MOA question

Discussion in 'Long Range Scopes and Other Optics' started by dbleyepatches, Jan 15, 2010.

  1. dbleyepatches

    dbleyepatches Member

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    I am currently in the process of building my first long range prairie dog rifle. I am going to attempt to reach out to the 1000 yard range with this monster.

    The rifle is a 22-250 ackley in a Savage BVSS. I purchased a Burris XTR 6 X 24 scope with 79 MOA of adjustment.

    Now for the question. When I put the rifle information into the various ballistic calculators I find that at 1000 yards the bullet drop should be about 27 MOA with a 300 yard zero (55 grain V-Max, 4000 fps, 0.255 BC). With 79 MOA of adjustment in the scope, I should not need a 20 MOA base at that range right? It looks to me like I should be able to divide the total MOA in half and that should roughly be my up adjustment. With that being said, I should be able to shoot well past 1000 yards with a flat base, I think. I just want to make sure that I am not missing something since this is my first attempt to use target turrets.

    I guess that I should add that I am going to use Burris Z rings so I hope to get the rifle to zero at 300 yards with no or very little internal adjustment.

    Thanks in advance.
     
  2. Broz

    Broz Well-Known Member

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    In a perfect world a scope with 80 moa total should have 40 moa up and 40 down with a zero cant base. I have found this often varies up to 10 moa.

    That being said with your calculations you are correct. But I question the 4000 fps from a 22-250 with a 55 gr. And the ability of it at 1000. My 22-250 with 55 gr Bergers is good enough to shoot a yote at 6 or 700 with no wind. But I can not even get close to 4000 fps even with a 26" tube.

    Jeff
     
  3. dbleyepatches

    dbleyepatches Member

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    When I contacted Hodgdon about load data for the 22-250 ackley they said that Ackley recommended using the load data from the 220 swift. I used 4000 fps in the calculation because a friend of mine has a 220 swift that will chronograph 4020 fps with no pressure problems out of a 26 inch barrel. I am not saying that my gun will do this, we will have to see.

    I am not planning on shooting coyotes with this gun out to 1000 just prairie dogs. This gun might not be able to reach out that far even on prairie dogs but I plan on pushing the limits. At 1000 yards it should have something like 130 ft/lbs of energy (according to the calculator).

    Thanks for the response, with the Burris Z rings I should have more adjustment than I have rifle! With this being my first attempt at shooting long range and using the turrets I am relying mainly on ballistic calculators and MOA charts instead of experience, which can be dangerous!

    Thanks again.
     
  4. Broz

    Broz Well-Known Member

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    Sorry, I missed the Ackley part... My bad. I am sure you will have plenty of energy to do a pd at 1000 if you can connect. Let us know how she groups at 1000 if you would.

    Thanks

    Jeff
     
  5. Broz

    Broz Well-Known Member

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    Thought you might enjoy this. We did mangage to connect with a gopher at 1002 yards and catch it on video. Even after taking a hit in the rear from a 300 SMK he managed to crawl off. One tuff little guy..:D gun)gun)



    YouTube - 1000 gopher.wmv

    Jeff
     
  6. 4xforfun

    4xforfun Well-Known Member

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    Get the 20 MOA base....then you will know for sure. You won't have any problems at short range and you can get out there with no problems. I question the 55 gr bullet. If you are building from scratch, go with a little faster twist. You can still shoot the lighter bullets, but you will also be able to run with bullets better suited to LR.

    That is just me, so take it for what it is worth.
     
  7. dbleyepatches

    dbleyepatches Member

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    I totally agree with what you are saying. I am having the factory barrel (1 in 12 twist) reamed to Ackley Improved and I am going to use it until it is shot out. Then I am going to a little faster twist and either 28 or 29 inchs :). That should really make her scream!

    I might try the flat base and the signature rings with the offset inserts at first since I have that stuff laying around. Anyone ever use the Weaver Tactical one-piece base before?
     
  8. dbleyepatches

    dbleyepatches Member

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    That is an awesome video! I hope to have some shots like that in the future. After I get the 22-250 all outfitted and I get the "fun money" account built back up, I want to build a longrange hunting rifle. I can't decide on a caliber yet, but something to reach out and smack an antelope!

    Nice Shot!!
     
  9. Broz

    Broz Well-Known Member

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  10. Ridge Runner

    Ridge Runner Well-Known Member

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    remember this in the world of long range, BC outruns velocity

    I'd go 8 twist and use a 69 gr smk or 75-80 gr a-max, you wouldn't need a 20 moa rail then.
    RR