Is there any way to estimate muzzle velocity without a chrony?

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Tikka223

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I don't have a chronograph (I really should buy one) so I'm curious if there is any way to estimate muzzle velocity so that I punch it into iSnipe or whatever to help me get on target at know distances.

For example, my T3 Tac seems to like 69gr SMKs being fired with 26gr of Varget out of a 20" barrel.

A zero at 100m is easy but then to zero at 600m without a huge piece of paper would be nice.
 
Use an app like shooter that has a velocity calibration feature. Find a zero at 300 meters and calculate the velocity from the drop using the app. It will get you close. The most accurate velocity calibrations are found at longer ranges, Ive done this quite a bit and it works pretty well.
 
You need to use an interior ballistics program like Quickload.

It allows you to plug in all the variables such as bullet type and weight, seating length (gives you usable case volume), powder charge, barrel length and twist and a pile of other data.

Based on all the data you put in Quickload runs an algorithm and calculates a pretty accurate velocity estimate. My experience has been that the Quickload estimate is well within 50 fps of actual velocity when you run your load over a good chronograph.

It's sister program, Quicktarget imports your data from Quickload to create exterior ballistics charts based on your specific information.
 
Sterlok is also a decent one for the android and ios platforms and it allows you to store your 5 favorite loads amd rifles to quick refference them have not tried quickload will test that one once weather improves
 
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Couldn't resist
 
Quickload is not an app. It's available only from Neco in California. He's old school so you get it on a CD. ww w.neconos.com
 
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Zero it at 100 and shoot it at 400... measure the drop. Velocity can be calculated with the bullets BC and the drop over 300 yards I believe. It's so much easier to buy a chronograph.
 
Check out Vortex Optics site , click on LRBC. Give it load info, it does the rest. happy happy happy
 
Chronos... I don't have much faith in them. Ballistic's is a science. If you can get accurate drop data for various distances and have accurate weather data, you can fill in the blanks for other ranges and conditions.

In my lap right now is a box of federal 180gr powershok's. Advertised velocity is 2960 fps. My chrono reads them at 3100ish fps. My field data verifies them at 3136fps.

My chrono reads my 210 Berger load at 3030ish, field data 3063fps.

Both those have been tested and verified at 50y intervals out to 400y repeatedly and now verified to 800.

I'd be way off if I used the manufacturers data and still a little off if I relied on my chrono.
 
A chronograph is an invaluable tool. If you are going to try and back-calculate your velocity using measured drops at different ranges though, I would recommend going out a lot further than 400 meters to where the trajectory starts dropping off a lot more.

A quick example using ballistic data I have for my 223's 75 gr A-Max load (2795 fps at the muzzle, 100 meter zero), I get 9.0 MOA up adjustment required to be on target at 400 meters. Just playing around in my ballistics program, I can go down to 2755 fps muzzle velocity and only need 9.3 MOA up. I can go up in muzzle velocity to 2838 fps and then only need 8.7 MOA up. Assuming I can shoot consistent 0.6 MOA groups at 400 meters, this gives me an 83 fps spread where the true velocity can be. This can add a lot of uncertainty when stretching out to longer ranges. Of course maybe this is close enough if you can spot your splashes and aren't worried about first round hits at longer ranges
 
I back calculated for two rifles and I did it at the ranges where the bullet would go drop below 1400 fps it took some shooting but I now have drop charts that are within one or two clicks at all ranges. Shooter apps do work. There is a new one called applied ballistics which is likely the best one. Bryan Litz has a DVD set about long range shooting and it describes really well how to use the app and also shows shooting examples of him using it.
 
As this is posted in the precision rifle section....there is no way to estimate it close enough for precision.
 
Knowing the MV won't tell you much. Knowing how to read and interpret ballistics tables will.
Think in terms of roughly 108"(9 FEET) bullet drop at 600 for a 69 grain bullet. If you're sighted in at 100, do the arithmetic for the adjustment on your scope. IE 1/4" per click is 48" per foot. You may not have enough adjustment on your scope though.
Your manual should give a range of velocities too. Then you guesstimate.
You do know that 600 yards is way too far for any .223, if you're hunting?
Anyway, Sierra has a ballistics program on their site. There are several out there. Oh and forget about your phone.
 
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