Sighting in my AR questions

[bigmtnman]

In order to get my eye lined up properly with a scope on my M&P I had to use a 1" picatinny riser and high scope rings (it's a seasoned citizen thing). This put the center line of the scope 3 3/4" above the bore. If I have only 25 yards with which to sight it in, where would I want my group to print at 25 in order to be "on" at 100 yards. I do not need to be precise, just ballpark. I'm using Federal Premium 55 grain FMJ. Thanks for any help.

 

[Eric300]

55 gr zeroed at 25 yds should put you pretty close to zero at 100 yds

A 50 yard zero, or roughly 1.3" low at 25 yards, also seems to be a good, useable trajectory––its highest point being about 1.5" high––at 125 yards–– then back on around 200 yards. IIRC a dead on 25 yard zero should get you within 2 inches of zero at at 100 yards

 

[Fishinfool]

Try this chart

Bore Scope Offset Calculator

Larry

 

[JT64]

I use 36/300 which is a Marine Corp zero and it works great for my M&P.
36 yard zero puts me right on the Money at 300


Sent from my iPhone using Tapatalk

 

[Scharfschuetzer]

25 yard zero for 100 yards

With that height of the sight above the bore and using your 55 grain load:

25 yards: -2.5"
50 yards: -1.4"
75 yards: -0.55"
100 yards Zeroed
200 yards -0.75"
300 yards -7.2"

What might be a better option for increased flexibility; much like the military uses and referred to above is:

25 yards: -1.85."
100 yards: +2.4"
200 yards: +4.0"
300 yards: Zero

The above figures are rounded off to the nearest .1." They were calculated using the Ballistics AE app.

 

[bigmtnman]

Thank you all ... That is EXACTLY the information I was seeking.

 

[Robspeire]

Thank you all ... That is EXACTLY the information I was seeking.

Me too. Just what I needed also. Sighting AR in tomorrow

 

[walnutred]

And if you are shooting well enough that you can measure the center of your groups consistently to the 100th of an inch, as in some of the above posts, you have my utmost respect. ;-D