50mm Objective vs. 40mm

Curly

I found a rifle I like on the internet and it has a 50mm Objective lens scope mounted on it. I have always used 40mm scopes and am wondering about the 50mm working.How important is it when you shoulder a rifle that your cheek is touching the stock? I am assuming that with the 50mm setup, I would have to raise my head off the stock to be lined up through the scope. I am looking for opinions from people who have 50mm scopes or have shot them. I never have. Thanks in advance.

whiteclouder

You have stated the primary reason for most scopes being 40MM, the rifle stocks are designed for them. You must seat your face on the stock for consistent accuracy. And you must seat it in the same place every time. The ONLY reason we are seeing 50mm scopes is becasue they can be touted as NEW and STRONGER, marketing, marketing, marketing. Some here will say the extra 10mm will gather a lot more light and they are right. But if you have to work that much to gather light you are shooting when you probably shouldn't be. The 40mm has served us well since the 30's. Stay with it.Clouder..

will270win

If'n they tell ya it gathers more light then you got lied to. Coatings and low power gather light. I have no problem with the "head off stock thing" probably cause I got fat cheeks and I'm a little taller than most folks. I figure 40MM is just as good as anything else so if they do you good, stay with 'em. I would if I didn't have all these dang 44's and 50's.

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Eat healthy, exercise, avoid smoking........Die anyway. will270win@aol.com ~Secret Select Society Of Suave Stylish Smoking Jackets~

idsman75

I have found that the way to find out which scope gathers most light is to test them out at sunset. Go to the sporting goods store and ask them to take a few models outdoors. Ironically, Nikon performed better than Leupold when I did this and look at the price difference. Nikon transmits more light and costs less.

will270win

I like Nikons, too.

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Eat healthy, exercise, avoid smoking........Die anyway. will270win@aol.com ~Secret Select Society Of Suave Stylish Smoking Jackets~

ysacres

Correct me if, But Nikon only makes a 44mm tube, Leupold makes 50mm. I own two of each. for your buck Nikon has the best optics. To see the lite at the end of the tunnel the Leupold 50mm shines.

Xracer

will.....you're flat-out wrong. A 50mm objective will pass more than 2x the light of a 40mm one.Coating has nothing to do with light gathering, but rather prevents flare and internal reflections in a multi-element scope.Most newer 'scopes now contain Low Dispersion glasses which help prevent light falloff at the edges of an image, which makes current 40mm scopes appear brighter than they did a few decades ago. Whether or not you want something brighter still, is up to you.If you have more than 3/16" clearance between the front of your 'scope and the barrel, and can use the same scope mount you have now, your eye height will be no more than 3/32" higher with a 50mm objective.

varmit hunter

The human eye can only reseve 7.5 MM of light,And that is in a young person.They are not puting light in your eyes,They are taking money out of your pocket.

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A unarmed man is a subject.A armed man is a citizen.

Guns & Glass

There are some big advantages of 50mm and even larger scopes, and some even disavantages.++: Larger exit pupil=see target faster.++: About 35% more light=brighter,see in low light better.++: Sometimes sharper. Depends on scope.--: Higher mounting=poor stock "weld", and can increase "felt recoil".--: More $$. Might not be worth it.Many rifle stocks are made today to use a 50mm scope, as the stock comb is higher. but that depends on your body.When hitting about 50 yrs. young, the eye can need almost twice (2X) the light that it did at 25 yrs. young. So, depending on your age, or how long you want to keep a quality scope it can all be worth it.Scopes transmit light. Not gather it. There aren't little invisible arms sweeping light into the glass. Neither does power(magnification), or coatings. Now, how well it transmits light is so important.You don't mention what kind of scope it is. You can look at a 50mm low quality scope, and not see as good as a 40mm scope. You can look at the same quality model 40mm, and 50mm scope, by the same mfr., and in low light the picture is brighter , but the sharpness isn't better. But if made right, a 50mm will help you see better, and will be sharper.There is a lot more then slapping a larger lens in a scope to make it see better. But done right, a 50mm scope will help. [This message has been edited by Guns & Glass (edited 01-07-2002).][This message has been edited by Guns & Glass (edited 01-07-2002).]

dakotashooter2

If I recall, and someone may have to help me out because my memory is slipping, the brightness of a scope is relative to, the size of the objective, power of the scope and as varmint hunter stated the maximum amount of light the human eye or pupil can process, which I thought was more in the neighborhood of 3.5-4 mm. Divide the objective size by the power.I forget the terminology but the number you get is how much light is transmitted by the scope. If that exceeds what the eye can process then you either increase the objective size or lower the power to achieve maximum brightness. For example for a 40mm objective you reach your maximum brightness at 10X. Anything more will reduce light transmitted anything less will transmit more light than the eye can process.For a 50mm objective the number is roughly 12X. This is why you see most standard size binoculars in 8x30 or 35, 10x40 or 42 and so on. Lens coatings can effect this to some extent but are more related to clarity.

He Dog

Will, all other things being equal the 50mm will transmit a little more light than a 40mm. However it is very difficult at best to be sure all other things are equal. If you are planning to hunt with this scope 40mm is likely to serve you well. I agree with Clouder that 50mm is not needed unless you hunt in Northern Europe or hunt at night. You are better off with a lighter scope for all day carry, and keep the magnification low. 3-9's and higher are pretty standard these days, but for almost any hunting situation a maximum of 6x will serve you fine. I tend to buy the 1.5-6x variables or something in that range, but a fixed 6x or even 4x will do the job. This is a telescopic sight to target game. You are not counting the fleas in his ears or admiring his fine antlers, you are trying to put a bullet in the boilerroom and you do not need 14x to do that. In fact at higher magnifications it is harder not easier to get on target. Stick with your 40mm or 44mm scope, and if buying a new one put your money into the best quality you can afford, not the biggest.

7mm_ultra_mag_is_king

I got one question, can you see a groundhog, or prairie dog(depending on where you live) at 500+yards with that 1.5-6x scope?? I sure cant. I have trouble spotting them at 300 yards with a 16x.

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when all else fails........................

will270win

Whatever ya'll say. I don't really care. My pentax 39MM WILL PULL MORE LIGHT THAN ANY OTHER SCOPE I HAVE SEEN. The Nikon will do nearly the same. If'n there's a real explanation then let me know. Maybe it's a per capita thing.

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Eat healthy, exercise, avoid smoking........Die anyway. will270win@aol.com ~Secret Select Society Of Suave Stylish Smoking Jackets~

He Dog

Nope the 6x will not do the job hunting rodents. For that you do indeed need higher magnification. I just figgered he was huntin' real he-man stuff like deer and elk.

whiteclouder

And if he is shooting varmints at long range, consistent placement of the eye relative to the scope is even more crucial and you can't do this well without your face being up against the stock.Clouder..

pops401

You need the 50mm for light, so yall can see me & BEE going in, when yall are going home.

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Gun control is not about guns; it's about control.

Guns & Glass

Lots mis-advertising, and mis-marketing apparently is still creating confusion, or so it seems.The human eye pupil (not the one in school)will open from 2mm in bright sun light to about 7mm in the dark. That is until we hit about 30 ish, then it will open(dialate) to about 5mmExit pupil is the diameter of the shaft of light comming out the eyepiece(occular). We have been told that anything larger than your eyes exit pupil size is a waste. That can be bullspit. Some mfrs. don't want to make larger scopes because of a limited market, and it causes all sorts of optical, and manufacturing problems. Compare two scopes- Any make, SAME model.................. 3-9X40 vs 3-9X50 Exit Pupil mm: 4.4@9X vs 5.5@9X = 20% larger................ 13.3@3X vs 16.6@3XRel.Brightness: 19.36 vs 30.25 = 36% moreIf your eye was open at 5mm the 4.4 is less than optimum, and the 5.5 is more than necessary(sometimes) When raising the rifle to your eye, and trying to find the target, the larger Exit Pupil will let you see the target faster. Better example is a 4X40 scope has a huge Exit Pupil of 10mm. If you were quickly trying to see a target(especially a moving one)you would see it first with the 4X40, then the 3-9X50, last the 3-9X40.The Exit Pupil will affect Relative Brightness. Kind of like comparing a 1/2" vs 3/4" water pipe. More water will flow thru the 3/4" pipe. So, in the above scopes the 50mm will be brighter. Lets say the above scopes were Burris Fullfields or Leupold VXII's. What would happen if the above were compared to the exact same size in the Burris Signature, or Leupold VXIII model scopes. They have better glass, finer polishing, and multi layer coated lenses, etc., etc. The better scopes would provide a much sharper image at the same power. The 50mm would be both brighter, and sharper. That's what you pay for. Tried to make chart ez to read.Will post formulas, etc if asked for.

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Happy Bullet Holes![This message has been edited by Guns & Glass (edited 01-08-2002).][This message has been edited by Guns & Glass (edited 01-08-2002).]

will270win

Alright, I'll go for that until I talk to this optics guy again. Sounds pretty convincing, maybe I mighta misunderstood something when he explained it. We'll see, I reckon.

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Eat healthy, exercise, avoid smoking........Die anyway. will270win@aol.com ~Secret Select Society Of Suave Stylish Smoking Jackets~

Curly

Well, I guess I'll see how I like the 50mm lens. I am going to get the rifle. It has Leupold VariX-III in 3.5-10 x 50. Thanks for everybody's input.