Help my feeble mind comprehend this

Bocephus

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Took my BPM Patrolman AR, some 55gr .223 and my new Strike Eagle II (1-6x24) scope to Frontline Defense this afternoon to sight it in then bang some steel on their 500 yd range. I sighted in at 25yds, knowing it should be about right at 300 yds. If you are not familiar with their AR BDC reticle, it has hash marks under the crosshairs that, theoretically, allow you to be on paper at 100 yd increments.

Anyway, took it to the 500 yd range and, after 3 elevation clicks, was hitting the 300 yd steel with the crosshairs in the center of the target. Transitioned to the 400 target, put the next hash mark on the target and pulled the trigger. No ding, no dirt, nothing. Started playing with sight picture but never got close until I put the center crosshairs on the upper third of the target, then was hitting steel. Hmmm, okay. Transitioned to the 500 target, put the next lower hash on the middle of the target and same as the 400 yd, nada to go by. Played with position of the crosshairs and was able to hit steel if the center crosshairs where lined up with the top of the target. After playing some more, I found that holding the crosshairs a little below the target worked for 200, center worked for 300, upper third worked for 400 and top of the target worked for 500.

I (now) know the center crosshairs are meant to be zero’d at 50 yds and you should be good from 20-200 yds. Then the 4 lower hash marks are supposed to be close enough for 300-600 yds. But, to my feeble mind, I shouldn’t be able to hit steel from 200-500 yds with minimal change of the position of the crosshairs on the target when using a 25 yds zero, right? Magic bullets, lucky SOB or clueless wonder that has no business owning anything more powerful than a .22 and only if shooting out to no more than 100 yds are the only things I can come up with :)
 
Forgot to mention that the 2-500 yd range has an elevated platform (~6ft high) that you shoot from. I know this plays into trajectory but shouldn’t have that much effect, right?
 
What power setting did you do the sighting in at and the shooting at the steel?
If I remember correctly they all need to be done at 6x, check the paperwork.
 
Zero can be done at 1x, the hash marks are for 6x. I can’t remember what magnification I had it at once I moved to the 2-500 yd range. All of this was actually done yesterday and I barely remember starting this thread.
 
My only BDC experience is with my ACOG

I know if you line the stadia/line across the SHOULDERS of the target, you will get center mass/sternum hits ie lower than your point of aim. The scope is designed like this

I realized this one day when shooting at 400yds, all my hits were dead center but 6” below the black when shooting an F type (head and shoulders) silhouette. If I aimed across center head (ear eyes ear), rounds struck the torso just below the neck.

Perhaps your BDC is designed similarly
 
My only BDC experience is with my ACOG

I know if you line the stadia/line across the SHOULDERS of the target, you will get center mass/sternum hits ie lower than your point of aim. The scope is designed like this

I realized this one day when shooting at 400yds, all my hits were dead center but 6” below the black when shooting an F type (head and shoulders) silhouette. If I aimed across center head (ear eyes ear), rounds struck the torso just below the neck.

Perhaps your BDC is designed similarly

Could be and I will have to read up on my particular scope more.

I guess my biggest question (and admittedly I probably worded it wrong), is how is a 55 gr .223 round appearing to shoot so flat? I can see a little change in POA from 2-300 yds but I should be having to have more of a holdover when going from 300 to 400 or 500. The targets could be larger than I perceive but it looks like I am only changing my POA about 6-9” when transitioning from 300 to 400 and then again when going from 400 to 500. If they were man-sized targets (and they are not), my POA would be sternum to shoulders to top of head and it should be closer to 25” from 3-400 and about 40” from 400-500, shouldn’t it? Or am overthinking this and should turn off internet access for at least the next week? lol
 
Could be and I will have to read up on my particular scope more.

I guess my biggest question (and admittedly I probably worded it wrong), is how is a 55 gr .223 round appearing to shoot so flat? I can see a little change in POA from 2-300 yds but I should be having to have more of a holdover when going from 300 to 400 or 500. The targets could be larger than I perceive but it looks like I am only changing my POA about 6-9” when transitioning from 300 to 400 and then again when going from 400 to 500. If they were man-sized targets (and they are not), my POA would be sternum to shoulders to top of head and it should be closer to 25” from 3-400 and about 40” from 400-500, shouldn’t it? Or am overthinking this and should turn off internet access for at least the next week? lol

My drop at 300 yards is 18”. I cant remember the others off the top of my head
 
The scope is designed for a 200 yard zero. The top of the post will be 100 yards. The center dot will be 50ish yards, and 200 yards.
By going with a 25 yard zero (bullet going up at 25 and coming down somewhere around 300), you have stretched your zero out a lot. It's going to have less drop at say, 400, than it would with a 200 yard zero. As the bullet is coming down from it's ballistic arc at these distances.

Not exactly sure if this answers your question.

Edit: it's not really shooting "flat" as your bullet is likely 9-10" high at around 180 yards.
 
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The scope is designed for a 200 yard zero. The top of the post will be 100 yards. The center dot will be 50ish yards, and 200 yards.
By going with a 25 yard zero (bullet going up at 25 and coming down somewhere around 300), you have stretched your zero out a lot. It's going to have less drop at say, 400, than it would with a 200 yard zero. As the bullet is coming down from it's ballistic arc at these distances.

Not exactly sure if this answers your question.

Edit: it's not really shooting "flat" as your bullet is likely 9-10" high at around 180 yards.

Thanks. I had a feeling using a 25 yd zero would cause issues with the drop out past 300 yd and the hash marks, just thought it wouldn’t have been this much. I will zero it at 50, set the magnification to 6x, tune it at 200 and see how that works.

Flat was probably the wrong term to use but glad you got my point anyway :)
 
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Thanks. I had a feeling using a 25 yd zero would cause issues with the drop out past 300 yd and the hash marks, just thought it wouldn’t have been this much. I will zero it at 50, set the magnification to 6x, tune it at 200 and see how that works.

Flat was probably the wrong term to use but glad you got my point anyway :)

That's what I would do. Or, what I actually did do when I owned that scope. It should line up a lot closer to the BDC hashes.

It's important to get that fine tune at 200 as good as you can with the ammo you will most likely be using, imo.
 
The scope is designed for a 200 yard zero. The top of the post will be 100 yards. The center dot will be 50ish yards, and 200 yards.
By going with a 25 yard zero (bullet going up at 25 and coming down somewhere around 300), you have stretched your zero out a lot. It's going to have less drop at say, 400, than it would with a 200 yard zero. As the bullet is coming down from it's ballistic arc at these distances.

Not exactly sure if this answers your question.

Edit: it's not really shooting "flat" as your bullet is likely 9-10" high at around 180 yards.

This right here ^
 
FYI, the stadia lines are drawn assuming a certain load with a certain zero. The more you change those parameters, the less your stadia lines will match the bullet trajectory.
 
You didn't mention the relationship between the amount you held high to connect vs the hash marks. Were the two distances similar? If so then it was just your reference that was off due to zeroing at the wrong distance for that BDC.
 

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You didn't mention the relationship between the amount you held high to connect vs the hash marks. Were the two distances similar? If so then it was just your reference that was off due to zeroing at the wrong distance for that BDC.

That info is in my rambling. Essentially, I never really left the crosshairs from 200-500 yds. I think I may have been at 2x when I started shooting the steel, which started me down a rabbit hole I didn’t recover from until today :)
 
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