Are there any websites that give ammo velocity data for specific barrel lengths? I have a Ruger 556 with a 16 inch barrel and I'm looking for ammo data for this barrel length.  I've done many searches and haven't found anything yet.



Thanks!

Ballistics by the inch .com?

Yup, but not a TON of data.

http://www.ballisticsbytheinch.com/calibers.html

Canned velocities might get you close, but you can see pretty large velocity spreads between two identical length barrels shooting the exact same ammo.

If you’re just wanting to get a rough idea for calculating terminal performance ranges you might be OK, but if you’re looking to figure out precise drops beyond a couple hundred yards, your best bet is going to be buying a chronograph.

If it's a specific brand you're looking for (or even multiple) just email the manufacturer.

In the end, it's just a rough estimate until you get a chronograph.

Thanks for the info, yeah did not think I would get exact data but may be close. Any who Ill try contacting ammo makers and see what they can tell me and then I'll decide to get a chronograph or not.

Simply you need a chrono to have any kind of accuracy.

If you're just trying to figure for hitting steel out to like 4-500yds, the internet should get you there and you can figure the rest.

If you're getting into reloading and want to copy a factory load that your rifle likes to save ammo costs on, say a premium bullet that you'll use a lot of for Prarie dogs or shooting matches, etc... you could work up to what is safe, and then work back until your drops at range are the same.

So you get the load in the ballpark and then go like .2gr increments until your 100yd zero or whatever has the same drop at 300 that the factory stuff does, but likely with much tighter groups. If you're lucky, they'll shoot the same POI to zero so you can use either ammo without worry.

You of course MUST use the SAME bullet, which is going to be hard to do with say a 55gr .223, but could very easily be done with say winchester power points or nosler varmageddon (insert whatever name brand bullet offered in factory ammo that you might use).

Using common bullets with known BCs, you could also measure your drop (along with height over bore and all that shit), plug it into the calculator, and play with the input velocity until it lines up. That ought to get you +/- 25fps if you have good environmental data, and can print good groups at a decent range. I would probably use 300yds at a minimum.

True your muzzle velocity. Assuming you have 600-800 yards to play with.

Agree get a chronograph a lot of things affect the  velocity. Cold air and moist air is more dense your velocity your velocity will be slower the on a dry warm day.

Moist air offers less resistance actually. It's counterintuitive, but that's how it is.

You can take 2 identical guns, and fire the same load, and see different velocities

If you want real data, use a chrony.

...anything else, is hearsay

.

https://youtu.be/KaOEyGeWDdk

Probably overkill for what OP is trying to do. But it's Sniper Jesus .

With that being said, I do use a chronograph also.

Barnes has load data for shorter barrels on a lot of cartridges, including 16" data for 5.56. It's just data for their bullets which being copper tends to differ somewhat from the same weight lead bullets but it is still useful data. Short of that there is gordon's reloading tool and quickload.