How much MOA in a scope needed?

[walkabout]

If I needed a rifle in 6.5 x 47 Lapua to be zeroed at 100 yds, but be able to reach 1000 yds would a scope with only 55 vertical MOA adjustment with a 20 or 30 MOA rail be viable?

 

Mark

[The Gun Pimp]

With the 20MOA rail it should be OK for 1000 yards.

 

Your 55 MOA would be reduced to 27 MOA or thereabouts when mounted and when zeroed at 100 yds you'd maybe have 20 MOA left - but you could then 'capture' another 20MOA with the tapered rail - which should be enough for 1000 yards.

[Cheetor]

Mark, Tbis may or may answer your question, with a velocity of say 2900fps and a scope height over bore of 2" with a 0moa rail you would need approx 29moa to reach 1000yrds with a 123gn lapua scenar, not exact but a reference to start from.

If your 100yrd zero was achieved at the mechanical zero of your scope, you would have 27moa (assuming 55moa is total adjustment + and -) which would require you to hold off. Probably not a good thing to try to use any scope at fuĺl elevation or windage adjustment.

A 20moa rail would allow the use of some of the lost moa that would never be used at 100yrd zero.

Broadly speaking with nothing changing other than the fitment of a 20moa rail you will easily reach out to 1000yrds, if clearance was an issue or you did not want to raise the centre line of the scope with higher rings a lower moa rail could also work maybe 10 or 15moa.

If you are feeling handy you could always bed your existing rail to achieve the same. Bragging rights are obviously increased with a 20moa rail more so with a 30, whether you need it or not is a different thing

Just my opinion which may be totally wrong!

[Leeman]

Mark,

 

Using 130 grain Norma's I need 22.5 from 300 to 1000, so figure another 3 to get you to 100, It's definitely doable. If you use Burris Signature rings you could steal approx another 20MOA at the very least using ten thou inserts in both rings if using 30mm rings and upto 40 with 1 inch rings.

 

Richard.

[jcampbellsmith]

Mark,

 

Using 130 grain Norma's I need 22.5 from 300 to 1000, so figure another 3 to get you to 100, It's definitely doable. If you use Burris Signature rings you could steal approx another 20MOA at the very least using ten thou inserts in both rings if using 30mm rings and upto 40 with 1 inch rings.

 

Richard.

Burris Signature rings are definitely a help, however one set of inserts might end up being used on centering the scope right to left. I'd suggest getting a couple of sets of Burris Signature rings and picking 2 rings out of 4 to give you a better set of options.

 

Secondly getting within 5 MOA horizontally or vertically of the mechanical centre of your scope is a lottery with any rings, let alone the Burris Signature Rings. You could try setting your 100 yd zero about 15 MOA up from the bottom of your scope adjustment?

 

Regards

 

JCS