Where am I screwing up. sako 30-06 is having issues passed 500

[Boomer81]

I'm hand loading .208 a max 58grains rl22 3.34 coal. Win large primer win brass new. It's a 1/11 twist but idk if it's right hand or left and can't find any info. And I'm getting pulls way right. I'm dialing right as for my dope and real-time app. Im shooting off bags. My follow through feels dead on. But the thing curveballs right. at 800-1000. Elevation is tracking as it should. This gun is easily half moa if not better. I've had a half moa 10 shot string once with it. Which is great considering bullet size.its the Sako a7 roughtech Talley bases viper pst Leupold tactical rings. I got to thinking last night I may have the wrong twist data entered in my app. Any info will help

 

[jpd676]

So, you are getting 1/2 moa groups but they are right of where they should be? What elevation are you shooting at? How far is "way right?" I shoot the 208 in several calibers and it has been great for me.

 

[Hand Skills]

https://loadoutroom.com/13415/reaper-tips-spin-drift-coriolis-effect/

I believe Sakos are right-twisted (punny?), so spin drift is likely a factor.

A lot of guys these days are using electronic firing solutions (like a ballistics app such as Applied Ballistics) on their phone or PDA.

Keeping track of all the variables manually is quite a challenge, and will help in the appreciation of a good firing solution!

 

[Boomer81]

a couple yards to the right. man sized steel torso's at 800 and 1000 what got me thinking. it's closer when i don't even dial any windage. but it's still right. something is off with me or data entered into the app. elevation is 1500 the weather has been in the 50's ill put a camera on me and see if im pulling. i have 3 weeks until holiday gun season opens back up. so im gonna tear it down put it back together. trying to make a doe kill in that range.

 

[big_matt_duq]

Is the scope level? That seems like a lot though.

 

[Adikted]

I'm sorry to anwer a question with a question. What ranges have you doped it out at? There's a lot that could be going on, if it's off a couple of yards I'm betting that your scope is either mounted slightly canted or you are canting it slightly due to the changes in the horizon from one target to another. If it was just spin drift then you should be seeing it at 600 + not just all of a sudden at 800, plus spin drift alone shouldn't move you 6 feet at a thousand.

Also, does the elevation change a lot at your range? If your zero target is down hill and your 1000 yard target is up the next hill you could be getting wind drift that you can't perceive.

 

[Barrelnut]

You need to test your scope with a tall target test. Need to make sure that the POI is not moving right as you dial up. It's easy to do. Sometimes you need to eliminate variables to come to a conclusion. You could have a scope with POI moving right at long distance and spin drift. All bad juju.

 

[Don A Parsons]

I agree, the tall target test is easy to do.

Ones you complete that it might be wize to shot a box.

Start with Bulls Eye, then adjust optics according to make a four shot box, confirm center shot zero once your done.

If your rifle has a optic bubble and is truely level on all shots, the box should be square and level.

Check with a carpenters level to confirm, the up and down sides of your box strait up and down as well.

Western Canada Don.

 

[Boomer81]

all of the above down hill 100 zero up hill 1000. Yep I have that **** dvd and was thinking that thanks guys. I own I watched it just have not done it. Bought. Level need to get that on as well. It's all in the details. Thanks folks

 

[WildRose]

You probably need one of these and a bubble level to go on top of your scope as well for the fine tuning.
https://www.longrangehunting.com/store/segway-reticle-leveler.html

Even just a couple of degrees off of plum adds up to a large error at 800-1000.

Once your reticle is plum to the bore install a scope level to keep yourself plum/level when shooting.

 

[FatBoy...]

I agree a tall target and box test should be the next step. If the scope passes than maybe try a lighter bullet. Maybe something in the 185gr range? 11 twist seems a bit slow for 200+gr bullets and 208s are long. It would be very odd than an unstable bullet would fall right every time, but who knows without testing another weight.

 

[Canhunter35]

The first step is get the bubble level mounted and plumb. I'm betting that'll take care of ur problem. If ur right handed, when you tilt ur head to lay ur cheek on the stock, it makes you want to tilt your gun to the the right, cause it looks level but it's not

 

[Adikted]

I agree a tall target and box test should be the next step. If the scope passes than maybe try a lighter bullet. Maybe something in the 185gr range? 11 twist seems a bit slow for 200+gr bullets and 208s are long. It would be very odd than an unstable bullet would fall right every time, but who knows without testing another weight.

A bullets rotations per second (think stabilizing force) doesn't decelerate much in the short time a bullet is in the air. The velocity (think destabilizing force) however does. Typically if a bullet groups well at 200 yards it will be good though it's entire flight.

Usually when a group opens up at distance it because the bullet is transonic at some point in the flight. 208grs from a 308 are usually supersonic to 1000. 30-06 should be fine