Question about scope ring/mount height between comp & trainer

[EchoDeltaSierra]

I'm building a V-22 trainer. It will be in the same chassis as my centerfire competition rifle. I am using a 56mm bell Nightforce ATACR-R in a ARC 35mm high one-piece mount on the center fire. I have a 50mm bell SVH F1 for the V-22 and 32mm ARC rings would probably allow the SHV to clear the nightvision bridge on the chassis.

Should I go with the 32mm rings, or should I keep the bore over identical and go with another 35mm high one piece mount so I'm running identical bore over measurements between the two guns? Just curious other's thoughts.

 

[antithesis]

Different tubes. You are still going to come up 2mm short with the 35. Guessing you could adjust your comb to not notice 2mm, but I think 5mm would change the feel.

None of the above means much if your actions are not the same height.

 

[EchoDeltaSierra]

Different tubes. You are still going to come up 2mm short with the 35. Guessing you could adjust your comb to not notice 2mm, but I think 5mm would change the feel.

None of the above means much if your actions are not the same height.

The ARC measurements are at the center of the mount, thus if one has a 30mm or 34mm tube, their 35mm one-pice puts the reticle center at that height... thus the same bore over.

That said, now that I think about it a bit more, I'll be running a 30 moa base on my trainer and a 20 moa on my centerfire, so there is some variance. I might just save the money and do the rings.

 

[antithesis]

Makes sense. I was not thinking about it that way.

I think the biggest thing is the chassis. I can switch between different systems that have the same chassis and things are pretty automatic. Going between different chassis takes a minute to get comfortable.

 

[goosed]

The ARC measurements are at the center of the mount, thus if one has a 30mm or 34mm tube, their 35mm one-pice puts the reticle center at that height... thus the same bore over.

That said, now that I think about it a bit more, I'll be running a 30 moa base on my trainer and a 20 moa on my centerfire, so there is some variance. I might just save the money and do the rings.

Not sure I understand your goal and even more confused why 20MOA vs 30 MOA makes any difference?

Is your goal to achieve scaled ballistic drops between the 22 trainer and center fire match gun at specific ranges?

 

[EchoDeltaSierra]

Not sure I understand your goal and even more confused why 20MOA vs 30 MOA makes any difference?

Is your goal to achieve scaled ballistic drops between the 22 trainer and center fire match gun at specific ranges?

The actual variance is that the bore over would be different slightly a the point of measurement (usually the barrel side of the action)... Thus, if I'm trying to get a bore-over accurate to 1/100th (which I have for my center fire), and I got the same mount (35mm), I would still have a difference to factor due to other mechanical differences.

The reason for 20moa on my 6.5CR and 30moa on my 22LR is that I need (want) more adjustment for the sake of stretching that little bullet to it's extent. 200y = 8.0mils; 300 = 15.2 mils. I regularly shoot to 220y and any extra elevation would be used on this rifle. I currently have 20moa on my 10/22 rail and usually seem to want more elevation, so I'm doing 30moa on the V-22.

 

[goosed]

The actual variance is that the bore over would be different slightly a the point of measurement (usually the barrel side of the action)... Thus, if I'm trying to get a bore-over accurate to 1/100th (which I have for my center fire), and I got the same mount (35mm), I would still have a difference to factor due to other mechanical differences.

The reason for 20moa on my 6.5CR and 30moa on my 22LR is that I need (want) more adjustment for the sake of stretching that little bullet to it's extent. 200y = 8.0mils; 300 = 15.2 mils. I regularly shoot to 220y and any extra elevation would be used on this rifle. I currently have 20moa on my 10/22 rail and usually seem to want more elevation, so I'm doing 30moa on the V-22.

Understood.

I still don't understand why matching bore over height is so important?

 

[EchoDeltaSierra]

I still don't understand why matching bore over height is so important?

Neither do I, which is why I'm asking dumb questions in front of a large audience.

 

[PoniesWhee]

I wouldn't think your bore over height is an issue as long as you have the same cheek weld between the two guns