How far?


Jan 5, 2021
Vail AZ
I got a real nice Osprey scope. The glass in it is better than some Big Name Brand scopes I have had. The only thing is it has only +-35 MOA of internal adjustment. The RPR it is on has a built in 20 MOA base, and at some point I see myself investing in the Burris rings with the eccentric inserts and I can gain 40 MOA there. Question is, how far do you think I can reach with +- 35 MOA internal adjustment, 10 MOA in the reticle etching and 20 MOA in the rifle?

Which brings me to my next question. Do I need to zero at 100 yards, or would zeronig at a longer distance be more beneficial? When setting up hunting rifles I like the m 3-4" high at 100 yards, but shooting to real distance is a different animal. My first goal is 1000 yards, then working out in stages from there.
I can set targets to 500 meters fairly easily, after that I find myself a nice piece of desert and measure things with the rangefinder. So that is a little slower.
This is on a Ruger Precision in 338 Lapua Magnum.

Now I have the same questions for a DPMS LR-308, except it has zero in the rifle and 70 MOA amount in the scope, which is a Riton 6-24 X5.



PX Member
  • Sep 6, 2006
    Rural Nevada
    35 MOA total internal adjustment? If that’s the case you probably won’t even be able to get down to it 200 yard zero. Nobody’s going to be able to tell you exactly, Get a zero established, punch your load and gun details into JBM, and see what it says.


    PX Member
    Jun 9, 2011
    San Diego, CA
    Sorry to (also) be the bearer of bad news, but that scope is not going to be a good fit for your RPR. As an example, I am running a scope with 110 moa equivalent of internal elevation adjustment on my RPR. While there are no hard rules here, I think a general guideline for success would be to look at scopes that cost a similar amount to your rifle. These are critical, precision instruments that need to survive repeated recoil. Lots of good info in the optics section here on the hide.


    Nov 17, 2020
    Hunter Valley Australia
    I have a couple of cheaper scopes with 17.5 MIL internal adjustment on a 6.5cm and a 338lap, 100 yards is only about 1.5MIL low of centre elevation range on 20MOA base, will still be within scope adjustment on 40 moa base. I have just bought 40MOA bases for both rifles, this will put me close but not on the bottom of elevation adjustment for 100 yard zero and with hand loaded Atips or heavy Bergers and about 6 MIL recticle hold I should be able to hit a mile. The scope you have with 70 internal is slightly more than my scope, should be fine to a mile with appropriate projectiles and recticle hold.

    You probably can't go more than about 30MOA base on the first scope you mentioned with 35 internal for 100 yard zero, should still see you a bit past 1000 yards. If you are happy to zero further out and hold under closer with 35 base it obviously gets you a bit further.

    I find it funny that all these people who are dead set on FFP reticles all of a sudden throw shade on actually using them. A few thousand dollars is a lot of ammunition/loading supplies.
    Last edited:

    Tempest 455

    PX Member
    Mar 4, 2012
    Middle TN
    Ditto on scope. You will need between 70-80 MOA from 100 yard zero with a LM .338 around 2800 FPS (give and take) depending on elevation, temp etc.

    Steel head

    Feral kitten
    PX Member
  • Aug 3, 2014
    That’s a tragic amount of elevation.
    My first long range scope had 65 moa and with a 20 moa rail I had about 50ish moa available. Could dial out to approximately 1400 with my 260.