Question on burris signature ring inserts

[NDAR15MAN]

I have a set of the burris signature scope rings with the plastic inserts to give you more up and down travel. I have always been a hunter and really never used my scope turrets to make long range cross hair adjustments. I always just Kentucky Windage the bullet drop. Will know with my me 6.5 Creedmoor I am putting a 20 moa scope rail on it. So my question.... When I do ad the 20 moa rail and and burris signature rings or any type of ring does that change the come moa numbers that are printed out on these ballistic calculator information sheets ? Like I have a ballistic chart that says at 600 yards the come up on a 140 gr A-max is 10.5 moa. With adding the 20 moa rail change this number if I just dial this number on scope ? Just wondering if every thing stays the same on turret with a 20 moa rail. Thanks

 

[jimbires]

the 20 MOA rail should not change your correction amounts . just mount the scope and zero it at the same distance as you were zeroed at before . everything should work out to match your drop chart . I'd be cautious using a 20 moa rail and also the burris rings . you can add enough tilt to your scope that you will not be able to get your zero before the scope runs out of adjustment .

 

[GrocMax]

The inserts are marked in thousandths, simple trig sez with the scope mounts 4" apart two sets of 010 inserts can add or subtract approx. 20 MOA.

 

[NDAR15MAN]

Grocmax. Thanks for your help but I know how the rings work and how to install them. My question is about the effect on the turrets when I dial the turret. Up or down. Does the number on the turret change at all because of having a 20 moa rail ? Marty

 

[BoydAllen]

No it does not as long as you are talking about come ups from a standard zero. If, after you install the base and rings, the rifle is re-zeroed to the same distance that your come ups were figured from everything will be as good as your source of information. Essentially what you are doing with scope tilt is to increase the amount of available adjustment in the up direction from where you are initially zeroed, and decrease the amount below it.

 

[NDAR15MAN]

Great. Thanks for your answer. Really big thanks to every one help us newbies. Marty

 

[Jeff A]

A couple of things. First, do the rail or the rings, not both. My Signature rings are marked with MOA, not thousandths. Just using the rings, I put a 10 MOA cant and I have a lot more adjustment than I need to shoot at 1000 yards with a 6.5x47 Lapua. Have fun!

 

[NDAR15MAN]

Will do. Marty

 

[BoydAllen]

On the signature rings, the angle created by the offset depends on the center to center spacing of the rings. You can figure this out by solving a simple ratio problem, putting the amount of change you want at 100 yards in inches over 3600 inches equal to x (the offset of a single ring) over the center to center ring spacing. By cross multiplying you can solve for x and get the number of thousandths offset required. If you are not going to put in any windage you will have to pick the closest set or combination available, and do the rest with your scope's internal adjustments. I start with sets of centered inserts, and the scope set with its reticle centered, determine how many inches I am off both in windage and elevation and then convert that into inches at 100 yards. I usually do the testing at 50 to make it more likely that the bullet hole will be on the paper. From there I can figure out what inserts to use, including how I might want to rotate them so that I can center from side to side. For shorter range applications where my scope can handle the distance adjustments, I try to set the rings so that with the scope adjustments centered that I am close to zeroed at 100 yards. It takes a little trig to come up with the vertical and horizontal effect at different points of rotation between zero and ninety degrees. Back in the day, I made up a chart showing what the results were for every fifteen degrees of rotation.