Scope Base Size

[Nelius88]

Hello friends,
I have a Ruger American Hunter I am setting up for precision long range. It comes with a 00 moa scope base. I have a Vortex Viper PST on Vortex 1.26 inch precision rings. In order to make 1000 yard shots would it be necessary to replace the 00 moa scope base with a 20 moa scope base even with the higher precision rings? Thanks for the help.

 

[ColinW]

A 20 MOA base is always nice to have! In that kind of circumstance, It's better to have it and not need it than to need it and not have it I don't believe the ring height will make any difference other than clearance for your scope objective over the base and barrel. If it works on your flat base with the objective clearance, than it should work fine with a 20 MOA base.

 

[Nelius88]

A 20 MOA base is always nice to have! In that kind of circumstance, It's better to have it and not need it than to need it and not have it I don't believe the ring height will make any difference other than clearance for your scope objective over the base and barrel. If it works on your flat base with the objective clearance, than it should work fine with a 20 MOA base.

Yup, the scope still fits on the rifle with the 00 moa base, just wasn’t sure if I still needed to have the 20 moa base to make the further shots if the scope already sits higher with the taller rings. But yeah, better to have it than not need it. Thanks!

 

[ColinW]

I personally have never had to use larger rings for scope clearance on my 20 MOA bases. If anything, you may need to raise your cheek on the stock for proper eye alignment. Just try it out and see where it's at.

 

[Steel head]

I went through this years ago with my savage.

Started with a 0, quickly hit 1000 and next wanted 1200 then 1500 and had to get a 20 moa.
I have a 45 Moa on the way right now for one of my rifles.

Definitely get the 20 moa.

 

[Nelius88]

I personally have never had to use larger rings for scope clearance on my 20 MOA bases. If anything, you may need to raise your cheek on the stock for proper eye alignment. Just try it out and see where it's at.

Yeah, I originally bought the taller rings before I had this rifle. I’m fine with them as long as it doesn’t have a negative effect other than the eye alignment (which isn’t an issue). Just have to get the upgraded 20 moa rail.

 

[Bradv86]

You didn't mention caliber, however if you are talking PST gen 1 I believe it has ~65MOA travel total in elevation. That gives you 32.5 MOA adjustment up assuming the optic zeros for you at its mechanical center.

If the caliber you are shooting drops less than 32.5 MOA at 1k then you should be able to dial to achieve a hit at 1,000Y.

If it drops more than that, you can dial and hold over the remaining using the reticle, so the technical answer would be that you do not need to replace it, but it is not the optimal solution for shooting that distance.

If you add a 20 MOA base, you would then have approximately 52.5 MOA travel up available in the scope, and would be able to engage much further targets.

The downward angle of the scope is so slight that you would not likely need taller rings unless you are already extremely close to the barrel with your objective lens. I would say go ahead and grab a 20 MOA base and run your same rings.

 

[m1match]

Uhh... you do understand that the height of your rings has nothing to do about whether your scope will have enough elevation adjustment to get to 1000 yards don't you? The cant of your base has everything to do with it though. You didn't say exactly what scope you have or what caliber you're shooting but the Vortex PST Gen 2 5-25 has 20 Mils of total elevation adjustment(remember that's total elevation adjustment up and down, so if you're in the middle, you've got 10 Mils of adjustment up) and if you're shooting 6.5 CM and a 140 grain bullet you'll need about 9 mils of elevation from a 100 yd zero. So if you use your 0 MOA base, you might be able to get to 1000 with your scope. I say might, because if you have to use up a bunch of your up elevation adjustment to get a 100 yd zero, you might not have enough.

 

[Nelius88]

You didn't mention caliber, however if you are talking PST gen 1 I believe it has ~65MOA travel total in elevation. That gives you 32.5 MOA adjustment up assuming the optic zeros for you at its mechanical center.

If the caliber you are shooting drops less than 32.5 MOA at 1k then you should be able to dial to achieve a hit at 1,000Y.

If it drops more than that, you can dial and hold over the remaining using the reticle, so the technical answer would be that you do not need to replace it, but it is not the optimal solution for shooting that distance.

If you add a 20 MOA base, you would then have approximately 52.5 MOA travel up available in the scope, and would be able to engage much further targets.

The downward angle of the scope is so slight that you would not likely need taller rings unless you are already extremely close to the barrel with your objective lens. I would say go ahead and grab a 20 MOA base and run your same rings.

Sorry, it’s a PST gen 2 on a Ruger American Hunter 6.5 Creedmoor. So the taller rings aren’t going to have a negative effect on a 20 moa rail base, got it. Clearance will def not be an issue. Sounds like the 20 moa rail is going to be an appropriate purchase. I found one made by EGW. Thanks for the info.

 

[Nelius88]

Uhh... you do understand that the height of your rings has nothing to do about whether your scope will have enough elevation adjustment to get to 1000 yards don't you? The cant of your base has everything to do with it though. You didn't say exactly what scope you have or what caliber you're shooting but the Vortex PST Gen 2 5-25 has 20 Mils of total elevation adjustment(remember that's total elevation adjustment up and down, so if you're in the middle, you've got 10 Mils of adjustment up) and if you're shooting 6.5 CM and a 140 grain bullet you'll need about 9 mils of elevation from a 100 yd zero. So if you use your 0 MOA base, you might be able to get to 1000 with your scope. I say might, because if you have to use up a bunch of your up elevation adjustment to get a 100 yd zero, you might not have enough.

 

[Nelius88]

Actually I wasn’t sure if it would have any effect, not as in scope clearance but just in correlation with a 20 moa rail and having higher rings. But sounds like it won’t be an issue, thanks for the help.

 

[Bradv86]

Sorry, it’s a PST gen 2 on a Ruger American Hunter 6.5 Creedmoor. So the taller rings aren’t going to have a negative effect on a 20 moa rail base, got it. Clearance will def not be an issue. Sounds like the 20 moa rail is going to be an appropriate purchase. I found one made by EGW. Thanks for the info.

In that case it has a touch more elevation - 70 MOA in the 5-25 and 75 in 3-15. Shooting 6.5 CM vs a .308 for example, you will have less total drop. I would venture to guess you could currently dial to a hit at 1000Y if that is your goal. A 20 MOA base will still do you good, as once you make hits at 1000 you are going to want more.

 

[m1match]

Taller rings only mean that you have to raise your adjustable cheekpiece higher, but that's all. However for you, the Magpul Hunter cheekpiece is adjustable by adding risers, so you might need to buy different risers.

 

[Nelius88]

In that case it has a touch more elevation - 70 MOA in the 5-25 and 75 in 3-15. Shooting 6.5 CM vs a .308 for example, you will have less total drop. I would venture to guess you could currently dial to a hit at 1000Y if that is your goal. A 20 MOA base will still do you good, as once you make hits at 1000 you are going to want more.

Awesome, thanks for the thorough explanation!!!

 

[Nelius88]

Taller rings only mean that you have to raise your adjustable cheekpiece higher, but that's all. However for you, the Magpul Hunter cheekpiece is adjustable by adding risers, so you might need to buy different risers.

Yeah, I’ll have to see how much the sight picture changes once I get the new rail. Thanks for the info!!