Is a 50mm objective that much better?

J

jwaldrop3

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Is a 50mm objective that much better than a 40mm on a 4-16 riflescope? Do you need high rings to mount a Nikon Monarch w/50mm objective to a Remington 700 SPS Tactical? Medium height rings for a 40mm objective Nikon Monarch?
 
Define "better". I've seen good quality 40mm objectives that are clearer and gather more light than some other 50mm objectives. Better is a relative term and needs to be examined in light of the particular scope you are considering.

As to rings, yes 50mm objectives normally do require tall or even extra tall rings.
 
If you are referring to the common notion that bigger is better and has some sort of advantage....well no, not really. The common thought is that the larger the objective the more light it will gather and in turn transmit. This is true if the exact same scope were compared side by side, but with say....the 40mm objective. Let's say you have a Burris 3-9x40mm Signature series and the same scope in 3-9x50mm. Technically there will be more light gathered and in turn transmitted to your eye. The trade off is cost and higher rings. In many cases, the most advantage you will ever realize is possibly 5-7 minutes more of clear vision in low/failing light. A larger objective will also give you a wider field of view, which will give you an advantage when trying to pick up your target when the power is turned up. The scope makers will give you field of view charts so you can compare. "Tactical" rifles almost never have large objectives because they require the higher rings and then cause you to stretch your neck and not have a good, natural plane of sight or natural shooting position and....well they just aren't necessary. Remember, no matter how big the objective is, the light and image is still being squeezed into a 1" tube. Unless you go with a 30mm tube which is where you will notice a difference when comparing 1" to 30mm. Top quality glass is much better than large objectives.
 
More light transmission

Maintaining factors such as lens quality, manufacturer, etc equal but increasing objective diameter you will get a greater amount of light transmission through a scope. A 50mm objective is 1.25 times the diameter of a 40mm objective but is 1.6 times greater in area. This results in more light transmission with greater clarity and better vision in low light.
 
In theory yes, in practice for most users, no. Once you get into the high end scopes with 30mm tubes the 50mm objectives have a slight advantage. The problem with most low to medium quality scopes is that the scopes themselves are not good enough to take advantage of the theoretical advantages. A good quality scope with a 40mm or even smaller objective will work better than a mediocre 50mm objective. And will probably cost less.
 
Made a slight mistake

My post stated that greater light "transmission" is a result of increased objective lens diameter. I should have mentioned that light "gathering" is the factor that increases with increasing objective lens diameter. Light transmission from the objective lens to the eyepiece is another matter.

Sorry for the mistake.
 
50mm vs smaller vs quality coating/transmission

All things equal, a 50mm with the same coating, quality of glass, and close to barrel mounting WILL be better than a 40mm of the same quality.
It will have better field of view, light transmission (from gathering more through it's superior area), and for lack of a better term "give you more".
All things equal.
I had a Nikon Monarch 42mm 6 to 18 that you had to be exactly behind it to see through it. In the field thats a second of adjustment you dont have.

I'll take a bigger objective, or equal quality (I have a Zeiss Conquest on my 700 Sendero and I LOVE it) over an equal smaller objective all day.

I veiw it as a question of my quality of experience at my hobby. Which I have one of.
I dont get to shoot enough to waste time with marginal equipment, or anything less than what I need FOR ME to enjoy what I do.
A good day in the field or at the range.....What is THAT worth to you?
 
The question is what are you using the rifle for. If it's low light varmint shooting then all things being equal it will give you a bit more light and bit better field of view. If you're shooting targets in broad daylight then I don't see any advantage. For stalking style hunting or plinking I don't want that much magnification or weight.
 
weight issues

He is right. You WILL feel that weight difference if you havent used one before.
I had a model 788 with a 3x9 on it that I could carry with one hand all day, I could never consider that with my heavy barrel varmint rifle.
But I can shoot much farther and more accurately.
Its all about what you pay, for what you get.
 
Light gathering capability goes by surface area, so a 50 mm has more than double the light gathering capability of a 40. It also means you can dial in more magnification and still get the optimal exit pupil size (7 mm) for dusk/dawn performance (40 6x, 50 7x, 56 8x). It also means that at 4x anything more than 30 mm is wasted, the gathered light does not enter your eye.
So, if you're usually moving through brush with the scope dialed to 3 for the quick shot, definitely stay light and go with the 40 mm and 1" tube. If you end up at 9 shooting from a stand at long distances, a 50 with a 30 mm tube might be appropriate.
 
would just look through both and compare them and pick wich ever you preffer, my personal opinion is you dont gain as much on larger objectives in high quality scopes that have great light transmission to begin with but I usually leave mine on around 5 power most of the time hunting anyway. others gave you good advice depends on what type of hunting your doing but I really recomend looking through them before you buy.
 
You can get tricked with a cheap scope. If the scope is not correctly engineered the 50 mm objective will not gain anything. A lot of these cheap scopes are poorly engineered and you have to compare them side by side with a comparable scope of high quality to tell the difference.
 
Not quite 2X

A 40mm diameter objective lens is 1256 sq mm in area. The 50 mm is 1962 sq mm in area. Area increase from 40 mm to 50 mm is 1.56 times not quite twice. A 56.6 mm diameter lens is twice the area of a 40 mm lens.
 
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Wonder if there is any high quality scopes using 30mm tubes and smaller 40-42mm objectives? As mentioned above- tall rings= pain in the neck
But it is nice to have the extra elevation range and field of view in a 30mm tube. Leupold makes that V notched objective that may be one answer to the tall ring problem, I like the idea but not sure if Butler Creek yet makes a scope cover for them-surely they will.:eek:
 
I have all Leupold scopes, and not saying thats the one to buy because there are a few real good ones out there. Most of mine are the 40mm, and lots of times I will look thru a friends cheaper scope with a 50mm on it, and the 40mm most the time will gather more light, and is sharper. I guess the quality plays a big part in it. I dont think you need to spend a arm and a leg, but try to get a pretty decent one. The more you can look thru or shoot the better. Also I get the correct hight mounts, and the 40mm most of the time will give you a better glue to the stock. Good luck!
 
Agree with James.... I have a bushnell banner 50mm and a bushnell elite 40mm. and the 40 is for sure much clearer than the 50.... I believe that quality plays more part in it than the larger objective.
 
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