Results 1 to 8 of 8

Thread: Best 7.62 BUIS zero distance?

  1. #1
    Join Date
    Dec 2006
    Location
    Tennessee
    Posts
    11,762
    Feedback Score
    0

    Best 7.62 BUIS zero distance?

    7.62x51 or .308 to be more specific. Requesting some input: Was thinking about the 50yd IBSZ (POA/POI at 50y). This will be for the folding BUIS, using M80 Ball or equivalent. Okay or any better suggestions?
    Last edited by ABNAK; 05-17-20 at 18:33.
    11C2P '83-'87
    Airborne Infantry
    F**k China!

  2. #2
    Join Date
    Dec 2013
    Location
    AZ
    Posts
    1,332
    Feedback Score
    3 (100%)
    I feel like in the short range; 556 and 308 are very similar. So my suggestions would be either the 50/200 or the 36/300. I have always felt a longer zero is better for iron sights because they don't have the aiming point of a dot or reticle. Maybe even the 25/400 would be good for irons?
    Tactical Nylon Micro Brewery

  3. #3
    Join Date
    Apr 2007
    Location
    FL
    Posts
    9,325
    Feedback Score
    28 (100%)
    What projectile at what velocity for shooting at what target in what conditions?
    Jack Leuba
    Director of Sales
    Knight's Armament Company
    jleuba@knightarmco.com

  4. #4
    Join Date
    Aug 2009
    Posts
    4,383
    Feedback Score
    16 (100%)
    Without further info, I always default to 100yd zero for everything 5.56x45/7.62x51

    There are certainly reasons to deviate but in a vacuum (and my personal situation), that is what I do and recommend.

  5. #5
    Join Date
    Dec 2006
    Location
    Tennessee
    Posts
    11,762
    Feedback Score
    0
    Quote Originally Posted by Failure2Stop View Post
    What projectile at what velocity for shooting at what target in what conditions?
    M80 Ball (or equivalent) out of an 18" barrel, flattest trajectory for about 300m.
    11C2P '83-'87
    Airborne Infantry
    F**k China!

  6. #6
    Join Date
    Apr 2007
    Location
    FL
    Posts
    9,325
    Feedback Score
    28 (100%)
    Quote Originally Posted by ABNAK View Post
    M80 Ball (or equivalent) out of an 18" barrel, flattest trajectory for about 300m.
    M80 out of an 18" tube is going to be around 2600-2700 ft/s, so let's go with 2650 MV.
    You put this into the "Beyond 5.56" rather than the "Other Guns", so I'll assume an AR-based rifle with standard height irons sights, for a 2.6" LOS over bore.
    2" high at 100 yards (basically a 200 meter zero) will give you a max height of 2.25" at 130 yards, POA/POI at about 190-235 (+/1.2") and about 7" low at 300 yards.
    In meters, that's a max height of 2.25" at 120m, POA/POI at 175-215m, and 10" low at 300m.
    Jack Leuba
    Director of Sales
    Knight's Armament Company
    jleuba@knightarmco.com

  7. #7
    Join Date
    Dec 2006
    Location
    Tennessee
    Posts
    11,762
    Feedback Score
    0
    Quote Originally Posted by Failure2Stop View Post
    M80 out of an 18" tube is going to be around 2600-2700 ft/s, so let's go with 2650 MV.
    You put this into the "Beyond 5.56" rather than the "Other Guns", so I'll assume an AR-based rifle with standard height irons sights, for a 2.6" LOS over bore.
    2" high at 100 yards (basically a 200 meter zero) will give you a max height of 2.25" at 130 yards, POA/POI at about 190-235 (+/1.2") and about 7" low at 300 yards.
    In meters, that's a max height of 2.25" at 120m, POA/POI at 175-215m, and 10" low at 300m.
    Thanks Jack! It is a DD5V4, so yeah, an AR platform. "Neck hold" at 300m should make it just about a COM shot with that data.

    Given that these are standard AR BUIS and aren't quickly adjustable for elevation like an M-14 or an M16A2, I need to pick one "zero" of sorts so it seems like the 200m zero might be the best overall option.

    Primary optic will be a TA-31 ACSS ACOG that can also be used with 7.62NATO (1" high at 100 yards for M80-type ammo or 168gr then the BDC should be close).
    Last edited by ABNAK; 05-18-20 at 17:57.
    11C2P '83-'87
    Airborne Infantry
    F**k China!

  8. #8
    Join Date
    Jun 2009
    Location
    AZ
    Posts
    8,431
    Feedback Score
    9 (100%)
    I do 50/200 or good old 100 yard zero. I always felt if I resorted to my offsets, it would be CQB and it wouldn’t much matter.

    PB
    "Air Force / Policeman / Fireman / Man of God / Friend of mine / R.I.P. Steve Lamy"

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •