223 scope zero at 25 yards

[DNS]

At 25 yards where should the bullet inpact in relation to the cross hairs of the scope? 250 yards is the intended distance for long range zero with this rifle.

Thanks, Mike

 

[The_Pretender]

For a 55 grain bullet:

A tenth of an inch low at 25 yards.

 

[DNS]

Yep 55 grain.
Darn, I was dead on and adjusted it a half inch up. I'll try again tomorrow.

Mike

 

[The_Pretender]

A half-inch up would net you a 325 yard zero.

 

[The_Pretender]

Your 250 yard zero gives roughly:

1.1" high at 50 yards
2.8" high at 100 yards
3.2" high at 150 yards
2.5" high at 200 yards

 

[benEzra]

What kind of rifle are you using? A mini-14, an AR, and a bolt-action .223 have vastly different sight heights, and that affects trajectory a LOT. Your sight-in with an AR will be much different than that of a rifle with a lower sight height.

 

[viking499]

Are there charts somewhere that tell all this information? Or are you just getting it out of a reload book or bullet website?

 

[Kwanger]

+1 benezra....also it will depend on how high the scope is mounted - carry handle/riser/flat on a flat top rail, etc - there are lot of options which will affect the equation.

 

[WNTFW]

See post by benEzra
Height over bore has a bigger effect than most people realize.

In my experience you can get close. I have been off by a big margin a few times. The only way to know for sure it to verify at the 250 yard range. All the variables being identified going into the equation helps. The less the variables are known the more error possible.

 

[benEzra]

Are there charts somewhere that tell all this information? Or are you just getting it out of a reload book or bullet website?

Viking99, the best approach is to get a free ballistics program, plug in your load/sight height/desired zero distance, and let it tell you what the trajectory looks like.

I have an iPhone, so I actually bought iSnipe for a couple dollars from the App Store, but there are lots of free ballistics programs for the PC.

 

[viking499]

What is a good PC based ballistics program?

 

[ZXD9]

I use PointBlank which is free. You can get it over on HuntingNut.com

 

[ssyoumans]

Nikon spoton

I like the web based Nikon Spoton. It has most factory ammo and bullets for reloading. It allows you to adjust for your scope height and velocity out of your barrel. You can compare 3 different loads. Generates printable tables and graphs, all the basic stuff you could need.

http://www.nikonhunting.com/SpotOn

 

[Maverick223]

What is a good PC based ballistics program?

+1 for PointBlank, as well as BigGameInfo.

 

[basicblur]

What is a good PC based ballistics program?

I have the previously mentioned free Point Blank, but find myself using free Remington Shoot software.
I also got "standard" info on zero ranges, but after investigating found most of the conventional quotes didn't make any allowances for scope height, and since I have ARs...

The Remington Shoot software graphs are real eye-openers-you just plug in your scope height, zero range, and bring up a trajectory graph.
Really helps you decide at what range you want to zero something with a higher scope height like an AR.

 

[UniversalFrost]

tagging this for later use at home to compare my actual real life results with some of the free programs you guys mentioned.