6.5x284 can not figure why i am 2 MOA high

[Magwa]

So I am shooting a 6.5x284 Norma Lapua Brass fed 210 primers and 48 and 1/2 grains of H4350 out of a 26 inch proof research barrel 1 in 8 on a Remington long action. I am shooting Berger 140 Grain target Hybrids at 2950 (with magneto speed) seated to 2.460to the Ogive and a OAL of 3.165 20 K off the lands. I am using a sig kilo 2400 ABS range finder and applied ballistics that comes with it the load shoots .33 at 100 yards and i have zero trouble out to 400 yards but after that things get sketchy say at 600 I range and it tells me up 10.5 ok i am a full moa high and have to dial down to 9 MOA to make a good hit on target then at 850 i dial18.1 and have to dial down 2 full MOA to 16.1 to hit. so I true my MV and it says I am shooting 3134 which I know can not be right I am totally befuddled by this any ideas or help is appreciated... thanks

more info 2500 altitude 60 degrees Humidity 38%

 

[Aftermath]

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Basically, your DOPE is good to 400 then falls apart. What has been suggested to do is to now adjust your BC for those farther ranges until the actual dope fits again.

 

[Magwa]

sounds reasonable, now i just have to find out how to do it....

 

[AIAW]

If you have verified MV with a chrono then use that, don’t fudge the MV just to match the trajectory otherwise it’s all going to be off. Make sure you have a dead-nuts zero also.

Like Aftermath said, go for adjusting the BC.

I don’t own a Kilo, but there should be a way (like the other AB devices) to adjust the BC. A higher BC input will force the computed trajectory lower, whereas a lower BC input will force the computed trajectory higher. Ideally you’d do this POI testing right before transonic range also if you have the distance available.

 

[Aftermath]

One other thing, verify that the center of bore to center of scope is right on the money, that you input into the ballistic calculator. This is not real hard to do if you use a set of calipers to measure bolt diameter (divide by 2) add scope diameter (divide by 2) add the gap between them.

 

[st1650]

One other thing, verify that the center of bore to center of scope is right on the money, that you input into the ballistic calculator. This is not real hard to do if you use a set of calipers to measure bolt diameter (divide by 2) add scope diameter (divide by 2) add the gap between them.

Would that really make up a 2moa (ie approx 16" @ 800 yards)

 

[Magwa]

ok this will be funny but it worked, last week i checked zero it was GTG so i went to a shoot and I was almost 100% consistently off 2 MOA at all ranges from 400 to 1320 so i just back the zero stop screws out lifted the know and went down 2 MOA and put is back on I shot the 15 round course again and was spot on with all my ups, that did not stop me from dialing the wrong windage right when i should have dialed left but those were the only ones i missed. I am thinking my scope may have a issue will check on that this week and do a ladder test thank you all for the information I am learning just painfully slow...lol

 

[MarkyMark007]

first of first check clicks on riflescope. most of them are NOT what they claim to be: 1 MOA on the riflescope may NOT be 1 MOA on real paper.
like tests on snipershide how almost all riflescopes track perfect... TOTAL LIE !

next: bullet's BC vary from rifle to rifle.

 

[JustSendit]

That’s a pretty big BC shift and MV. Confirm you’re using the correct custom curve or G1/G7 BC. Of course the zero must be good as well.

Do a good look over all of your inputs and confirm they’re accurate. If everything lines up, and you have a good zero, maybe try a box or scope tracking test. It happens occasionally scopes track poorly.

Little variants like zero range off by a few yds and height over bore being with 1/2in will see a minor change in data at 1000yds.

You’re looking for something big, like you have a 140eldx BC input not Hybrid Target, not a small 500da shift, or twist rate that incorrect.

 

[Magwa]

sorry I did not get back to this we have had some major health issues with loved ones and everything just took a backseat . anyway thanks for the reply i am baffled by it but it was a consistent 2 MOA but it is shooting with the Sig Kilo 2400ABS spot on now with the berger 140 Hybrids... again thank you all for the help.