Rifle Scopes Stupid questions no Search can answer (yet)

[JeffMichaud]

Please note this is my 2nd post, but not my 2nd visit. I've been reading and searching about tactical scopes for months with peaked curiosity and wonderment. I actually have a Savage 10HP that I have yet to fire as I can't settle on a scope, but hopefully the experts here can help me "pull the trigger".

1) Where does the difference between .25"MOA and .5"MOA come into play. I was told by someone that I wouldn't need to make such fine adjustments until I was shooting beyond 800 yards (btw he was selling a .5"MOA scope. Follow up question: am I better off with a scope using Mil turrets anyways and this first question is irrelevant?

2)I wish I could find the article to quote, but I was reading that one issue with a large 50mm bell is the high rings required will cause the operator to never have a good cheek weld without installing a riser, and that in the end the larger bell is just a fad. The writers opinion was that the eye can only intake so much light, and that a 40mm objective provides more than the eye can intake, so the 50mm's were unnecessary overkill. And combined with the issue of getting a good cheek weld made 50mm scopes a poor choice.

3)Is the 20MOA canted base on my rifle going to have to be replaced if I go with a 40mm scope? Isn't it for 50mm bells, or better question might be, what's a canted base's purpose?

4) What's the best scope? Kidding. I'm thinking I should start with a 3-10x40mm scope for starters in Mil/Mil so I can learn the basics of shooting short range for hunting and longer for fun. I think I want a scope with more versatility than a fixed provides, but functional at both 100-200 yards and also 500-750 yards with my .308. I get the impression scopes with higher magnification like 6-20 make shooting at shorter ranges an issue and that having such a long range of magnification is more choice than the real world ever make necessary. Also I was under the impression that above 10x or 12x power the mirage and parallax issues are really problematic and one should learn to rely on 10x as a max. Am I thinking correctly about this stuff?

 

[Spuhr]

Re: Stupid questions no Search can answer (yet)

Hi

If you are going to buy a mil/mil scope there is no such diskucison such as .25MOA or .5 Moa
As the click on such a scope is closer to .35 MOA and you are better of dropping MOA for the future.

I can't see a reason to have finer adjustments than 0,1 MRad for a long range scope, that just makes calculations difficult and errors more frequent.

I think your butplate and cheekpiece should be placed where it needs for your best shooting, and not where the manufacturer have placed it. So the objetive bell doesent matter, as the gun needs a adjustable buttplate and cheekpiece anyway.....

The point with the tilted base it to give you the adjustment on the right side. Makeing it possible to adjust out the scope to 800 meters for example. With a nontilted mount you are maybe able to adjust the scope out to 450 meters as you will then have a big portion of the adjustments where you don't need it.

Håkan

 

[Jakerz]

Re: Stupid questions no Search can answer (yet)

Spuhr hit most of the stuff, I would say go with Mil/Mil so you can use the standard Mildot reticle without having a lot of math involved.

the 50mm is pretty standard, and dont let someone tell you it has to be mounted high, there full of shit, lol. That being said I love my SN-3 with the 44mm objective.

How much are you willing to spend?

 

[McCrazy]

Re: Stupid questions no Search can answer (yet)

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: GeneralDisarray</div><div class="ubbcode-body">
1) Where does the difference between .25"MOA and .5"MOA come into play. I was told by someone that I wouldn't need to make such fine adjustments until I was shooting beyond 800 yards (btw he was selling a .5"MOA scope. Follow up question: am I better off with a scope using Mil turrets anyways and this first question is irrelevant?

Mil adjustments have their advocates and I like them as well, but MOAs get the job done too. Contrary to what the guy told you, .25moa adjustments will be very frustrating if you transition much from 1,000 yards to 100 and anywhere in between much. I have another scope that has 1moa adjustments for elevation and .5moa windage which I find to be too coarse. I think .5moa would be about right for elevation and .25moa for windage.

2)I wish I could find the article to quote, but I was reading that one issue with a large 50mm bell is the high rings required will cause the operator to never have a good cheek weld without installing a riser, and that in the end the larger bell is just a fad. The writers opinion was that the eye can only intake so much light, and that a 40mm objective provides more than the eye can intake, so the 50mm's were unnecessary overkill. And combined with the issue of getting a good cheek weld made 50mm scopes a poor choice.

Larger diameter objectives lenses do present several problems without offering much for advantages. 50mm is not huge, but I don't see much reason to go significantly larger.

3)Is the 20MOA canted base on my rifle going to have to be replaced if I go with a 40mm scope? Isn't it for 50mm bells, or better question might be, what's a canted base's purpose?

A 20moa base doesn't care if it is supporting a 20mm objective lens or a 80mm lens. It just provides additional slope so the scope can use less of it's internal adjustments to get to the same distance as a similar set-up with a flat base.

4) What's the best scope? Kidding. I'm thinking I should start with a 3-10x40mm scope for starters in Mil/Mil so I can learn the basics of shooting short range for hunting and longer for fun. I think I want a scope with more versatility than a fixed provides, but functional at both 100-200 yards and also 500-750 yards with my .308. I get the impression scopes with higher magnification like 6-20 make shooting at shorter ranges an issue and that having such a long range of magnification is more choice than the real world ever make necessary. Also I was under the impression that above 10x or 12x power the mirage and parallax issues are really problematic and one should learn to rely on 10x as a max. Am I thinking correctly about this stuff?

One of my scopes is a 10x fixed. It is too low a power to be very precise at 100 yards as well as 1,000 yards but it gets the job done. If you were to get a 3-10x variable, I doubt you would ever take it off 10x. the 6x-20x would be a good bet. I have a 3.2-17x and it works much more satisfactorily for my purposes than the fixed 10x.
</div></div>

 

[JeffMichaud]

Re: Stupid questions no Search can answer (yet)

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Spuhr</div><div class="ubbcode-body">So the objetive bell doesent matter, as the gun needs a adjustable buttplate and cheekpiece anyway.....</div></div>

I don't have one of those types of stocks. What then? Shouldn't I have a smaller objective on the scope (40mm?) with low-med rings so my chin isn't on the stock instead of my cheek?

 

[Spuhr]

Re: Stupid questions no Search can answer (yet)

McCrazy

The discussion about how much light the human eye can use supports the use of VERY large objetives.
The Human eye is said in mostly cases to be maximum 7mm.
With age this dimension goes down and in many cases it's around 6mm at the age of 40.
A 10x40 scope have an exit pupil of 4mm, that is lot less than the human eye can use and ut requires that the eye is perfectly behind to not loose a lot of light.
The exit pupil on a 3-12x56 set at 12X is 4,6mm, still a lot less than the human eye can use.
On a 6-24x72 the exit pupil is 6mm at 12X and 3mm at 24X.
So the more power you have the more objective you need.
That is if you are shooting in low light, if you only shoot in sunny days you can have whatever objetive you like.

General disarray
I would recoment you to have an adjustable butplate fitted to your gun. A straight stock is simply to low to get a low shooting position and the but plate needs to be higher.

BUT If you have a look, you will maybe see that there is no different in height on the mounts betwen a 40 or a 50mm lens.
This is all depending on your gun and you rail, how high they are.

Håkan

 

[McCrazy]

Re: Stupid questions no Search can answer (yet)

You can rig something up on the cheap to help with comb-height to assist having a cheek rest. A new $800 stock is not the only fix. Plenty of stock packs and cheek-rests out there to choose from.

Spuhr- while the human eye may be able to USE more light it does not NEED more light. Smaller scopes get the job done every day. I'm not an optics expert but a scope with a large enough diameter objective lens to result in a 7mm exit pupil would have other short-comings making it impractical for many uses.

 

[Spuhr]

Re: Stupid questions no Search can answer (yet)

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: McCrazy</div><div class="ubbcode-body">
Spuhr- while the human eye may be able to USE more light it does not NEED more light. Smaller scopes get the job done every day. I'm not an optics expert but a scope with a large enough diameter objective lens to result in a 7mm exit pupil would have other short-comings making it impractical for many uses. </div></div>

Yes that is what I tried to say.
If you are satisfied with system for sunny days you for a small objective, and if you need something for more shooting hours you go for bigger lenses.
Remenber, you can only hit what you can see.
If you can't see it, you can't hit it.

A 50 lens can't be unpractical on a sniperrifle, where the main bulk and weight comes from the gun.....
On a light hunting rifle the situatin is somewhat different but not on a sniping gun.

Håkan

 

[exhogflyer]

Re: Stupid questions no Search can answer (yet)

1) .25 or .50 moa can come into play at any range, it depends on what you are shooting.Remember that's 1/4" or 1/2" at 100 yds, but at 400 yds it's now 1" or 2".Depends on how small a target you are shooting or how accurate you want to be.
2) while it's true that the eye can only admit so much light( the size of the exit pupil of the scope determines this)remember that as you go up in magnification the EP gets smaller.Also dusk/dawn/cloudy shooting you have less light,which is why many scopes do have 44-50mm obj.They can be easily mounted without being too tall.
3) a canted base is generally used for longer range shooting, it allows you to keep the scopes adjustment range "centered" for mid ranges while still allowing enuff "up" to get you to, say, 1000 yds.When a scope is cranked to the limits, windage for example may be limited.Remember it's a tube, so there's less movement near the top or bottom.Also the optics will be clearer away from the edges (generally)
4)scope selection is another matter that could cover volumes, biggest key is you get what you pay for and you need to narrow it down with some type of budget.Yes, mirage is more of an issue at higher mags( when hot/sunny)and parallax CAN be if not adjusted correctly.Also, what will you be shooting at...varmints? Paper targets? Large critters? It makes a difference...

 

[jrob300]

Re: Stupid questions no Search can answer (yet)

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: GeneralDisarray</div><div class="ubbcode-body">
I don't have one of those types of stocks. What then? </div></div>

You can use a stock pack and put a strip from a mouse pad (or 2) under it to get proper weld. If that is not enough, you can buy a Karsten Kydex adjustable cheek rest.

John