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Old 06-18-2012, 11:16 PM   #11
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Ribbs,

First of all if you are zeroed at 100 yards with the 55 gr. American Eagle rounds FMJs you should automatically have about 2.7-3.0 inch drop at 200 yards. I am going to continue but understand that my thoughts are not to challenge your ability at all but to try to dissect the problem.
First have you benched the rifle and used bags or a support to sight it in from the rest at 100. Your rifle should be able to get at least 1.5 MOA (Inch) groups at 100 yards with the American Eagle ammunition. Of course if the group is an inch and a half spread at 100 it will be magnified at 200 way more than twice the spread. As far as 5 inches off at 200 lets think about the WIND! That realy effects the 223 round. If you have a 10 mile an hour full value (Cross wind at 90 Degrees) it will move the round off to the opposite side of the wind around 2 to 2 1/2 inches at 100 yards. So imagine what the effects of the wind at 200. 5 inches as you mentioned is nothing if you consider the wind mentioned. That might put that to rest? As far as the 8 inches low unfortunately that is not the fact that your rifle has the 1 in 8 twist. It would not effect it that much. In fact a 1 in 8 although they like slightly heavier rounds best seemingly would not have a drop of 8 inches. I would suggest you bench or support the rifle on a solid surface and bags at 200 to check and do it on a calm day. Things like trigger pull, breathing and a slight flinch could cause drastic results at 200. You will know if you bench it and practice good trigger pull and do not breathe when pulling the trigger. If the rifle is shooting great at 100 there is no problem with the ammunition or your rifle. Oh by the way are you using a scope or optic that could have some parallax problems. The delayed breathing technique when pulling the trigger to shoot is called the natural pause! Just suggestions and good luck.
All the above information is pending the good performance at 100 yards!
03

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Old 06-18-2012, 11:17 PM   #12
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how did you zero? 100 yards? 50? 25?

are your rounds keyholing?

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Old 06-18-2012, 11:48 PM   #13
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Ribs...lots of good thoughts here. One other, how experienced are you? Shooting 250+ yards is an order of magnitude harder than 100-150. As stated, every minor error you make on trigger pull, breathing, sighting, etc is really magnified at higher ranges. Wind and bullet weight become important as well.

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Old 06-19-2012, 12:44 AM   #14
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Yea i would consider my self a fairly good shot been shooting bolt action all my life with plenty of sighting in experience with BOLTS . I am shooting 1.5 at 100'and 2moa At 200 I'm using beanbags and a stand on a solid table. The wind was 10 to 15 today I can't explain the huge difference between 150 and 200 . And it will shoot to the same low right spot consistently not all over the place

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Old 06-19-2012, 01:28 AM   #15
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As Doc posted zero 2"+ AT 100 YDS. This will give you a point blank to 250 yds. When you zero at 100 yards all rounds will fall below the parabolic line of trajectory beyond the 100 yd. mark. The line of sight should be high at 100 yds.

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Old 06-19-2012, 04:46 AM   #16
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Quote:
Originally Posted by Durangokid View Post
As Doc posted zero 2"+ AT 100 YDS. This will give you a point blank to 250 yds. When you zero at 100 yards all rounds will fall below the parabolic line of trajectory beyond the 100 yd. mark. The line of sight should be high at 100 yds.
This is very true. Or you can zero at 50 yards which will keep you within 2.5" of POA from 0 to about 250 yards.
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Old 06-19-2012, 01:16 PM   #17
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First, I'd get some good factory ammunition and see how your groups look, and then worry about sighting in. I doubt there's anything wrong with your barrel, and 1:8 should be fine with 55 grain ammo.

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