Printable View
Hi I just want some help to check if I'm doing this right, I sighted in a new scope and zeroed it at 200yds bullet dropped 10inch at 300, 32inch at 400, and 62inch at 500yds, now here is my prob, 500yds is 5 moa, 62 divide by 5 is 12 so I should adjust 12 moa is this correct? Because when I do this I was shooting well over the target I had to adjust back to 9 moa to hit the target and could not make sense of it, calibre is 308 scope is leupold mark 4 LR/T 8-25, any help would be appreciated
If it drops 5moa dont you rise it 5moa?
I actually have no idea but if something dropped 5moa I'd think you have to rise the sight 5moa to bring it back to zero.
I'll go away now and leave it for someone in the know :D
You now know its 9 MOA to hit a target at 500yds so whats the problem? apart from being like me and not understanding the math of it all I just rely on shooter and validation.There will be some number crunching wiz along shortly hold tight.
That's a lot of drop. I would be rechecking the 200yd zero. Even at 2600fps .308win should low fiftys for drop at 500yd with 200yd zero.
What load are you using? Have you choreographed it?
Yes 1moa = roughly 5 inches at 500 yards, so *if* you have 62 inches of drop it *should* be about 12.5moa of up to hit at 500.
Balkie, the easiest way to do that calc is to ask : what is 1 MOA at this distance ?
So at 500yds, 1 MOA is roughly 5 inches.
If your correction is 62 inches, then divide 62 by 5 = 12.4
Did you get the 62 inches from a balistics chart /program, or was it an actual measurement based on shooting 500yds ?
Several things can be happening:
Your range estimate might be incorrect
Your input variables to the ballistics calc might be incorrect
The click adjustments on your scope might be inaccurate
I did recheck the zero again before I finished, I thought it was a fair bit of drop also, rifle is suppressed but removed that and was still shooting the same groups, was shooting with federal fusion 180gr
A MOA is not exactly One inch at 100y,also your scope may not adjust exactly 1MOA for one MOA adjustment.
As neckshot said now you know its not a problem.
And that is a hell of a lot of drop! running 208s-215s? I get a muzzle vel around 2500fps
Did some one cut it in half before fitting the suppressor?Quote:
Originally Posted by superbalkie
I hope that was an autocorrect mistake! :PQuote:
Originally Posted by gimp
I had a range finder so distance was good and the 62inch was from testing not from chart, I would hope the scope is set right it not exactly a cheap and nasty scope
haha yesQuote:
Originally Posted by Spudattack
Are you using the drop chart on the side of the ammo packet or have you calculated the 62"? Seems an awful lot and probably where the error is coming in.
2750fps is a rough guess if you came up 9 moa at 500 yds for 180gn projectile
Rifle is steyr scout which is fairly short barrel may explain a little more drop
So just to be clear, you zeroed at 200yds, did not change the elevation setting, shot at a target @ 500yds, and got impact 62 low ?
Range finders can be inaccurate as well :D sure it was set to yds not meters ?
at 2600fps you must of zeroed at 100 ?
meh this is why I don't worry to much. shoot five shots at 500yds if you hit the target 5 times with 9 moa move on to the next problem
Problem is his measured drop was 62" or roughly 11.75 moaQuote:
Originally Posted by Neckshot
yes my head is sore now!! I don't care:DQuote:
Originally Posted by veitnamcam
Where are you could be gravity? 5'-0" is nearly a lob shot:)
Can't help with the moa,mines stashed under the house:yaeh am not durnk:
I am with Neckshot on this. If you know that nine moa gets a hit at 500 then problem solved. The why becomes somewhat irrelevant.
Any kind of bullet drop compensation that's based on guess work is hopeless.
all inputs need to be correct in order for you to get any kind of workable drop chart.
Knowing how fast the given projectiles are going is very important.
If you can't get hold of a chrono re-write your chart in the field based on actual drop and Click value required at given ranges.
This will take some considerable time and precision shooting but it does take away the effect of any variables you may have in your set up.
Cheers.
If indeed your drop is measured and your zero is 200 you should get something like this , not perfect match but i didnt have time to tweak , but it would seem a very low velocity .
http://i669.photobucket.com/albums/v...album/drop.jpg
If then you adjust your scope and find that it only takes 9 MOA to reach your target i would then look at the scope adjustments , they cant be tracking 1/4MOA . It can be corrected in a ballistic program to match your scopes actual tracking adustments but i would suggest more varified testing first.
So you still havent told us if you have measured the speed at all?Quote:
Originally Posted by superbalkie
Moa help?,
Sorry, too late, moaris ate them all already.