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Weapons and Gear => Gear and Accessories => Topic started by: FMJ on March 06, 2009, 06:49:38 pm

Title: Scope School
Post by: FMJ on March 06, 2009, 06:49:38 pm
I am a young man who still has a lot to learn about firearms and you may have noticed that I ask a lot of questions periodically.  I think that WTA is a great educational resource when it comes to the shooting sports and firearms technology.

Here is a new set of questions I have about scopes and how they work:

I know that a lot of the big scope brands today include Swarovski, Zeiss, Leupold, Trijicon, Bushnell, etc. but I want to understand how exactly they work.

What is parallax? And what does the parallax knob on the scope do?

What is windage? And what does its knob do?

What does magnification mean (as in a 4x for example)  Would a scope with a larger number have more or less magnification?

Is it true that modern scopes are filled with special gasses to prevent fogging?

How are scope bases tapped and drilled to be mounted on receivers?

Are there scopes designed to operate specifically in low-light areas or vice-versa?

And finally, where can I learn more about MOA and milradians?

Thank you for your time.
Title: Re: Scope School
Post by: Thernlund on March 06, 2009, 07:02:13 pm
Parallax is how you gauge depth.  Your eyes see an object from two different angles.  Your brain uses the difference, or parallax, to gauge depth. 

The lack of parallax is how cinematographers achieve "forced perspective".  That is, placing one object further away than another in order to make one appear smaller that the other.  This technique was used to great effect in Lord of the Rings.  If however the camera had moved in the scenes where forced perspective had been used, the effect would have been blown as you would have seen the two objects move differently in relation to each other as the perspective changed.

Move from side to side and you'll notice that closer objects appear to move faster that further away objects.  This example of camera parallax from Wiki...

(http://upload.wikimedia.org/wikipedia/commons/a/ab/Parallax.gif)

For a scope, the parallax knob is what you adjust to keep the reticle on your target as you move your head from side to side.  That is, if you move your head in relation to the scope, the crosshairs stay on the target.

Wiki can explain parallax in this article...

http://en.wikipedia.org/wiki/Telescopic_sight (http://en.wikipedia.org/wiki/Telescopic_sight)

Windage is the side to side movement of the reticle in a scope.  Wind, moving from one side to the other, can be compensated for in this manner.

Larger number means higher magnification.  Sometimes you may see two numbers.  4-16x30mm for example.  the "4-16" means it's variable power with a range from 4 times magnification to 16 times.  The "30mm" refers to the size of the lens in the objective bell (the end opposite the one you look through).

Modern scopes are usually nitrogen-filled.

Mounting is something someone else will have to answer.  I've never mounted a scope.

There are night-vision scopes.  As well, some scopes have lighted reticles for use in low light.

You can learn about MOA easily enough from Wiki.

http://en.wikipedia.org/wiki/Minute_of_arc (http://en.wikipedia.org/wiki/Minute_of_arc)


-T.
Title: Re: Scope School
Post by: Outbreak on March 06, 2009, 07:39:34 pm
MOA is "Minute of Angle," or 1/60 of a degree. 60 minutes equal 1 degree.
http://en.wikipedia.org/wiki/1_in_60_rule (http://en.wikipedia.org/wiki/1_in_60_rule)

We use a similar, if less precise, formula in navigation. We call it the "60 to 1 rule" For every 60 units of distance (range), one degree difference in direction will move the end point one unit. So as shooting goes, if you fired a bullet from 60ft, and your scope was off by one degree, your bullet would hit one foot from the bullseye. Since that's quite inaccurate when it comes to shooting, they measure it in Minutes of Angle, which is 60 times more precise. Now instead of being off by 1 foot at a range of 60 feet, you're only off by 0.2in.

The wiki article above says its only for air navigation, but its applicable to so many other things. At 60mph, you travel one mile in one minute. And it's completely scalable. 120mph is 2 miles per minute, and so on. One degree off for 120 feet will put you 2 feet off. 2 degrees over 60 feet also put you 2 feet off. etc. I'll stop. I could seriously talk about the uses of the 60 to 1 rule all day.
Title: Re: Scope School
Post by: FMJ on March 06, 2009, 08:12:02 pm
Thank You so far.  i figured I should first learn about scopes before I get too much into sub-MOA and precision rifle shooting.
Title: Re: Scope School
Post by: GeorgeHill on March 06, 2009, 09:34:24 pm
Let me clarify Paralax in rifle scopes.
When shooters are talking about Paralax they are talking about the scope's reticle being on a different focal plane than the target.  So like T-man said, you get that movement.  You could put your rifle in a vice, move the position of your eye, and the reticle would look like it's moving too.  Shooting like this, you just can't get the best accuracy out of your gun.  When you focus the paralax, either with the newer style Side Focus knobs or the traditional Adjustable Objective, you bring the reticle and the target together and you can greatly reduce or eliminate that movement.  This allows the shooter to be much more precise...
All scopes have a Paralax focus.  Most are focused internally at the factory, typically on your 3-9 scopes that focal range is at about 150 yards.  Some, like say the Leupold 4.5-14 VX-III are set further, about 200 yards.  In most scopes Paralax isn't an issue until you increase the power of magnification above 9x power.  Some better glass, like Swarovski for example, it wont come into play until you get above 12 power.
Is Paralax important?  To most shooters - no.  They'd never know the difference because they act like Duffers and just crank it to the INFINITY setting an leave it there - in effect putting the scope as far out of whack as possible.  But for shooters that are going for precision - Paralax becomes important because you can't shoot with precision unless it's focused.  You can be good, you can be consistent, and do a decent job... but without a focused paralax you wont have that precision for long range shooting.
Title: Re: Scope School
Post by: FMJ on March 06, 2009, 11:48:09 pm
George, I notice that on your signature it says "LRI graduate."

I assume then you know enough about long-range shooting?
Title: Re: Scope School
Post by: GeorgeHill on March 07, 2009, 12:39:21 am
I know a bit about it.
And I'm not the only LRI Graduate here.

If you want to learn it - Go to LRI.  Let's just say that I thought I knew how to shoot before I went.
Title: Re: Scope School
Post by: FMJ on March 07, 2009, 01:03:25 am
What kind of abilities did you attain after paying them a visit?
Title: Re: Scope School
Post by: Beamish on March 07, 2009, 01:46:18 am
I know a bit about it.
And I'm not the only LRI Graduate here.

If you want to learn it - Go to LRI.  Let's just say that I thought I knew how to shoot before I went.
Didn't we all. 

The goal of the LRI's instructors is to take you and your rifle as far as you can go.  The Long-Range Hunting I class will take you to 1,000 yard shots on steel, but that is based on a broad base of skill application developed as you work up to it in 100 yard known distance increments starting with a 100 yard zero.  They will teach ranging and firing on a course of unknown distance targets (which sucks in the pouring rain with a 102 fever).  They will cover many other skills, both shooting and observing, over the 4 days.  it is well worth the trip.
Title: Re: Scope School
Post by: GeorgeHill on March 08, 2009, 03:07:51 pm
Quote
it is well worth the trip.
You will never learn more, or have more fun learning.  Especially if you get extra time for the application of learned skills exercises.
 >:D
Title: Re: Scope School
Post by: Muggins on March 08, 2009, 05:03:48 pm
Interestingly, parallax becomes an issue at close range too.  Sticking a scope with a 150 yard parallax on a .22LR will mean that the reticle will appear to move differently in your scope than targets at 50 yards appear to move.  Its even worse if you stick a "normal" scope on an air rifle.

In answer to another of your questions, the light transmission ability of a scope is dependent on a few things (the quality of the glass, the coatings on the lenses, the quality of the lens grinding, the number of lenses, etc) but the largest effect on light gathering is the size of the objective lens (the front lens).  Light enters the scope through the objective lens (the front of the scope) and passes through severl lenses on its way through the tube to your eye.  The light exiting the scope is called the exit pupil and you can see this "exit pupil" by pulling your head back from the scope and moving around to see a dot of light.  When your eye is within the correct eye relief or distance from the rear lens of the scope the exit pupil appears to fill the entire scope.  If you're too close or too far away the view won't appear to fill the whole scope ... it'll be a dot that moves with movement of your eye relative to the scope.

This exit pupil changes with magnification ... at lower magnification you have a wider field of view and a larger exit pupil, while at higher magnification you have a narrower field of view and a smaller exit pupil.  The size of the exit pupil is critical in determining how bright a scope is .... if the exit pupil is smaller than the pupil in your eye, the view through the scope will be dimmer than viewing with the naked eye.  The balance between objective size, magnification and exit pupil is all part of the black magic of scope design.  The quality of the lenses and coatings and the manufacture process is all part of why high end scopes cost more than cheapie "made in China" units.
Title: Re: Scope School
Post by: FMJ on March 08, 2009, 05:17:55 pm
Here is a follow up question:


We know that Jeff Cooper inspired the "scout" rifle concept, and these rifles rifles have scopes way forward of their receivers, why?
Title: Re: Scope School
Post by: GeorgeHill on March 08, 2009, 09:12:20 pm
While you lose precision, an extended eye relief scope mounted in that "Scout" configuration allows for faster target aquisition and engagement.  They are generally low power.  And the problem I have with most of them is that they all have too small of a field of view... which makes them not as fast as they should be.
Title: Re: Scope School
Post by: mnw42 on March 09, 2009, 11:24:26 am
I often tell people to check your zero with different magnifications.  We see this a lot around hunting season.  Guys will come out to site in their rifle and crank the magnification as high as it will go on the range.  When they get out into the field they turn the magnification down to a lower setting so they have a more reasonable field of view and discover that the bullet isn't going to the same place it was before.  They'll show up the following week to figure out why they missed or hit someplace different than their point of aim.
Title: Re: Scope School
Post by: GeorgeHill on March 09, 2009, 12:22:44 pm
That happens a lot with cheap scopes.  Good scopes, the point of zero should not change.  Now, of course you will always have changes - drastic ones - when you use a BDC type reticle, and zoom out or off of where the scope maker says you should use it... Generally at max magnification or at a set point, usually at 10 power.   This is what makes PFI scopes so bloody good - they have a first focal plane reticle, so you can zoom in and out all you like and the reticle is still smack on every time, all the time.  You also get that in a 30mm tube.  And you get those features for 1/2 of what the other guys would sell the same scope for... if they made anything like it.
Ahem... I happen to be a PFI dealer and if you want one:
https://wethearmed.com/index.php/topic,118.0.html (https://wethearmed.com/index.php/topic,118.0.html)
 ;D
Title: Re: Scope School
Post by: mnw42 on March 09, 2009, 01:00:39 pm
Oh, I've seen more than a few $100 dollar scopes on $700 rifles :banghead  If that is what you afford, it is what you can afford, but most people are just cheaping out on glass.  The old adage: "Spend as much on the scope as you did on the rifle and more if possible"  is as true as it ever was.

I have a cheap Bushnell on my .22 - it is what I could afford at the time, but I will upgrade when possible.
Title: Re: Scope School
Post by: GeorgeHill on March 13, 2009, 09:46:46 pm
RIFLE:  Kimber 8400 Classic, .300 WSM.  A thousand bucks.
SCOPE:  BSA Cat's Eye.   Fifty bucks.

Showing everyone in the Gun Store how much of a moron you are - Priceless.

Title: Re: Scope School
Post by: Thernlund on March 14, 2009, 03:51:27 pm
I have a buddy who bought a Colt AR recently from one of the only shops that still had them.  He was hot to put a red-dot on it ASAP.  At the next gun show he promptly bought two NcStar red-dots for the amazing price (so he thought) of $20/ea.

When he told me I about flipped.  I had given him some advice on decent optics to use, but he saw these and didn't want to wait for mail order.  Ugh.  ::)

I told him not to put that NcStar on the AR, at least not in public.

Now I'm the a__h___ for some reason.  >:(


-T.
Title: Re: Scope School
Post by: Outbreak on March 14, 2009, 09:02:29 pm
I told him not to put that NcStar on the AR, at least not in public.

Now I'm the a__h___ for some reason.  >:(


-T.

No, the real a__h___s are the designers at NcStar. Not only are those scopes cheap, they're uglier than sin!
Title: Re: Scope School
Post by: GeorgeHill on March 14, 2009, 09:38:17 pm
Trying to get people who are uninformed into good glass is frustrating.  Because the uninitiated who don't know how to look through glass, wont know the difference.  Glassing is actually a learned skill.  Be it Binos, Rifle Scopes, or Red Dots.   If they can't see the differences, they wont see anything but the price and that's all that is going to matter to them.
Quite simple - no matter what it is - if it's less than 150 bucks it probably isn't worth having. 
At 200 bucks it becomes decent.
At 300 bucks you start getting into good glass.
At 500 bucks you start getting into great glass.
Title: Re: Scope School
Post by: FMJ on March 14, 2009, 10:15:49 pm
What to look for then?

 Only time I ever looked through glass was once when I used a SuperRedHawk in .44 Mag.  It had a scope mounted directly over the barrel.  Since we were shooting many guns that day I never really payed attention to the brand of scope nor what magnification it was.  I was so excited shooting a .44 Mag for the first time I forgot to ask.

 
Title: Re: Scope School
Post by: GeorgeHill on March 14, 2009, 10:32:54 pm
Go start looking through glass.  Pick a brand... say Nikon.  Start at the cheapest and start looking through it at each price level.
You'll start to see.
Title: Re: Scope School
Post by: FMJ on March 14, 2009, 10:45:27 pm
Looks like I need to get myself a good rifle then.
Title: Re: Scope School
Post by: GeorgeHill on March 14, 2009, 10:47:45 pm
Of course you do.

But I'm not talking about just rifle scopes.  I'm talking about anything optical.  Binos.  Rangefinders.  Spotting Scopes.  Celestial telescopes.
Good optics are always worth it.
Title: Re: Scope School
Post by: Outbreak on March 15, 2009, 02:59:01 am
I consider myself lucky that I don't have a good rifle to mount glass on. :neener

Actually, I'm taking George's advice on red-dots for my AR. I'll get something with my bonus check (read "desert money") when I get back from the deployment.
Title: Re: Scope School
Post by: FMJ on March 15, 2009, 09:21:28 pm
Outbreak, are you on active duty right now?
Title: Re: Scope School
Post by: GeorgeHill on March 15, 2009, 09:51:54 pm
He is.
Title: Re: Scope School
Post by: FMJ on March 15, 2009, 10:02:53 pm
In-country?
Title: Re: Scope School
Post by: Outbreak on March 16, 2009, 05:40:11 am
Active duty, yes. If you mean in the US, then yes. I'll be deploying soon.
Title: Re: Scope School
Post by: FMJ on March 16, 2009, 12:33:53 pm
Good luck with that.
Title: Re: Scope School
Post by: Tom The Impaler on March 23, 2009, 07:50:46 pm
You can learn a LOT about basic optics at astronomy websites. For instance,

Resolution, the smallest detail you can see, is dependent on the objective diameter as much as the magnification. I can see a 22 baliber hole at 100 yards through my Meopta 3-12 X 50 at 12X, I haven't tried it at lower power. Mount Palomar doesn't list it's scopes by magnification, it lists them by objective diameter for this reason.

Larger objective diameter also brings in more light and is thus better for dawn and dusk shooting. light transmission varies inversely with magnification. The image darkens as the magnification goes up. So if you're hunting dusk or dawn run the magnification to it's lowest setting.

So a 20 X scope with a 32mm objective is a joke, if you want a high mag scope you need a large objective too or you're shooting in the dark.

Until I bought a Meade ETX 90 Maksutov Cassegrain and studied astronomy I was really clueless about optics.

http://www.meade.com/etx_premier/index.html (http://www.meade.com/etx_premier/index.html)

Title: Re: Scope School
Post by: GeorgeHill on March 23, 2009, 08:24:54 pm
Quote
Larger objective diameter also brings in more light and is thus better for dawn and dusk shooting.
Oh man... here we go again!   This is true in theory.  If all other factors are equal... that's right.
But don't take objective size as a determination of quality of light transmission.
A bigger lens has the potential to transmit more light.  But we see quite often smaller yet higher quality glass have better clarity, brightness, and "resolution" than cheaper larger glass.
If you don't believe me - just go look for yourself.  Look at a 50 mm Buckmaster and look at a 40 mm Zeiss.  You'll see the difference.
The lens coatings play such a huge factor and this isn't something that you can just quantify. 
You get what you pay for - this holds more true with optics than anything else.
Title: Re: Scope School
Post by: Tom The Impaler on March 23, 2009, 08:30:24 pm
Oyvey! fair enough! I should have said "All other things being equal"!
Title: Re: Scope School
Post by: GeorgeHill on March 23, 2009, 11:37:45 pm
LOL, no worries.
The problem with the Optics industry is that it plays on the ignorant.  Because there is no way to quantify optical quality.  You can't just use a light meter, because that wont rate clarity.  Then there is other factors such as parallax and color transmission. 
Now, Swarovski is easily the best glass you can buy when it comes to optical quality... those cats throw down coatings that actually focus and tune the colors that come through.  (HD series) I mean - come on!  That's some hard core optical science right there.
Unfortunately I would not put one of those scopes on a gun heavier recoil than a .30-06 because Swarovski just isn't strong enough.
Now theres another factory Recoil Tolerance or simply "Strength".  Without strength, your optical quality is useless.
You could have a great clear scope - and it goes and craps the bed when you need it the most.  I've seen a lot of scopes do this... I remember we had 7 Swarovski's in one deer season at our location.  No, I'm not kidding.
Sure, those scopes were all repaired under warranty, but that left those hunters scopeless for awhile.  Not cool during our short hunting seasons.
Then there are features you might want, reticle patterns, turret styles, side or objective focus adjustment... main tube diameter... objective diameter... weight of the scope.  There really is no ONE scope that outshines all others... because your Mission and your Requirements are going to do be different. 
So you guys have got to arm yourself with say, 5 requirements.  Now when you look at scope options, be ready to drop one or two requirements to find the right scope for your job and for your gun.   You can have a great scope - say, a Nikon Monarch 6.5 to 24 with a 50mm... great scope for the money.  But you want to put that on a CZ 527 Carbine?  Nope.   Great scope - but not a good match for the gun.  See what I mean?  Or for example, I like my 2-7x32mm Vortex Viper... great scope... but put it on a .300 RUM?  Nope.  Now let's swap those scopes on these rifles, and we have better fits for the rifle's missions. 

I have to admit something there... I'm finding that I'm polarizing between two brands.  Nikon for the value, Zeiss for the top quality.  I'm also a HUGE believer in that Rapid Reticle system.   Be it from Zeiss or from PFI - or Swaro's BR reticle.  That is the way to go.  I don't even like using a standard plex anymore.
Title: Re: Scope School
Post by: Tom The Impaler on March 24, 2009, 06:05:18 am
You've brought up an issue I can't recall the reasons for.

Tube diameter.

why 1" or 30mm? does the extra diameter give you some rigidity? extra clicks of vertical/horizontal adjustment?
Title: Re: Scope School
Post by: Beamish on March 24, 2009, 09:06:10 am
You've brought up an issue I can't recall the reasons for.

Tube diameter.

why 1" or 30mm? does the extra diameter give you some rigidity? extra clicks of vertical/horizontal adjustment?
The same reason you have a larger objective: light transfer.  Imagine trying to look through a dinner plate sized objective lens with the tube body of a straw.
Title: Re: Scope School
Post by: GeorgeHill on March 24, 2009, 09:57:31 am
I'll get back to this tonight... no time to explain it in detail.  At work.
Title: Re: Scope School
Post by: GeorgeHill on March 24, 2009, 10:51:09 pm
You've brought up an issue I can't recall the reasons for.

Tube diameter.

why 1" or 30mm? does the extra diameter give you some rigidity? extra clicks of vertical/horizontal adjustment?
Okay, real quick... One of the other things a fat tube does for you, especially with big objectives is that it helps keep the light from diffusing.  I don't know how else to explain that.  When you bend the light from a 50mm obj and force it to funnel it through a 1 inch tube - you get that brightness, but your working the light too hard and it diffuses.  A 30mm tube doesn't let the light diffuse as much.  What this variable works on is clarity. This allows you to have greater clarity.   To see this for yourself, take a look through the Leupold 4.5-14 VX-III with the 1 inch tube, and the same scope with the 30mm tube.  You will see that you have a better field of view, with sharper clarity. 
Title: Re: Scope School
Post by: Beamish on March 24, 2009, 11:25:00 pm
Well, sure, if you wanna be all scientific about it.  I thought my straw and dinner plate metaphor worked well.   :neener

(Role reversal anyone?)
Title: Re: Scope School
Post by: GeorgeHill on March 25, 2009, 12:00:14 am
 :clap
Well played, Sir.
Title: Re: Scope School
Post by: Tom The Impaler on March 25, 2009, 12:18:00 pm
I poked myself in the eye with the straw, and it didn't magnify anything. ;D
Title: Re: Scope School
Post by: GeorgeHill on March 25, 2009, 06:03:28 pm
I poked myself in the eye with the straw, and it didn't magnify anything. ;D
Oh, you have a Bushnell scope?
Title: Re: Scope School
Post by: Tom The Impaler on March 25, 2009, 06:18:58 pm
Ha Ha!

Title: Re: Scope School
Post by: Tom The Impaler on March 25, 2009, 06:20:17 pm
Oh, you have a Bushnell scope?


Hey it's a tacticool Scope though.
Title: Re: Scope School
Post by: Outbreak on March 26, 2009, 02:47:18 pm
Oh, you have a Bushnell scope?


FTW!
Title: Re: Scope School
Post by: FMJ on March 29, 2009, 02:25:31 am
Due to all the information on this thread (about parallax, and tube diameter, etc.)  I'd like to nominate it for a sticky.  What do the mods think?
Title: Re: Scope School
Post by: Thernlund on March 29, 2009, 05:53:15 am
Done.


-T.
Title: Re: Scope School
Post by: Mumbles on June 14, 2009, 09:36:10 pm
Quote
why 1" or 30mm? does the extra diameter give you some rigidity? extra clicks of vertical/horizontal adjustment

Quote
The same reason you have a larger objective: light transfer.

I don't want to say that is incorrect, but it is not completely correct.  Light might play a small role, but the primary reason for a thicker tube is greater erector travel.  Objective size and coatings are the primary factors in light.
Title: Re: Scope School
Post by: FMJ on June 23, 2009, 03:09:17 am
How does scope mounting on a rifle work?

Also, I notice that nowadays, there seems to be 1913 rails instead of scope mounts.  Are the rails more practical? Do they help the scope hold its point of aim?

I'm sorry I constantly ask so many questions here on WTA, but what can I do?  I'm not going to go learn stuff from COD 4.  Not in the real world.
Title: Re: Scope School
Post by: Mumbles on June 23, 2009, 03:36:01 am
You mean what is the proper way to mount a scope?  I use feeler gauges like you would get in any car parts store, stick them between the flat on the turret housing and the rail as you tighten the ring caps down.

Title: Re: Scope School
Post by: Thernlund on June 23, 2009, 03:39:11 pm
I'm sorry I constantly ask so many questions here on WTA, but what can I do?  I'm not going to go learn stuff from COD 4.  Not in the real world.

That might be the happiest thing I've heard this week.  *tear*


-T.
Title: Re: Scope School
Post by: Harm on June 23, 2009, 04:40:48 pm
I've got nothing much to add to this since I know SO much about scopes and all  :devillol


BUT I did need to point out a correction for T:
Quote
The lack of parallax is how cinematographers achieve "forced perspective".  That is, placing one object further away than another in order to make one appear smaller that the other.  This technique was used to great effect in Lord of the Rings.  If however the camera had moved in the scenes where forced perspective had been used, the effect would have been blown as you would have seen the two objects move differently in relation to each other as the perspective changed.

Not quite accurate.  It used to be, but with motion controlled sets they were able to use forced perspective AND change the camera positioning.  So it's all about manipulation.  I studied film and theater in College.  Thats my arena.  Had to toss that out there.  If you'd like to see what I'm talking about the Making of Video's on the Extended Directors Cuts of The Fellowship and The Two Towers both address this technique.
Title: Re: Scope School
Post by: Thernlund on June 23, 2009, 04:42:53 pm
:hmm

Good to know.


-T.
Title: Re: Scope School
Post by: Harm on June 23, 2009, 04:53:33 pm
T when you watch it you'll see what I mean.  Literally the sets were machines that came apart and shifted perspective with the camera's motion to then reset for a different perspective. 

As an aside forced perspective can be seen anytime gandalf is interacting with the hobbits.
Title: Re: Scope School
Post by: FMJ on June 23, 2009, 07:08:59 pm
Well, I meant to ask how are the scope rings actually out on receivers.

I've heard of X gun that comes with a drilled and tapped receiver, for example.  Does that mean that you screw the rings directly onto the receiver?
Title: Re: Scope School
Post by: Mumbles on June 23, 2009, 07:56:33 pm
Generally speaking, you screw the scope base into the receiver.  Sometimes, like with a Surgeon action, the rail and receiver are all machined out of the same piece of metal.  There are various styles of scope bases: Picatinny, Weaver, Clip Slot, various sizes of dovetail, etc.  Picatinny and Weaver are nice because they prevent the scope from sliding forward under recoil, and give you a reference point for remounting if you remove the optic.  On rifles intended for long range shooting, the base is frequently canted forward to prevent you from burning up a lot  of the erector travel just getting the scope zeroed, not leaving you much room for adjustment for dialing elevation. 
Title: Re: Scope School
Post by: JesseL on June 23, 2009, 08:03:50 pm
Well, I meant to ask how are the scope rings actually out on receivers.

I've heard of X gun that comes with a drilled and tapped receiver, for example.  Does that mean that you screw the rings directly onto the receiver?

Sometimes rings are screwed directly to the receiver. I've only personally seen this on a Ruger 10/22.

Other times scope bases are an integral part of the receiver; whether the 3/8" dovetail common on .22s, Ruger's proprietary system, Weaver/Picatinny 1913, or something else entirely.

More often some sort of bases are screwed to the receiver, which then has the rings mounted to it. There are all sorts of base systems, but the most popular these days is of course the Weaver/Picatinny 1913 style.

The  Weaver/Picatinny 1913 style uses a dovetail rail with cross slots. The rings clamp to the rail with screws that pass through the slots to resist shifting under recoil. It's a good idea when mounting rings to this kind of rail, to push them forward as they're being tightened so that the cross screw contacts the forward side of the slot to avoid shifting the first time the rifle is fired.

Another popular base system is the Redfield style which uses a twist in dovetail for the front ring and wedges the rear ring between a pair of screws that can be adjusted for windage:
(http://media.basspro.com/images/articles/ScopeRingsBases0609_022.jpg)
(I personally hate these and hope they go away)



Title: Re: Scope School
Post by: Mumbles on June 23, 2009, 08:28:40 pm
Quote
The  Weaver/Picatinny 1913 style uses a dovetail rail with cross slots.

Just to clarify, these are not the same thing.  Very similar in appearance, and sometimes you can get away with interchanging systems, but not the same thing.
Title: Re: Scope School
Post by: chiwar7178 on June 26, 2009, 08:44:03 am
(http://media.basspro.com/images/articles/ScopeRingsBases0609_022.jpg)
(I personally hate these and hope they go away)
AMEN!
Title: Re: Scope School
Post by: cpaspr on November 13, 2009, 04:39:47 pm
Okay.  I have to ask.  Why is that particular style so hated?

The reason I ask, is that I need to add a base to a K98 Mauser action (now chambered in 30-06).  There is already one screw hole drilled in the back for the current scope base setup (something wierd from about 1950 - Willson or Wilson, I think) which houses a Kollmorgan 26mm tube, 4x scope.  The current base has two screw holes in the front, but they're side by side, not in line.  We intend to re-use the rear hole, and plug the current front holes and drill and tap new ones.

It's been recommended that I get a Leupold one-piece base, which looks just like the dreaded one in the picture.
Title: Re: Scope School
Post by: JesseL on November 13, 2009, 04:53:29 pm
Okay.  I have to ask.  Why is that particular style so hated?

1. It leaves the front ring doing most of the work.
2. I feel that using the windage knobs on the rear ring puts unnecessary stress on the scope tube.


If I were you, I get a base like this (http://www.midwayusa.com/viewProduct/?productNumber=364040), and a couple of these rings (http://www.midwayusa.com/viewproduct/?productnumber=416175).
Title: Re: Scope School
Post by: cpaspr on November 14, 2009, 02:14:25 pm
Thanks Jesse.  That makes sense.  No disrepected intended, as I can understand your point.  I just hate the looks of Picatinny style rails on hunting rifles.  Are there other bases that aren't so Picatinny-esque?
Title: Re: Scope School
Post by: JesseL on November 14, 2009, 02:46:27 pm
No offense taken. I agree with you, Picatinny rails don't look right on hunting rifles.

You can get some two piece weaver bases (http://www.midwayusa.com/viewProduct/?productNumber=580717). The classic problem with two piece bases is alignment. If they're not mounted perfectly, the rings won't line up perfectly, and the scope gets tweaked. The spherical bushings in the Burris Signature rings make that less of an issue.

That's exactly the setup I used on this Mauser:

(http://i100.photobucket.com/albums/m5/J_M_Lambert/Guns/100_3304.jpg)
Title: Re: Scope School
Post by: cpaspr on November 16, 2009, 04:53:51 pm
Thanks Jesse.

That looks a lot like my setup, except mine has a stainless bull barrel and a plain jane composite stock.  (I think.  I guess I haven't really paid that much attention to the stock.  It holds the action and the barrel, and it's black plastic, so I really haven't noticed if it has the checkering moulded in.)

The reason we (the friend who is helping me with this) were going to use a one-piece base is that the rear mount hole is already available.  The Williams (or Wilson, whatever) current setup is two piece, but the rear mount only has one screw.  We were going to fill the two side-by-side front mount holes and re-drill in-line for the one-piece mount.
Title: Re: Scope School
Post by: bmitchell on January 05, 2010, 11:13:45 am
I recently picked up a good deal on a Savage 11 in 300WSM and I'm looking at 1" scopes to fit the two piece rings I've got coming.
MadOgre's scope comparisons are helping a ton but right now what I'm trying to decide is whether to go with the Nikon ProStaff now or wait a while and get a Leupold VX-II.  What are y'all's thoughts?
Lapping and alignment of two-piece rings?  The ones I've got on the way are some Talley Light rings that are both base and ring in one solid piece.

Ben
Title: Re: Scope School
Post by: bmitchell on January 06, 2010, 01:00:45 pm
Talked to the Ogre today.  He gave me a rundown on the Leupold prices Basin Sports has and steered me toward a Zeiss Conquest.

Ben
Title: Re: Scope School
Post by: Survivalized on September 16, 2010, 01:35:34 pm
I'm interested in attended and LRI course next spring some time, but I can't seem to find a website or anything for them. Any of you guys know where I can find scheduling and pricing info for them?
Title: Re: Scope School
Post by: Garaballo on September 16, 2010, 02:43:37 pm
Last time I asked Little Lebowski about it, he didn't send an answer back, their site is down last time I checked so maybe LL's brother is in deployment/ folded the company, who knows, it's meere speculation, Ogre's link to the L.R.I. forums gets me a blockpage.cgi, but I'm at work right now, so might as well check later.

Question, I have a rifle with 11mm dovetails, I have a scope with a certain diameter, what's the measure that matters when buying a pair of rings for a scope?, let's say I have a Bushnell Banner 4x32mm scope, should I measure the Ocular lens's tube diameter and then the base rings distance between the ring's contact surface with the base to the center of the rings? what about cheek weld? If the scope would sit too high, is there any other way other than adding pads to the stock?
Title: Re: Scope School
Post by: Thernlund on September 16, 2010, 03:13:00 pm
I'm interested in attended and LRI course next spring some time, but I can't seem to find a website or anything for them. Any of you guys know where I can find scheduling and pricing info for them?

I don't think LRI is currently operating.  I couldn't guess as to whether that's a permanent situation or not.


-T.
Title: Re: Scope School
Post by: Survivalized on September 16, 2010, 06:14:42 pm
Bummer.  :hmm
Title: Re: Scope School
Post by: ksuguy on September 16, 2010, 06:49:03 pm
I don't think LRI is currently operating.  I couldn't guess as to whether that's a permanent situation or not.


-T.

I've also heard good things about the long range courses at Badlands Tactical in Oklahoma.   However, I haven't taken any classes there, so I can't personally attest to their quality.

http://www.badlandstactical.net/home.htm (http://www.badlandstactical.net/home.htm)
Title: Re: Scope School
Post by: Tom The Impaler on November 28, 2011, 08:05:06 pm
Here's a nice question, Is there a valid way to test or examine scopes indoors? I've now spent good money on what I think to be a good scope, a Bushnell Tactical 6-24X50. I think it's pretty decent because I can readily spot .308 holes in paper at 150 yards, but there's no way to know that shopping inside a store is there? Or is there? Can resolution be checked within the confines of a shop? Or light transmission?
Title: Re: Scope School
Post by: Thernlund on November 28, 2011, 08:08:03 pm
Generally if you stick to brands you know, you'll be fine.

I know quite a few stores (the local Cabela's here does this) put an eye chart on a far wall so as to allow the customer to test the optic.

They even had a rifle stock with little foam rubber "rings" that you could pop the scope in and out of to test.


-T.
Title: Re: Scope School
Post by: Panhead Bill on November 28, 2011, 08:51:43 pm
Ok, I'm relatively new to the whole scope thing, but I'm glad I came across this thread, and a few other scope-related threads on WTA recently, as I almost bought a $70.00 scope at a chain sporting goods store a couple of weeks ago.  A LOT of info I'm trying to process on scopes here, and I'm still not sure why exactly the cheap ones are bad, except I get that they are not good.   :shrug

I'm not out long-distance hunting (for now), I just want to be able to see what I'm doing at the range at 100 yards with my Mini-14.  But granted, I do want consistent accuracy when I do my part.  Hell, back in the Corps I was hitting well at 500 yards and iron sights, but now my older eyes I can barely see the man-sized silhouette at 100 yards.  I can hit decent sized groups with iron sights at 100 yards, but I would like to try it with a scope (never used one before - and I'm kind of sick of walking down range every 10 rounds to see where my shots are.  (I tried a pair of cheap binos I had floating around but I still couldn't see the .223 sized holes). 

I can't afford much (hence why I was even looking at a $70 scope), and the Mini-14 didn't cost me anything (so the scope costing the same as the rifle doesn't help any), so I'm trying to figure out what's a reasonable price range to spend on a scope for it, when it's more or less for plinking, although I'd like to get more out of it in the future. 

Any suggestions on where I should start looking?  Or do I wait until I can afford a $500+ scope and live with the iron sights and walking to see my POI until then? 

Bill
Title: Re: Scope School
Post by: Tom The Impaler on November 28, 2011, 10:58:13 pm
Well, as to why cheap is bad, I got the $50 cheapie Bushnell for my Ruger 10-22, ran about 200 rounds through it, and the reticle broke loose. I could tell because the groups moved from 2" at 85 yards at my range to "where the hell are they going?!". Mind you Wal-Mart replaced the scope free of charge but still.....

Also as you spend more for better quality you'll get better resolution (see above) and as your eyes get older you'll definitely appreciate it. You can still get decent optics without breaking the bank, just don't ask for too much for too little, and know that the $50 Bushnell is made in the same plant as the NC star probably is, better money buys better lenses, coatings, and sometimes waterproofing. you'll have to look carefully at the specs. Expectations play a big part in satisfaction. An easier cheat is to look at the reviews of the scopes at online retailers

To give an apples to apples comparison to the above, My 10X40 tactical Bushnell ($200) has helped me put 5 bullets into 1/2" at 100 yards with my .308, and the scope which replaced it, another, $700+ model tactical, can spot .308 holes at 150 yards, which the other couldn't, pretty nice.

A rule of thumb used often is to spend as much on the optic as the gun it goes on, that can be really hard to do as the price of the gun goes up, but I can't completely refute the statement. For your Ruger Mini 14 for instance, durability trumps clarity, as the mini 14 isn't known for it's accuracy, but ALL centerfire semi autos are well known to abuse scopes. My ROMAK AK gutted a Trijicon Tri Power same as the Bushnell mentioned above. The difference in that case? No retailer returns, I sent it back to Trijicon and they replaced it free of charge. pretty nice for an optic that pricey. So my advice would be to go Trijicon if you can afford it, or another premium red dot or low magnification scope, such as The Leupold tactical prismatic 1X.
Title: Re: Scope School
Post by: Tom The Impaler on November 28, 2011, 11:10:02 pm
As I thought, another thing appears as the price moves up. Bells and whistles. along with the coatings and waterproofing and the fine crosshairs, eventually you'll get Parallax adjustment, or focus it's sometimes misnamed. For under $200 it's essentially non existent in a quality scope, For $200-$500 it's on the bell, or objective end, and above $500 it's typically on the left side of the scope opposite the windage knob for adjustment without bringing the gun out of battery. again for the Mini 14 parallax is a non issue really, most non adjustable scopes are set to 100 yards but for a non benchrest/precision gun the errors of the gun and ammunition far outweigh the parallax errors.
Title: Re: Scope School
Post by: ammo1738 on November 29, 2012, 08:08:01 am
I recently received a Savage model 99 in 300 cal. due to a death in the family. I want to put a scope on this rifle but it is so old I do not want to drill into the medal. I was told to look up a Stith mount. These run anywhere between 150.00 and up. Is there an aftermarket mount that is cheaper and still will not have to drill into the metal?
Title: Re: Scope School
Post by: JesseL on November 29, 2012, 12:21:54 pm
I recently received a Savage model 99 in 300 cal. due to a death in the family. I want to put a scope on this rifle but it is so old I do not want to drill into the medal. I was told to look up a Stith mount. These run anywhere between 150.00 and up. Is there an aftermarket mount that is cheaper and still will not have to drill into the metal?

Definitely don't drill and tap it.

I don't know of another mount other than the Stith that will work on an older 99 like that, so your choices are pretty much the Stith or learn to love the iron sights.

Personally, I'd choose the latter. If you really want a scoped rifle there are plenty of good options available that will probably shoot better and won't require altering an heirloom and potentially valuable vintage rifle.
Title: Re: Scope School
Post by: mjelsik on June 16, 2014, 03:26:36 am
FWIW: You can have a $4k precision rifle capable of laser beam accuracy, but top it off with a crappy scope, and your not going to hit or see anything. Your optic is THE MOST important component on your rifle. You don't have to have a "tactical style" scope to have good glass, but you do want turrets that track 100% accurate and hold/return to zero. Sometimes you have to educate yourself to help sift out the B.S. that scope marketers throw out there... I have Vortex Vipers or higher on all of my rifles because it is the best value for my hard earned money, my scopes track right, are clear, and have features that give me that edge on the hunting trip...

Take a few mins to watch this:

https://www.youtube.com/watch?v=CX3hLSI59ko (https://www.youtube.com/watch?v=CX3hLSI59ko) (scope quality by brand)

Your welcome!