Question Regarding Scope Elevation Adjustment on a Ruger No. 1 45-70

[Dobeman887]

For starters, it took me quite some time to simply get my current 1" Leupold VX3 with a 50mm objective to fit on my Ruger #1 with an EGW picatinny rail on top. I used Warne high rings and the bell of the objective just barely clears the picatinny rail. I have it zeroed using 300gr Barnes 300grn TSX FB bullets, using IMR 4198 (can't remember the charge off the top of my head), but about 2100fps at the muzzle. I was excited to try out Bear Creek Ballistics 250gr HV bullets with a charge of 55.5grns of Accurate 1680. They grouped incredibly well, at about 2600fps. The problem is that I have run out of elevation adjustment with this bullet. I can't get them any lower than about 10 inches from the top of the bullseye. I could leave everything as is, and just shoot the rifle with my current set up/bullet combination, but would really like to do something to allow me to use the 250gr Beer Creek bullet. As I see it, it might be possible to go to a 30mm tube, but I don't think that would even allow me to get enough adjustment. If my math is right I would need approximately 40 more clicks of adjustment to bring that bullet down enough to zero it at 100yrds?? I could take off the picatinny rail and use Ruger rings but then the bell of a 50mm scope would hit the barrel. Any ideas??

 

[WeiserBucks]

Zero stop?

 

[Johnwell]

I think burris signature rings might be your best option if you’re set on using this scope. I think you can get 20moa of “misalignment” in the rings to help center the reticle.

 

[Dobeman887]

Zero stop?

This model Leupold does not have the zero stop- the turrets are capped

 

[Dobeman887]

I think burris signature rings might be your best option if you’re set on using this scope. I think you can get 20moa of “misalignment” in the rings to help center the reticle.

But I "think" those rings take the alignment up in elevation instead of what I need (I need to bring my zero down for the bullet I would prefer to use).

 

[Dobeman887]

I think burris signature rings might be your best option if you’re set on using this scope. I think you can get 20moa of “misalignment” in the rings to help center the reticle.

I just looked at them more carefully and see how they work now. I "might" be able to decrease my elevation enough with those rings, but I wonder if the bell of the objective lens would then hit the picatinny rail??? I will measure the gap, and take a picture and post it.

 

[Johnwell]

I just looked at them more carefully and see how they work now. I "might" be able to decrease my elevation enough with those rings, but I wonder if the bell of the objective lens would then hit the picatinny rail??? I will measure the gap, and take a picture and post it.

It might hit depending on clearance—as you add inclination to your scope it will definitely be pointed towards the barrel, although 20moa is only .333 degrees, so it may not be an issue.

 

[TaperPin]

I wonder what’s got the scope and bore centerlines so far off? These scopes only have +/- 25ish MOA movement from center, so you’re close to 35 MOA from center. If the outermost Ruger base screws are 5” apart and there’s 3,600 inches in 100 yards, that’s .72” in movement on target for every .001” of base misalignment. 35ish MOA divided by .72” is .049”ish of base misalignment, or about the thickness of a dime. Hmm….

Is the scope or barrel bent, or the base milled wonky?

Not that it helps, but fixed Leupold scopes have roughly +/- 40 MOA of adjustment range. Most 30mm scopes have more than that.

I like the idea of Burris Signature rings.

 

[Johnwell]

I just looked at them more carefully and see how they work now. I "might" be able to decrease my elevation enough with those rings, but I wonder if the bell of the objective lens would then hit the picatinny rail??? I will measure the gap, and take a picture and post it.

I was thinking about this, and you shouldn’t have any issues with scope clearance, assuming the rings are the same height. To get the bullet impact to go down, you’ll be tipping the scope objective up so you should have improved clearance.

 

[pacoalcracker]

I believe a 30mm tube scope with a 42mm objective will give you much better light transmission than a 1" tube and 50mm objective. I would go that route and solve the entire issue. In addition, it's a stronger, more durable scope and would even have better aesthetics.

 

[Johnwell]

I believe a 30mm tube scope with a 42mm objective will give you much better light transmission than a 1" tube and 50mm objective. I would go that route and solve the entire issue. In addition, it's a stronger, more durable scope and would even have better aesthetics.

Light transmission doesn’t have anything to do with tube size. But it would generally have more internal adjustment so the OP might be able to zero it.

 

[Dobeman887]

Thanks for the various ideas everyone- the problem rests with the picatinny rail I think. I had to purchase three different sets of rings before I could find ones that would allow me to mount the scope and zero some rounds at 100yrds. The problem centered around the inability to use Ruger rings with a 50mm objective scope, so I added the picatinny rail in order to accept the scope. I had spent $1700 on the rifle, and had the scope from my Henry 45-70 I sold, so I didn't want to purchase another scope. Our gun season begins here in IL in a week and a half, which isn't going to give me enough time to play around with this between work and bow hunting the rut. There is certainly nothing "wrong" with the 300gr Barnes copper I am using, but it would be nice to gain an extra 500-600fps from the Beer Creek bullets I loaded. I will probably purchase a set of Burris rings and give that a shot between firearm seasons. And it certainly isn't as if the Ruger is my only option, my primary firearm for deer hunting is my custom smokeless .45 muzzleloader (my favorite deer hunting firearm for longer ranges). As most of you probably know, in IL we are limited to shot guns, muzzleloaders, and single-feed straight wall cartridges.

 

[Dobeman887]

I was thinking about this, and you shouldn’t have any issues with scope clearance, assuming the rings are the same height. To get the bullet impact to go down, you’ll be tipping the scope objective up so you should have improved clearance.

As the objective end of the scope goes up, so will the bullet impact.

 

[Johnwell]

As the objective end of the scope goes up, so will the bullet impact.

So right now, the scope is looking down below the bullet impact.

You could think of it like two crossing lines. The scope is looking at the target, the bullet is above the target; therefore if the barrel was level the scope is pointing down towards the bore. To make the bullet impact go down, the objective bell of the scope needs to go up to make the two lines closer to parallel. You essentially need the opposite of a 20moa base.

 

[Caseknife]

As the objective end of the scope goes up, so will the bullet impact.

Totally opposite

 

[Dobeman887]

So right now, the scope is looking down below the bullet impact.

You could think of it like two crossing lines. The scope is looking at the target, the bullet is above the target; therefore if the barrel was level the scope is pointing down towards the bore. To make the bullet impact go down, the objective bell of the scope needs to go up to make the two lines closer to parallel. You essentially need the opposite of a 20moa base.

I'll take your word for it, my spatially-limited mind can't figure it out, but if you say raising the objective works then I'll go with that. So, if my bullet impact is 10 inches above the bullseye will the Burris rings be able to correct it enough to be able to zero at 100yrds? I am at work and the Burris website is blocked, but it "appears" I can gain that much elevation adjustment based on the youtube video I have watched. My other question is "why height Burris XTR signature rings would I need to get"? I am using extra high Warne rings right now, but without having them both in front of me it is difficult to compare apples to apples. After doing a google search it appears the "height" of the Warne extra high rings is .850 inches, but is that measured from the base of the rings to the center of the tube?? On the other hand, the Burris signature 1" rings state the low rings are 1 inch measured from base to the center of the tube. I am thinking I would go with the lowest model Burris Signature rings to match up with my Extra High Warne rings? Once again, thanks to all helping me figure this out.