AR ballistics question.

[BlackHogDown]

A buddy is at the range and asked a question I couldn't answer so I figured I'd turn to the gurus.

He's got an EOTech holo and was shooting first at 25 yards. From what I understood, the several in the 9 were the first four. Made adjustments and proceeded to pour them into the 10. Again, just at 25 yards.

When he moved back to 50, his first three rounds were grouped high.

Thoughts/suggestions as to why?




Sent from my iPhone using Tapatalk

[BlackHogDown]

Has the flight path of the projectile simply not flattened out yet at 25yds? Am I overthinking this?

[Gbird]

Anything within 25, you have a mechanical offset. Basically, if you're sighted in at 100, and move in to shoot, you will need to aim 3-4 inches above your center to hit center. That is my best guess.


Sent from my iPhone using Tapatalk

[kmon]

With an AR you are starting out with the line of sight 2 to 2.5 inches above the line of the bore. if 2.5 inches above line of bore for say the Hornady 55gr amax factory load you are sighted in for 400 yards with a 25 yard zero and will be hitting high for all distances between 26 and 399 yards. at 200 yards the bullet should be about 10 inches above the line if sight with that 25 yard zero.



For a 100 yard zero try 1.5 inches low at 25 yards

[DesertDug]

with a 25 yard sight in he will be high to about 200 yards

[kmon]

A lot og where it will be on at has to do with sight height above bore. Not sue where an eotech will put that measurement so you could be correct. With my AR the centerline of the scope is 2.5 inches above bore.

Hornady has a handy ballistic calculator that will put it in 25 yard increments

https://www.hornady.com/team-hornady/ballistic-calculators/#!/

[DesertDug]

A lot og where it will be on at has to do with sight height above bore. Not sue where an eotech will put that measurement so you could be correct. With my AR the centerline of the scope is 2.5 inches above bore.

Hornady has a handy ballistic calculator that will put it in 25 yard increments

https://www.hornady.com/team-hornady...alculators/#!/

ya thats where i went to see where he would be hitting, but used 1.5" over bore.

anyway, if he is sighting in at 25 it would be on the rising point of the the diagram shown above. He will be high till he reach where the bullet crosses the second line of sight. Not sure I am using the right terminology.

[kmon]

Getting your point across sir, basically with about any sight in there will be 2 points the projectile is dead on and everywhere else it will be either lower or higher than the line of sight. Hope our posting helped BlackHogDown answer his question

[BlackHogDown]

Indeed it did. Thank you, gentlemen

[Hudson05]

Bullets fly in an arc.

[hellbndr23]

I sight my eotech at 50. Close enough to dead on at 200.

Sent from my HTC6545LVW using Tapatalk

[talleywack97]

In basic training i was shocked that we zeroed our weapons at 25meters and at 300 theyre was no hold-over(dead on). That was tough for an lever action guy to grasp. Seein that i always zero at 100 yd. And i have quite a bit of hold-over at 300