ATN 4K pro 5X20 Ballistics question

[jlarkin]

I'm sure this is the stupidest of questions. But I'll ask anyway. Be kind...I'm a newbie to hunting lol!

When entering velocity in the ATN ballistics is this from muzzle (3,020 fps advertised velocity) or do I enter velocity given at 100 yds on the box (2656 fps). I will of course zero at 100 yds.

Thanks all

[odin]

It is muzzle velocity.
remember always that your scope is first and foremost a computer.
Without information it is a useless box of circuts. With information it turns into a sweet little tool that will put a hunk of lead exactly where you want it - user error adide that is.

[jlarkin]

Appreciate that. Thank you.

[mexicanjoe]

Remember what it asks you for in the optic.

Sight height = middle of bore to middle of lens.

Set range at 100 in profile zero and on measure tape in scope (I missed that and caught it after).

Ensure you zero on a calm day and check all of your environmentals.

Best rest you can find/make. You have to take all human factor out of your zero. It’s just rifle, optic and ammo. Human factor come while hunting so take the weapon out of the error solution.

I now take all of my mounts off and remount with locktite. Every one of them once o get proper sight height and eye relief.

I have made all of these mistakes in the past.

[retired]

Also, a lot of the published numbers are from a 24" test barrel. There are several tests results posted on the internet for 223/5.56 for the velocity loss per inch reduction in barrel length. I have a 16" 5.56 and I use 3130 fps as my starting velocity. The absolute best method is to use a chronograph to test the different loads in your rifle.