off by 2 moa at 500

[SOUTHTEXASBOY]

-Have you done a tall test on your scope to test your turret accuracy?
-Verified the accuracy of your 200 yard zero with precisely measured 300 and 500 yard testing from the same shooting position?.

 

[snookntarpon]

Thanks for all your replies.BC was a typo and does not make that much of a difference. Yes. 2.89

I am going to shoot a 100 yard target as well and re-verify the 200 even though I feel very confident it was zeroed, but a little doubt means i need to check again.

Will follow up in a week or two with findings. Thanks
SnT

 

[coop2564]

I would think the 1 fps spread over 5 shots should tell you something was wrong the magnetospeed. Also did you compare the drops with the Sig 2400 vs a shooting app. I had some issues with sig 2400 and I switched to the 2200 and use a kestrel. Now I never question the data I get.

This! 1fps for factory? Not likely.

 

[snookntarpon]

did a string of 3 on the magneto (3" high at 200 with magneto on barrel but dead center still). shot 20 rounds for moa without magneto, verified speed with last 2 rounds as I was suspicious as well. image below

 

[Wanfalt1]

I have never in my experience had a ballistic download fit my comeups perfectly. I want to say this with all due respect. I quit using a chronograph. Too much to lug around. I have used a real old ballistic program for years. But the program was great for what I used it for. The 7/08 is an over achiever so you can't go wrong there. If your inputs are correct. Scope Height, caliber, bc,. Start to manipulate your numbers . At Sea level they won't be very impressive. But "they is what they is." be skeptical and you won't be disappointed. Shoot 100,200,300 and interpolate from there. I always seem to be changing velocity. At 7200 feet above sea level, you get stellar numbers. If I were to come down to sea level it might get depressing. I always have a ballpark of what my velocity should be. BUT the drops tell the story. Trust your actual impacts. Document them and manipulate the numbers. Accept them and prove them. You will be content when you accept them. My experience was frustrating until I decided they are what they are. Hope this helps. I always wanted them to be small. Be realistic and you won't be disappointed!

 

[Trm82]

User error is the first thing that comes to mind.

How are you measuring scope height?

Are you sure your parallax adjustment is correct?

Are you shooting from the same position ie bench, prone etc when both zeroing and shooting the 500 yds target?

Next would be checking your inputs, specifically the BC. Are you using G1 or G7 BC in your calculation?

Is your program set for running manual inputs for atmospherics or station pressure data?

If your inputs are correct try switching and using the G1 BC and see if it gets you closer to accurate.

I have shot to 1000 yards with my scopes that give me the elevation to do it and never measured scope height. Scope height is not your problem.

 

[Joefrazell]

#1 I think your magneto speed may have had an error. #2 do a tall target test to make sure your scope is tracking correctly. #3 be sure your adjusting for parralax correctly.

 

[WildRose]

I have shot to 1000 yards with my scopes that give me the elevation to do it and never measured scope height. Scope height is not your problem.

What ballistics program are you using that doesn't require scope height as part of the inputs needed for a shooting solution?

 

[4xforfun]

OK...for those of you thinking that scope height is the problem, consider this:

Using the same balistic and enviromental input data for both of the following scope heights....162 Amax (Sierra I6 doesn't list the ELD-X) @ 2700 fps, 0 elevation, 200 yard zero, 29.xx PSI.... impacts at 500 yards:

with 1.5 inch scope height....8.5 moa low at 500
with 2.5 inch scope height....8.2 moa low at 500

That is a .3 moa difference.

It may be a factor, but a small one, as it would be almost impossable to be off by 40% on your scope height measurement.

Tod

 

[WildRose]

OK...for those of you thinking that scope height is the problem, consider this:

Using the same balistic and enviromental input data for both of the following scope heights....162 Amax (Sierra I6 doesn't list the ELD-X) @ 2700 fps, 0 elevation, 200 yard zero, 29.xx PSI.... impacts at 500 yards:

with 1.5 inch scope height....8.5 moa low at 500
with 2.5 inch scope height....8.2 moa low at 500

That is a .3 moa difference.

It may be a factor, but a small one, as it would be almost impossable to be off by 40% on your scope height measurement.

Tod

An accumulation of errors is more often than not the problem in ballistic solutions rather than a single input which is why all have to be examined when trying to solve a problem.

 

[jrsolocam]

1. Snug base/ring screws.
2. Verify zero.
3. Conduct tracking test.

If this pans out it I'm at a loss. All the ballistic programs are reasonably close to each other.

 

[Adikted]

I'm not sure which version of the magnetospeed you are using but I've had mine read off if the sensor isn't spaced correctly from the bore line, the higher end version used to come with a square bar to check it, not sure if they still do...

 

[4xforfun]

An accumulation of errors is more often than not the problem in ballistic solutions rather than a single input which is why all have to be examined when trying to solve a problem.

So, we agree....Great minds DO think alike!!

Tod

 

[WildRose]

So, we agree....Great minds DO think alike!!

Tod

Never said otherwise. That's why I originally posted a list of questions relating to various things that could be contributing to the error.