40 mm vs. 50 mm scope.

[nwihunter]

I posted this thread in the firearms section instead of the optics figuring it might get more views. I admit I’m not very knowledgeable about rifles and scopes but am wondering what the advantages or disadvantages are to having a 50mm vs a 40 mm lens scope? I currently have a Leupold vx-3 HD 4.5 -14 x 40 on my rifle and is definitely the only quality scope that I’ve ever owned. I recently sighted in a rifle for a friend of mine that had a lower end Leupold scope but with a 50 mm lens and found that I liked it more than the 40mm that’s on my rifle so it’s got me thinking about getting a new scope. Any down side to the larger lens?

 

[Nick87]

Being higher of the center of your bore. Probably not enough to worry about though.

 

[Salmonchaser]

If you have younger eyes you may be able to take advantage of increased light transmission however if you are pushing middle age your eyes are becoming more limited in how much light they can receive so the light transmission advantage is lost. I’m not an eye doc but my eye doc is a big time shooter, competes all over the country and says the light transmission sales pitch is a gimmick. Yes more comes through but older eyes just can’t take advantage.
Im interested in what aspect of your friends scope you liked, was it a 4.5x14 also?

 

[perma]

The larger lens is supposed to let more light in. I’ve shot both a 50mm and 44mm, there’s a difference but marginal. You’ll likely not notice the difference when your adrenaline is running when the game is on the crosshairs.

That being said, the added weight does help with the recoil. Makes my 7 mag feel like a 223. Pretty nice in that respect.

 

[huntnfisher]

I have 2 Leupold VX-5HD's Firedot Duplex 3-15x...1 in 44mm, 1 in 56mm. I have compared them side by side in low light. There is a noticeable difference although it's small. Then again, I am 68 years old.

 

[grizzly63]

The bigger the lens, the higher your point of view is meaning its harder to get that good cheek weld that aids in accuracy. They do let in more light.

 

[RemingtonRules]

Never felt the need for a 50. Heavy, bulky, and sits too high for my taste.

 

[TheTone]

I’d rather have a higher end 44mm than a lower end 50

 

[Bowhuntrben]

One thing to keep in mind is that higher end scopes tend to have better coatings on them. I had a 50mm scope on my main rifle that I took off and upgraded to a VX-5HD. My 50mm failed me with glare at a critical moment that I don't believe my new scope would've had an issue with. The 50mm wasn't a cheap scope either, but I believe the VX-5HD has better coatings. I would be more worried about having better coatings than any additional light you may get by having the larger objective. My experience is that either objective will allow you to see beyond legal shooting light. I'm no expert though.

 

[Boarmaster]

I have owned a few 50s. I traded or sold them. Just seemed too big to me as a hunter who always used good quality 42s,40sand 36s. I never had any issues with enough light , even in the woods with my scopes in legal shooting hrs. That said a 50 isnt exactly a hubble telescope.

 

[std7mag]

I have 40, 42, 44, 56, 60.

The 60 is only used for matches. But not because of the objective size. But rather the magnification. 10-50X60.
And the 60mm objective isn't really any heavier than some of the smaller objective scopes.

The 40,42 are "darker" than the 56 & 60.

While the 60 is brighter, it doesn't necessarily mean that it is better optically than some of my other scopes.

Essentially what I'm trying to say is good glass is good glass.
And you can readily tell the difference between good, and not so good glass.

There are other things that are more important than just the objective size.

How does it track?
How smoothly do the controls work?
Is the magnification range suitable for your usage?
Does it have the reticle that you want?

As far as flaring out is concerned, I've found that to be more of a coating issue. And you'll see that it happens with one manufacturer more than other manufacturers.
Not to name names, Vor***.

 

[Speeddmn]

As mentioned a few times. The larger the bell, housing the more light can come in. Think dusk, last few minutes of legal shooting light. You have a older 1” tube with a 40mm objective. With fine plex cross hairs, there may not be enough light to make a quality shot. But stepping up to a 30mm tube and 50mm objective with illuminating retical (where legal) would allow you to make that shot ethically.

Scopes, rifles, bipods and such are all tools for the trade. This is why we have thousands to choose from. Not one item works for everyone, well maybe the now super famous “butt out”!

 

[nwihunter]

If you have younger eyes you may be able to take advantage of increased light transmission however if you are pushing middle age your eyes are becoming more limited in how much light they can receive so the light transmission advantage is lost. I’m not an eye doc but my eye doc is a big time shooter, competes all over the country and says the light transmission sales pitch is a gimmick. Yes more comes through but older eyes just can’t take advantage.
Im interested in what aspect of your friends scope you liked, was it a 4.5x14 also?

It was a 3 x 9. What I liked about it the most was it just seemed like it was easier to pick up the target. I’m assuming with the bigger lens is it had a bigger field of view.

 

[EastTNHunter]

But stepping up to a 30mm tube and 50mm objective with illuminating retical (where legal) would allow you to make that shot ethically.

Quick correction, the way that it’s been explained to me by people much smarter than me… 30mm tube does nothing for light transmission, only allows for more elevation and windage travel

 

[Wind Gypsy]

If all else is the same (which it rarely is) a larger objective lens is going offer a brighter image of higher quality and be more forgiving of eye placement behind the scope.

I think mounting a scope low for cheek weld is highly overrated. I’d have no concerns from a size perspective having a 50mm obj scope but find all my hunting scopes to be 42-44mm objectives just because that seems to be what is available in the functional and weight range I want.

 

[huntnfisher]

If all else is the same (which it rarely is) a larger objective lens is going offer a brighter image of higher quality and be more forgiving of eye placement behind the scope.

I think mounting a scope low for cheek weld is highly overrated. I’d have no concerns from a size perspective having a 50mm obj scope but find all my hunting scopes to be 42-44mm objectives just because that seems to be what is available in the functional and weight range I want.

Same here, I have never been obsessed with having a super low cheek weld, and I shoot just fine.

 

[noharleyyet]

If all else is the same (which it rarely is) a larger objective lens is going offer a brighter image of higher quality and be more forgiving of eye placement behind the scope.

I think mounting a scope low for cheek weld is highly overrated. I’d have no concerns from a size perspective having a 50mm obj scope but find all my hunting scopes to be 42-44mm objectives just because that seems to be what is available in the functional and weight range I want.

Conversely, I do not want cheek disconnect.