What do the Scope Numbers mean? Help! :)

Mercury

Another "newbie" question. As I said in previous posts, where I grew up in Missouri, scopes were never needed, or used. I can't remember anyone having a scope on their rifles.

So, I know absolutely nothing about scopes.....what do the numbers mean? I think that the higher the number, the better? I'm not really sure.

Thanks in advance for your help, this is the most helpful forum I've found!


Merc

NO! You may not have my guns! Now go crawl back into your hole!

He Dog

Numbers, you mean like 3-9x40? It means that the scope is a variable with the magnification adjustable between 3 power and 9 power, and that the objective (the front lens) is 40mm in diameter. A 4x28 is 4 power or magnifies 4 times and has a 28mm objective. You can take it from there...

Actually, I should have pointed out that those numbers are important in figuring out if the scope is suitable for what you want a scope to do. If you are hunting varmints at long range you are more likely to need a scope of 4.5-14x than a scope of 2-7x. If you are hunting in deep woods and likely to see game just after day light or just before sunset, you probably do not want a 3-9x32 scope because it will not transmit as much light as a 3-9x40 scope.

I you are really interested in hunting optics, I suggest Optics for the Hunter , by John Barsness. There will also be a new book out this month from Krause on hunting optics by Van Zwoll which is also likely to be good.





Edited by - He Dog on 04/15/2002 16:38:12

Mercury

He Dog,
So you want as large objective as possible? Does light figure into it any way?

Merc

NO! You may not have my guns! Now go crawl back into your hole!

aglore

Which numbers? Power settings, model numbers? Tube diameter. Objective lense size?

AlleninAlaska aglore@gci.net

How would you rather die, 10,000 foot pounds of muzzle energy in the BUTT or a sharp knife in the HEART?

He Dog

Mercury, like most things in life, there are trade offs and compromises. In Europe where they often hunt legally at night huge objectives (56mm +) are common. The price is that you need tall rings to lift that scope off the barrel, requireing a more head up shooting position than most Americans are used to. That generally means compromised accuracy. The trick is to figure out how the scope will be primarily used and in what condtions most commonly. Then pick a scope best suited to those needs. Because we often try to make one or two rifles do it all, rather than having several purpose built rifles or rifles with single purpose scopes, the variables have become common. For big game hunting, you can do just fine for a life time with a good 4x or 6x scope. The variables have become common because the can be used at a variety of magnifications, though most get set and are seldom moved.

If you are starting new, get the best (which generally means most expensive) scope you can afford. In optics you get what you pay for. I would suggest Nikon Monarch, Burris Signature or Weaver Grand Slam. Take a look at www.bearbasin.com for good prices and service.

badboybob

Also for low light shooting you need a scope with an "exit pupil" of 7mm or greater. That's easy to figure, just divide the scope's diameter by the power, i.e. 6X40=exit pupil 5.5, not good enough for twilight shooting. This is where a variable power scope may your best choice. 3-9X32= 10+ exit pupil at 3 power, very good for low light. 3-9X40 is a waste of money at 3X power, but ok at 5X power. The same rule applies to binoculars. 10X50 are worthless at night, but great for watching bikini clad babes

PC=BS

Edited by - badboybob on 04/15/2002 16:08:25

He Dog

Generally that is true, but your pupil only dialates to 7mm when you are quite young, and by 30 you are past that, at which time you will have more light than your eye can take in anyway. By 50, with good eyes, you are unlikely to have a pupil dialation greater than 5.5 or 6mm

The Bad Boy derived the exit pupil by dividing the diameter of the objective by the magnification, in case you did not figure that out.


Edited by - He Dog on 04/15/2002 16:23:46

badboybob

Hey He Dog I didn't know that. No wonder I can't see sh**t after dark any more (66 now)


PC=BS

He Dog

The large exit pupil is still useful at times, even if there is more light than you can use, because sometimes that is the only way to peer into some really dark woods areas. Generally though, huge objectives are not worth the compromises. I have a scope with a 56mm objective a friend in Sweden sent me. Looks serious, but raises my cheek way too high for good shooting.

You are only a few ahead of me Bob, so that makes two of us