Need more elevation in my scope - How do I get it?
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David Hoback
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Just what it says. It’s the TOTAL adjustment range. So, 37.7MOA from bottom of travel to top & left to right. The “1.05”, I’m not sure what they are referring to. It doesn’t make sense. It can’t be the minutes per rotation. And it certainly doesn’t refer to Mils! 37.7 MOA equals 11 Mil.
So I’m not sure on the 1.05 there. However, doesn’t apply to your problem at hand.
Here are the ballistics for your CCI Mini Mag ammunition. And yes, you are about 10MOA shy.
Thanks Dave. I'm a bit confused here. The table seems to say that with a 100 yard zero, the bullet will impact 28.9" low and 13.8 MOA low at 200 yards. How did you get 10 MOA?
And in any case, if the MOA drop is less than 20, does that mean a 20 MOA base or 20 MOA rings will cover me?
And in any case, if the MOA drop is less than 20, does that mean a 20 MOA base or 20 MOA rings will cover me?
Varminterror
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37.70” adjustment at 100 yards = 36moa internal.
That’s equivalent to 1.05m at 100m, so that’s what the 37.7/1.05 means. 37.7” at 100yrds, aka 1.05m at 100m.
Also, it does appear your scope is an IPHY base, not true MOA, with 1/8” per click per hundred yards, so keep that in mind.
So… with that scope and that load - you can’t use any 30 or 40moa base or rings. You can only use up to about 28moa, at very best, so a 25moa Burris insert combo (20+5) would get you almost as much range as possible (around 270 yards), without cutting off your short range, and 20moa base or rings would get you to 200 with no issues.
***Long Version***
That 37.7” at 100yrds is 36moa, meaning optical center is 18moa from either end… stick that on a flat rail on top of a rifle, around 2” optic height (~1moa), and then 200yrds will mean an absolute drop compensation of ~60”, 28.6moa, so you’ll need ~30moa of “up” available just to reach 200yrds… 30moa needed minus 18 available is ~12moa of rail/ring offset needed. Adding a 20moa base would put you ~8moa from the maximum “up” dial available, meaning you’d have 24moa left “down” from 200yrd zero… and you’ll need ~21moa “down” from 200yrd zero to be able to dial for close ranges (peak is ~45yrds)…
If you add a 40moa offset, you will not be able to dial back to short range. 40yrds would need 9.5moa “up” from optical center, but adding 40moa offset puts you at 30.5 “down,” from optical center… but you only have 18 down available… knock down to 30moa angled base or rings, and you’ll still be at 20.5 “down,”with only 18 available… Adding a 20moa base puts you 10.5moa “down” from center, with 18 available, so 20moa works.
With that scope and that load, you could use Burris rings with one 20 and one 5moa insert set, 25moa total, and you’d end up ~3moa from maximum “down” at 40yrds, and have ~34moa available, which would get you to 200, even ~270 yards.
So get a 20moa base or rings - if using Burris rings, use 25moa total insert - and shoot to 200. Do not get a 30 or 40moa offset… at least not for that load and scope combo.
David Hoback
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No, you misunderstood me. I was repeating what you were saying. Based on your shooting. You said with elevation MAXED OUT, you were hitting 10MOA low. Your scope has 37.7moa. If you look at the ballistics chart I posted, it requires approx 46.7moa at 200yds. So your scope is roughly 10MOA short. And that works out fairly true based on what you told us.
David Hoback
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A 20moa rail will give you plenty of adjustment for 200yds. I run a 20moa rail always. And my scope has 36mils of elevation! That’s around 125MOA! But I STILL like having that 20 rail on there.
Varminterror
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This is bad math.
1) The scope in question has 37.7”/100yrds, which is 36moa, not 37.7moa.
2) The available adjustment is a total number, so 36moa is +/-18 from optical center, and without angled mounting options, not all of it can be used. As I described above, the absolute gravitation drop compensation for the Mini-Mag load is 28.5moa at 200yrds, plus 2” (~1moa) of optic height, so he will need ~30moa “up” with that load to reach 200yrds, and only has 18moa available on a flat base… needing at least 12moa angle to get back into his scope… so a 20moa base or rings gets that load back into his scope.
2a) The OP also wants to shoot Wolf Match 40grn RN standard velocity stuff at 1050fps. This load has ~76” of absolute drop to compensate at 200yrds, 36moa, so instead of being 12moa out of his scope, he ends up 18moa out, so a 20moa still works - right on the razor’s edge.
3) Given 20moa to get back into the scope, the Mini-Mag load will peak in its adjustment “down” around 43yrds with a 200yrd zero, about 21moa “down” from 200yrd zero, well within the adjustment capacity of his scope. The Wolf load will hit max adjustment height around 35yrds, with 26.5moa “down” from 200yrd zero… again, well within the adjustment capacity of his scope, as long as he doesn’t use more than ~28moa of angled base or rings…
So 47” from 100yrd zero to reach 100yrds minus 37.7” at 100yrds is just bad math. A completely incorrect interpretation of the mechanical system and associated math.
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JFrank
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Could buy a scope with a smaller objective lens that sat a bit closer to the bore axis.. or order a scope with more internal movement, either way might be an improvement.
David Hoback
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Varminterror
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You can say it, but it doesn’t make it true.
His scope has 37.7” per hundred yards TOTAL adjustment. He won’t have access to all of it - such subtracting the way you did could work - unless he has an angled base. 46.7 - 37.7 ain’t how it works, because he only has access to half of it without an angled base. So yes, YOUR math presented above was wrong.
Does your scope have a “30-30” reticle, with the thicker crosshairs at the outer end and a thinner crosshair in the center? When I first started shooting my Marlin 60 I zeroed on the thick/thin transition at 175 yards just to see what would happen. It’s not ideal but it’s free.
The scope rings that came with my first scope wouldn’t clamp tight enough. I replaced them with a 1 piece ring/base that clamps directly to the 3/8” dovetail on the receiver and haven’t had any more trouble. It has three screws holding it to the dovetail. I think someone sent me a link way back that had a similar one piece base/rings but it had 5 screws to clamp it to the dovetail and 20 MOA built into it. I don’t remember who made/makes it though.
All that said, now I want to take my Marlin past 175 to 200. That’s the max at my local range.
The scope rings that came with my first scope wouldn’t clamp tight enough. I replaced them with a 1 piece ring/base that clamps directly to the 3/8” dovetail on the receiver and haven’t had any more trouble. It has three screws holding it to the dovetail. I think someone sent me a link way back that had a similar one piece base/rings but it had 5 screws to clamp it to the dovetail and 20 MOA built into it. I don’t remember who made/makes it though.
All that said, now I want to take my Marlin past 175 to 200. That’s the max at my local range.
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