Sighting in New Pew Pews at Short Range

[Sgt.K]

I am very familiar with the 25 to 250/300 zero used during my time in the Army and why it works given sight offset and trajectory. I have a friend with a number of ARs who wants to get them sighted in, preferably under controlled (read: indoor) conditions. King Shooter Supply is relatively convenient but only has 15 yards. My google-fu has so far failed to turn up an offset for zeroing at that distance, i.e. "1 inch low at 15y would be point of aim at 25y and again at 250/300y". I don't want to give him bad guidance.

So, what say y'all? Anything like that out there, or am I oversimplifying things in my head?

[cephas]

I use this, 10 yds, to get started:
http://jerkingthetrigger.com/wp-cont...ero-Target.pdf

Edit: this is for 50-200 yd zero. sorry.

[CycleTech]

I am very familiar with the 25 to 250/300 zero used during my time in the Army and why it works given sight offset and trajectory. I have a friend with a number of ARs who wants to get them sighted in, preferably under controlled (read: indoor) conditions. King Shooter Supply is relatively convenient but only has 15 yards. My google-fu has so far failed to turn up an offset for zeroing at that distance, i.e. "1 inch low at 15y would be point of aim at 25y and again at 250/300y". I don't want to give him bad guidance.

So, what say y'all? Anything like that out there, or am I oversimplifying things in my head?

If I where zeroing at 15 I would figure at 25 would be the same.

[Spaceballs]

If I where zeroing at 15 I would figure at 25 would be the same.

The difference in impact point between 15 and 25 yards will be small, but there will be a difference.

At 200+ yards that small difference grows to be noticable

[Spaceballs]

I use this, 10 yds, to get started:
http://jerkingthetrigger.com/wp-cont...ero-Target.pdf

Edit: this is for 50-200 yd zero. sorry.

This works really well

And while it is for 50-200 it's still good at 300 yards depending on your needs

If you are looking for competition level precision, it's not good enough

If you are hunting, and know to compensate for about 1.5 inches drop you'll get over that additional 100 yards out to 300, it'll be okay

With that 50/200 yrd dope your point of impact at any distance between 0 and 300 yards will be within about 3 inches total (1.5 inches above the muzzle. 1.5 inches below the muzzle)

Actual milage may vary depending on bullet weight, spin, and muzzle velocity.

[bigandy1966]

I think the distance of the cross hairs in the scope to the centerline of the bore is taken into consideration, if theres a 2" height it will vary if theres a 3" height at 50 yards.
I usually go for 1" high at 50 for 223/5.56 and this will print at 2" high at 100 yds and dead on at 225Attachment 153058

[ar15jules]

I am of the opinion that to know what your setup will do with a particular ammunition, you just need to shoot it at various distances. There is no substitute. I think everyone knows this.

[jthrelf]

I am of the opinion that to know what your setup will do with a particular ammunition, you just need to shoot it at various distances. There is no substitute. I think everyone knows this.

Agreed, the short sighting distance will give you a starting point though.

I'd suggest running the ballistics for a 50 yd zero and see what if should be at 15 yds. To know this we need to know velocity, projectile weight, and height over bore of the optics and/or sights. I think the 50yd zero is superior for 5.56.

I have the Federal app on my phone and it works for this purpose.

[Spaceballs]

Agreed, the short sighting distance will give you a starting point though.

I'd suggest running the ballistics for a 50 yd zero and see what if should be at 15 yds. To know this we need to know velocity, projectile weight, and height over bore of the optics and/or sights. I think the 50yd zero is superior for 5.56.

I have the Federal app on my phone and it works for this purpose.

Short distance doping is really nice when you have sights that could be WAY out of whack.

At 10 yards you will be on paper even if your sights are on sideways. Makes it easy to make that first major correction.

Trying to sight in at 200 yards that way and you are putting rounds god only knows where. Makes it tough to get on paper where you can make the finer corrections.

And sometimes a 25 yrd indoor range is all someone has. When I lived in Maryland that was pretty much your option. It's a little different here in PA it there are many places where a 25 yard Lane is what you've got available.

[Brick]

Here's a very good source for ballistic calcs it also has a separate function to determine point blank range just set you zero for 15 yards and your interval and you'll show where your far zero falls.

https://shooterscalculator.com/balli...tory-chart.php

Norma also has a very good ballistics calculator where you can define your own bullet then slide the variables around graphically to view the changes.