM
+1 on them not being that expensive anymore. I got a Shooting Chrony with remote screen for less than $90 on sale and it works great.