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 M4 25-Meter Zeroing Target
jimmyhots  [Member]
4/19/2009 2:25:43 PM
Hi All,

Does anyone have an electronic copy of the M4 25-m zeroing target? Something high-quality and to-scale? I recently used the A2 target to zero my rifle per USMC 25m zeroing procedure, and it worked fine, but I'm using a 16" barrel and would prefer to have correct spacing on the grid lines for this rifle.

By the way I posted a write-up of my experience using the USMC 25m zeroing procedure if anyone's interested:
http://sites.google.com/site/jimmyhots/usmc25mar-15zero

Thanks,
Jimmy
David14  [Team Member]
4/19/2009 4:46:40 PM
M16A2 target here.
Looking for M4-specific one now.
R0N  [Team Member]
4/19/2009 5:06:05 PM
In almost 20 years in the Marines, I have never zeroed a M16A2 or A4 at 25m, you normally zero at 36 Yards, part of the reason is it takes 27 meters for the M855 round to fully stabilize.

M4s because of the lower MV are zeroed at 25ms, also the Z on the sight is for the A4, to allow it to be zeroed at same 25m range as the M4 (what the army does.)

From "MCRP 3-01A Marine rifle marksmanship"
Therefore a rifle’s BZO may be established at a distance of 36 yards/30
meters and the same BZO will be effective at 300 yards/meters.
To establish a field expedient BZO at 36 yards or 30
meters when a 300-yard/-meter range is not available,
a Marine performs the same steps as the zeroing process
outlined in paragraph 9006. However, since wind
does not affect the round at 36 yards/30 meters, windage
is not added nor is it removed from the windage
knob after confirming the BZO. To be accurate, the
target must be placed exactly 36 yards (or 30 meters)
from the muzzle of the rifle.
jimmyhots  [Member]
4/19/2009 6:21:08 PM
Originally Posted By R0N:
In almost 20 years in the Marines, I have never zeroed a M16A2 or A4 at 25m, you normally zero at 36 Yards, part of the reason is it takes 27 meters for the M855 round to fully stabilize.

M4s because of the lower MV are zeroed at 25ms, also the Z on the sight is for the A4, to allow it to be zeroed at same 25m range as the M4 (what the army does.)

From "MCRP 3-01A Marine rifle marksmanship"
Therefore a rifle’s BZO may be established at a distance of 36 yards/30
meters and the same BZO will be effective at 300 yards/meters.
To establish a field expedient BZO at 36 yards or 30
meters when a 300-yard/-meter range is not available,
a Marine performs the same steps as the zeroing process
outlined in paragraph 9006. However, since wind
does not affect the round at 36 yards/30 meters, windage
is not added nor is it removed from the windage
knob after confirming the BZO. To be accurate, the
target must be placed exactly 36 yards (or 30 meters)
from the muzzle of the rifle.


This makes sense since the first cross-over for most M4s is going to be at 30 meters (for a 300 meter zero). I outline this in a write-up I put together recently:
http://sites.google.com/site/jimmyhots/usmc25mar-15zero

So if I understand you correctly, you are suggesting that the zeroing target be at 30 meters, with the rear elevation on the rifle bottomed out. This seems the most sensible way to zero to me; put the target at the first cross-over and zero with the rear elevation bottomed-out, instead of zeroing at 25 meters or some other range that's not positioned at the first cross-over, and then monkeying with the rear elevation in an attempt to make the rifle "think" the target is at first cross-over.

JH
R0N  [Team Member]
4/19/2009 6:51:29 PM
When we use to shoot the A2s, we would BZO at 8/3 and at 36 yards or at 200 ms the the rear sight at 8/3-2; A4 would be 6/3 or 6/3-4 at the same range lines.
jimmyhots  [Member]
4/21/2009 12:29:07 AM
No one has a copy of the M4 zeroing target then?

JH
tpelle  [Team Member]
4/24/2009 1:04:00 PM
Originally Posted By jimmyhots:
No one has a copy of the M4 zeroing target then?

JH


Here ya go:

http://ohmr.ohio.gov/forms/ohmr2444-b.pdf
jimmyhots  [Member]
4/24/2009 3:00:27 PM
Originally Posted By tpelle:
Originally Posted By jimmyhots:
No one has a copy of the M4 zeroing target then?

JH


Here ya go:

http://ohmr.ohio.gov/forms/ohmr2444-b.pdf


Excellent thanks for posting!

JH
strat81  [Team Member]
4/24/2009 3:03:04 PM
Tag.
jimmyhots  [Member]
4/24/2009 4:15:11 PM
So here comes an obvious question. I know it's been asked before, but I've never heard a good, definitive answer. Why does the M4 zeroing target say to put the rear sight at bottom setting (i.e. 8/3 or 6/3), but the A2 target says to put the rear sight at 'z' setting?

To my understanding, the only significant difference between zeroing the M4 & the A2 is the spacing of the grid squares on the target to account for the increased sensitivity of sight adjustments on the M4 due to shorter barrel length. 25 meters does not fall at first crossover for either of the rifles, and therefore I would expect the M4 zeroing procedure to require the rear sight to be set at 'z' just as in the case of the A2.

Anyone know what the deal is with this?

JH