Sighting in Thumper.

[Baxter]

Hello, first post here. I was wondering if I sight in my 16 inch upper @ 25yrds what yardage will it be flat till? I am keeping it irons for now and hoping to get a deer on sunday.

[MudBug]

First off.. Welcome. I know that the whole "First post needs approval" thing is confusing, but it makes dealing with the spammers easier. I deleted your second post (which I assume you made because you didn't see this one) just because it was a duplicate, not because you did anything wrong.

Now.

I ran this awhile ago and if you are running a 16" barrel it will look kinda like this

25 yards = 0

50 yarrds = +2.2"

100 yards = +4.7"

150 yards = +4.3"

200 yards = +0.5"

250 yards = -7.2" where you still have close to 1000 pounds of energy. This I believe is the end of the useful range for the 450b on large game.


I hope that helps.

[Baxter]

Thanks Eric.I wish that was a stickie somewhere. I have been looking all over for this info. Thanks again.

[Siringo]

Go to Hornady's website. They have a ballistic program that you can use. They also list ballistic Coffiencents for their bullets that you can plug in and then play with the sight in ranges.

[bushmeister]

That's handy MB, can you run it again for 2" high at 100 yds?

[MudBug]

That's handy MB, can you run it again for 2" high at 100 yds?

Sure.

That would be zero'd at 35 yards.

35 yards = 0

50 yards = +0.8"

100 yards = +2"

150 yards = +0.4"

200 yards = -4.8"

250 yards = -14.1"


The program I'm using is not the most uber accurate, complicated program, but it works great for figuring out where I want to zero something for what I want to do.

It's the Norma precision Ballistics program on THIS PAGE over at the right, choose Ballistic US. The BC for the 250 grn SST is 0.210 (at least according to midway, I can't find it on Hornady's page). And in general the sight height over bore for an AR15 is 2.7" (This is for the standard sights, and what most mounts will give you. If you are using some combination of rings and scout rail or just tall rings you will need to measure your own Sight Height over bore)


Mess with it a bit and you can adjust the sliders for zero and see how it effects the trajectory.

Here's what it looks like Link to Screen Shot

[thatguy]

Baxter - Welcome!!

MudBug - I think the link to the ballestics calculator needs to be a sticky OR post the results for different zero ranges. I was wondering the same thing but was taking at "wag" at 2" high at 50 would be close enough out to 150 or so yds

brian

[thatguy]

Thanks for the Norma link Mudbug.. that ballestics calculator is great to play with..

thanks again

brian