Reticle Canted Despite Level Scope Body

[bnewt3]

All of this is why this device is a fool proof, no brainer way to mount a scope.

Parabola LLC

parabola-llc.com

But if the reticle and/or erector are off......that device doesnt fix anything. It gets the reticle straight, but then elevation becomes windage and windage becomes elevation.

 

[Formidilosus]

Form, thanks for your reply. Understood. Do you recommend a more accurate level for scope mounting? Or should I just align the reticle to the plumb line and call it a day? Perhaps the reticle is not canted at all and the level is to blame?

Level the reticle to the rifle. Go shoot and stop fretting.

 

[Formidilosus]

But if the reticle and/or erector are off......that device doesnt fix anything. It gets the reticle straight, but then elevation becomes windage and windage becomes elevation.

Let’s assume that the reticle is canted from the erector- it almost certainly isn’t. But, let’s say it is by the amount shown above- how much do you think it will effect a shot at say 1,000 yards with standard cartridges?

 

[BLJ]

6.7”.

 

[Formidilosus]

6.7”.

How much do you believe the cant is as shown?

 

[BLJ]

No idea. I was just guessing a measurement.

 

[Q_Sertorius]

I think the picture on the wall being crooked is throwing you off.

Honestly, not much there looks straight to me. And trying to determine level off one of those silly little bubble levels is very frustrating. They aren’t very accurate. I’ve spent a lot of time carefully aligning the level-level tools, only to raise the rifle and observe a noticeable angle. Having a picatinny-mounted level on the action (like the UM one) is nice. Although with its short scale, it’s probably not much more accurate. But most of the time I just raise the rifle and make sure it looks right.

I hunted for years with a scope that was slightly canted. It never made any issues apart from bothering me immensely. I was just using Kentucky windage and holdovers, so the thing could have been off by 45* and it still would have worked.

 

[JGRaider]

But if the reticle and/or erector are off......that device doesnt fix anything. It gets the reticle straight, but then elevation becomes windage and windage becomes elevation.

It gets the reticle in perfect alignment with the rifle bore, which is where the rubber meets the road.

 

[bnewt3]

Let’s assume that the reticle is canted from the erector- it almost certainly isn’t. But, let’s say it is by the amount shown above- how much do you think it will effect a shot at say 1,000 yards with standard cartridges?

3-4 inches.


Thats 3-4 inches in addition to whichever way I find to screw up a shot. I promise I dont need any help making a bad shot. I can do it all by myself.

 

[bnewt3]

It gets the reticle in perfect alignment with the rifle bore, which is where the rubber meets the road.

Maybe it does.

maybe the holes in the receiver arent perfectly at 0 degrees on the receiver, maybe the axis of the holes and the bore arent the same, maybe the rings have have some variance that stacks with the first 2. Maybe the variance in the rings erases one of the first 2 possibilities.

I really wish we could trust that everything was made properly but we cant Which is why scope mounting, no matter the method, needs to be checked with a tall target test if shooting past roughly MPBR.

 

[Marbles]

Make the reticle true to the plumb line. Put a scope level on it that is true to the reticle. You can do this by either adjusting the scope in the rings or by just canting the whole assembly until the reticle is plumb and setting the level.

Go shoot a tall target test at 100 yards to make sure adjusting elevation doesn't shift POI left or right (using scope level for every shot and two 10 round groups or until you are confident).

If POI meaningfully shifts left or right, then send it back.

It really doesn't matter if the scope and rifle are plumb to each other, so long as the reticle is true and the scope tracks correctly.

 

[Formidilosus]

3-4 inches.

Not even close.

You all are pole vaulting over mouse turds.

 

[HuntHarder]

That level is adjustable isn't it? I think there are tiny set screws to adjust it and true it. Have you trued it to another level you trust?

 

[Kyguy]

Not even close.

You all are pole vaulting over mouse turds.

This will be the best reply I read on a forum for quite some time!

 

[nm.otter]

Assuming my UM Tikka rail level is 3° off my bore/action axis, the reticle center would have a 0.087" horizontal offset from that axis -- less than the diameter of a typical mouse turd.

 

[Marbles]

So, measuring, you are off by less than 1 degree (about 0.7 degrees). That is too little to matter. For every 80 mils dialed of elevation, you would be about 1 mil off on windage (assuming it tracks with the cant).

Dial up 10 mils and you will have a 0.125 mil shift in windage (between 1/4 to 1/2 MOA). My 223 is 11.3 mils of elevation for 1000 yards at sea level, so about 4.5 inches of windage (close to worst case on a centerfire). Would only really start to show on a rimfire for most uses.