Rifle Scopes Choosing your Zero (effect on total elevation)...

[Victor Co Heather]

This is making my head hurt.

Does changing your zero (100 yard, 200 yard, 300 yard) give you extra elevation in the total available elevation from any given scope? (without changing your base)

For example:

If you dial a 100 yard zero and then you check your total elevation travel, let's say you get 20 mils of up elevation.

Then you rezero the same scope at 300 yards, you first will have to move your zero up 1 full mill to get your zero and slip the turrets to read "0". Now that's it's zeroed at 300 you only have 19 full mils of elevation left in the scope.

Right?

or no?

 

[TiroFijo]

Re: Choosing your Zero (affect on total elevation)...

right

 

[Target In Sight]

Re: Choosing your Zero (affect on total elevation)...

Don't mean to hi-jack the thread, but this got me thinking.

What if you have a USO with the EREK knob, zeroed at 300yd, then bottom out the clicks, does it give you more elevation then?

Sorry if its a dumb question...

 

[Dogtown]

Re: Choosing your Zero (affect on total elevation)...

Now, how does that change with a 40MOA base?

 

[VKC]

Re: Choosing your Zero (affect on total elevation)...

Rezeroing with just dialing your scope or adjusting your zerostop, won't give you more overall elevation. However, going from a flat scope base to 20MOA, or 20MOA to 30 or 40MOA, and then rezeroing, will give you more elevation.

 

[Rob01]

Re: Choosing your Zero (affect on total elevation)...

Stick with a 100 yard zero. From there everything is dialing up whether you are going further or closer. Less chance to get lost on the knob.

 

[Victor Co Heather]

Re: Choosing your Zero (affect on total elevation)...

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: vkc</div><div class="ubbcode-body">Rezeroing with just dialing your scope or adjusting your zerostop, won't give you more overall elevation. However, going from a flat scope base to 20MOA, or 20MOA to 30 or 40MOA, and then rezeroing, will give you more elevation. </div></div>

Ahh yes, this is what I was thinking.

Ok so your zero is arbitrary to overall elevation... it's the overall total MOA base cant and the scope's turret travel that determine max elevation.

 

[Victor Co Heather]

Re: Choosing your Zero (affect on total elevation)...

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Dogtown</div><div class="ubbcode-body">Now, how does that change with a 40MOA base? </div></div>

That would be changing the equation to give 40 moa of travel.

My question is regarding the isolation of all other factors, does the zero distance add or subtract from the overall elevation of any given setup.

 

[maladat]

Re: Choosing your Zero (affect on total elevation)...

I read a compelling argument made here on the hide for using a 100 yard zero.

If you zero significantly farther out than 100 yards, atmospheric conditions start to have a noticeable affect on your zero so you have to adjust zero for conditions then start adjusting for range.

I.E., you zero at sea level at 300 yards. Now you take your rifle up to 5000 feet for a competition in Denver. You print out new dope cards that all say 300 yards - 0. But because the air is thinner, you're not hitting zero at 300 yards anymore, you're hitting high, so your dope cards don't work until you rezero, then start adjusting for range.

Apparently with a 100 yard zero this effect is pretty negligible.

 

[Pat M]

Re: Choosing your Zero (affect on total elevation)...

I try and go with a 100yd zero on all my rifle (22lr,308,260,300wm) because i don't want to forget and miss dial when shooting different rifles (Keeping It Simple)

 

[Victor Co Heather]

Re: Choosing your Zero (affect on total elevation)...

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: maladat</div><div class="ubbcode-body">I read a compelling argument made here on the hide for using a 100 yard zero.

If you zero significantly farther out than 100 yards, atmospheric conditions start to have a noticeable affect on your zero so you have to adjust zero for conditions then start adjusting for range.

I.E., you zero at sea level at 300 yards. Now you take your rifle up to 5000 feet for a competition in Denver. You print out new dope cards that all say 300 yards - 0. But because the air is thinner, you're not hitting zero at 300 yards anymore, you're hitting high, so your dope cards don't work until you rezero, then start adjusting for range.

Apparently with a 100 yard zero this effect is pretty negligible. </div></div>

I think a 100 yard zero makes sense for me, though some hunters and military professionals might use a 200-300 yard zero due to the nature of the job. (eg not having to dial elevation in a quick shoot environment)

 

[maladat]

Re: Choosing your Zero (affect on total elevation)...

Oh, don't get me wrong, my old deer rifle with a duplex reticle and adjustment knobs you have to turn with a coin is zeroed at 200. I'm not going to take a shot at more than 250-300 yards and within that range it's always "close enough." I wouldn't do it on a long range rifle, though.

 

[J.Boyette]

Re: Choosing your Zero (affect on total elevation)...

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: maladat</div><div class="ubbcode-body">I read a compelling argument made here on the hide for using a 100 yard zero.

If you zero significantly farther out than 100 yards, atmospheric conditions start to have a noticeable affect on your zero so you have to adjust zero for conditions then start adjusting for range.

I.E., you zero at sea level at 300 yards. Now you take your rifle up to 5000 feet for a competition in Denver. You print out new dope cards that all say 300 yards - 0. But because the air is thinner, you're not hitting zero at 300 yards anymore, you're hitting high, so your dope cards don't work until you rezero, then start adjusting for range.

Apparently with a 100 yard zero this effect is pretty negligible. </div></div>

not true.

The shift, is the saem no matter how far you or close you shoot. If the changes in the location moves you .5 MOA, will its .5 MOA at all ranges.

I run a 100yd ZERO because I can. No more thought to it past that.

IF I want to run a MOA knobed scope, and I have limited elevation to dial I have been known to run a 600yd ZERO and hold 0-600yds and dial 600 yds +

So its up to you and the rifle.

I have friends that shoot 1000yd F-class and run a 1000yd ZERO because that what the rifle setup is for.

1000yd shooting

John

 

[ewoaf]

Re: Choosing your Zero (affect on total elevation)...

i have a 200 yd zero because that is exactly where my zero stop stops....easy decision.

 

[maladat]

Re: Choosing your Zero (affect on total elevation)...

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: J.Boyette</div><div class="ubbcode-body">
The shift, is the saem no matter how far you or close you shoot. If the changes in the location moves you .5 MOA, will its .5 MOA at all ranges.</div></div>

I agree that if your zero point moves .5 MOA, you will be .5 MOA off your dope cards at all ranges, but it's still something you have to correct for with changes in atmospheric conditions and a long range zero. With a 100 yard zero, your zero point moves by a smaller angular amount than with a longer range zero so you have less error and don't have to worry about dialing that initial correction to use your range cards that say 100 yards - 0.

The error gets worse at longer ranges because the relative velocity difference between two projectiles in different conditions increases as flight time increases.

I ran some numbers in JBM and it looks like the difference is pretty small until you get out to at least a 300+ yard zero and at 300 yards only for big changes in altitude.

 

[Victor Co Heather]

Re: Choosing your Zero (affect on total elevation)...

I do think it's smart to run a 100 yard zero on my .338LM for my purposes, easy to set up the target, not a lot of atmospheric influence, and it's a uniform zero with all my other sticks.

I think my original question is cleared up: Which was, whatever zero I choose has no effect on total movement in elevation of my scope and base, it's simply arbitrary. Choosing a 300 yard zero is not going to give me more max elevation than a 100 yard zero with the same scope base.