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Thread: MPBR Zero and the Civilian AR

  1. #1
    Supporting Business NH Shooter's Avatar
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    Sep 2014
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    MPBR Zero and the Civilian AR

    As many of you know, I'm running a somewhat unique optic setup on my carbine - the Leupold FX-II Ultralight 2.5x20mm in a Daniel Defense mount;




    My main attraction to this set up is light weight (12 ounces total), generous eye relief and a very streamlined, snag-free profile. My eyes also appreciate the excellent clarity of this scope, enabling me to see the target far more clearly than I could with a RDS or irons. The long eye relief and generous eye box works very well with both eyes open, and makes acquiring the target almost RDS quick. The petite size of the scope occludes only a very small part of the view compared to larger scopes (especially those with with large turrets and shorter eye relief).

    Since the (sharply-focused) duplex recticle has no stadia lines, ranging is out of the question. For that reason, I am treating it like a RDS and using the maximum-point-blank-range zero technique.

    For my go-to load of choice, the Speer LE .223 75-grain Gold Dot, I ended up with a 230-yard MPB range with a trajectory that does not exceed 2-inches from the line of sight. Though this sounds a bit too precise, I also decided to factor in the inherent precision of this load in my rifle, which is typically slightly better than 1.5 MOA. With that factored in, the trajectory opens up to a potential 3.5" deviation from the line of sight out to 230 yards, or aiming dead center out to that range and staying within a 7-inch circle (assuming I do my part).

    Since my carbine is intended for defensive purposes, I believe 230 yards is more than adequate. In my neck of the woods shots longer than that are the exception, not the rule due to the landscape. That said, if a longer engagement is called for the following easy-to-remember hold-overs can be applied based on the size of the target;

    • 300 yards - 10-inches
    • 350 yards - 15-inches
    • 400 yards - 30-inches

    When it comes to a defensive long gun, I greatly prefer simplicity. The MPBR zero technique certainly contributes to that goal. This rifle is truly point-and-shoot out to 230 yards, which fits my simple-is-better preference nicely.

  2. #2
    Site Supporter entropy's Avatar
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    Surprised no comments yet. Good thread for discussion. I did the same exact thing using mine set up for 75gr PPU Match and PA glass. I wanted a load which was relatively inexpensive and effective without going the handload route. The data was run thru Ballistic, printed out, laminated, and stored in the pistol grip. Simple is good. I’ve used this very method on all my defensive rifles and PDWs.
    Working diligently to enlarge my group size.

  3. #3
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    NOT surprised on the lack of responses. Many of us here use and teach the 50/200 zero. 50 yards on the way up, 200 (actually closer to 212-220) on the descending arc. All shots within 3.1 inches POA/POI depending on sights used. Shot this zero out to 717 meters with iron sights. Approx 9 inch drop at 300....qualified just this week with this zero...

    In class we zero at 50, then test out to 200+

    pat

  4. #4
    Gucci gear, Walmart skill Darth_Uno's Avatar
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    I too prefer KISS. This is a very appealing setup to me.

    A few years before LPVO’s took off, I saw a guy running a pretty basic 3x shotgun scope on his AR. He described it a poor man’s ACOG, before there were really any other viable prism scopes on the market. I thought that was a great idea. Looks like your concept is pretty similar in function.

  5. #5
    I've used the 100 meter zero for years after reading this thread written by @Failure2Stop many years ago.

    https://www.m4carbine.net/showthread...100-Meter-Zero

  6. #6
    Member
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    May 2011
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    Pittsburg, KS
    Quote Originally Posted by NH Shooter View Post
    As many of you know, I'm running a somewhat unique optic setup on my carbine - the Leupold FX-II Ultralight 2.5x20mm in a Daniel Defense mount;




    My main attraction to this set up is light weight (12 ounces total), generous eye relief and a very streamlined, snag-free profile. My eyes also appreciate the excellent clarity of this scope, enabling me to see the target far more clearly than I could with a RDS or irons. The long eye relief and generous eye box works very well with both eyes open, and makes acquiring the target almost RDS quick. The petite size of the scope occludes only a very small part of the view compared to larger scopes (especially those with with large turrets and shorter eye relief).

    Since the (sharply-focused) duplex recticle has no stadia lines, ranging is out of the question. For that reason, I am treating it like a RDS and using the maximum-point-blank-range zero technique.

    For my go-to load of choice, the Speer LE .223 75-grain Gold Dot, I ended up with a 230-yard MPB range with a trajectory that does not exceed 2-inches from the line of sight. Though this sounds a bit too precise, I also decided to factor in the inherent precision of this load in my rifle, which is typically slightly better than 1.5 MOA. With that factored in, the trajectory opens up to a potential 3.5" deviation from the line of sight out to 230 yards, or aiming dead center out to that range and staying within a 7-inch circle (assuming I do my part).

    Since my carbine is intended for defensive purposes, I believe 230 yards is more than adequate. In my neck of the woods shots longer than that are the exception, not the rule due to the landscape. That said, if a longer engagement is called for the following easy-to-remember hold-overs can be applied based on the size of the target;

    • 300 yards - 10-inches
    • 350 yards - 15-inches
    • 400 yards - 30-inches

    When it comes to a defensive long gun, I greatly prefer simplicity. The MPBR zero technique certainly contributes to that goal. This rifle is truly point-and-shoot out to 230 yards, which fits my simple-is-better preference nicely.
    There's a reason the 50/200 yard zero is so popular and this is it. You're just calling it MPBR. From 0 to 215/220'ish you're never more than 2" away from POA.

  7. #7
    Supporting Business NH Shooter's Avatar
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    Hit the range today to verify the MPBR zero.

    This rifle very much likes the Speer LE .223 75 Gold Dot load, which I've known for a while. I shot at 200 and 300 yards from the prone on bags for my session today.

    What I found is that this rifle/load combo will regularly create a near-MOA cluster then send one flying out of the group. It seems to consistently do this, but even with the flyers the groups stay around 3 MOA.

    Here is a target I shot at 300 yards - five shots in a 4-inch cluster and a flyer low, holding at the shoulders to account for the 9-inch drop. I'd really like to figure out what's causing the flyers, but still not bad for a lightweight rifle with a 2.2x fixed optic;


  8. #8
    Site Supporter JSGlock34's Avatar
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    Feb 2011
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    USA
    I tend to favor 50/200 as a 50 yard range is typically the maximum I have available, and I think it well covers any realistic use of the carbine, and is much superior to the 25/300.

    That said, I took a Vickers Tactical class many moons ago, and I found his explanation of the 100M zero quite compelling, and I've used the 100M zero in the past. Unfortunately 100M ranges aren't very convenient for me.

    I dislike hold-unders; the 50/200 minimizes rise and the 100M eliminates rise as the round should never rise above the point of aim. Hold overs only come into play past 200M.
    "When the phone rang, Parker was in the garage, killing a man."

  9. #9
    Member SecondsCount's Avatar
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    Feb 2011
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    Utah, USA
    I do a 100 yard zero with all my scoped rifles just for pure consistency. Red dots and open sights get zeroed at 25.

    If I put the 75 GD into Strelok, using a 100 yard zero, this is what it comes up. This is why I love 5.56. Plenty of energy and the velocity keeps it flat.

    Name:  Screenshot_20200907-161528_Strelok Pro.jpg
Views: 1018
Size:  57.9 KB
    -Seconds Count. Misses Don't-

  10. #10
    Quote Originally Posted by NH Shooter View Post
    Hit the range today to verify the MPBR zero.

    This rifle very much likes the Speer LE .223 75 Gold Dot load, which I've known for a while. I shot at 200 and 300 yards from the prone on bags for my session today.

    What I found is that this rifle/load combo will regularly create a near-MOA cluster then send one flying out of the group. It seems to consistently do this, but even with the flyers the groups stay around 3 MOA.

    Here is a target I shot at 300 yards - five shots in a 4-inch cluster and a flyer low, holding at the shoulders to account for the 9-inch drop. I'd really like to figure out what's causing the flyers, but still not bad for a lightweight rifle with a 2.2x fixed optic;

    Is the flyer the first round stripped from bolt release, and the grouped rounds feeding after?
    It doesn’t have to be fun to be fun ― Mark Twight

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