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Riflescope Objective Lens Sizes

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gil1

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Please excuse me if this topic has been discussed. I did a search and couldn't find it.

A friend was recommending a riflescope, and he has 3 deer scopes that are 3x9x50. I'm in the market for a new scope but had planned on buying one with a 40mm objective lens. He said he loves the ability to get another 10 minutes of light out of the day. I would love the bonus light and was set to buy a 50mm.

I was doing some research on opticsplanet.net and found this recommended reading by the dealer on how to choose a scope. Below is the part that mentioned the negative aspects to a bigger objective lens. I really don't know what to do or who to trust. I would greatly appreciate some suggestions. Thanks in advance.

How to choose a scope link

Here's the important quote from the article...

"Let�s talk about objective lens sizes. 40 to 44mm is pretty standard on a medium variable rifle scope. It�s trendy these days to have large objective lenses of 50, 56, or even 75mm in some cases. In most cases, these are unwarranted, and the largest ones are laughable. Large objective lenses will only transmit more useable light than smaller ones if they are set at their highest power in the dimmest conditions. The detriment is comfort and ease of eye alignment. With a properly mounted scope, you should be able to close your eyes, shoulder your gun with a proper, repeatable stock weld (a stock weld is the firm but comfortable and repeatable position of your face on the gun stock), open your eyes, and look directly through the center of your scope every time. Large objective lenses prevent this from happening because of the ring height required to keep such a large lens off your gun barrel. Some scopes require such high mounting that only your chin touches the stock. These scopes are also heavier, clumsier, unwieldy, unbalanced to carry, slower and less comfortable to shoot. Some of these scopes weigh up to an unbelievable 3.5 pounds!"
 
LENS QUALITY wins out every time,,I have a couple of 40 mm Ziess Conquests that are brighter at dark than the 50 mm on the couple of Vari-x III`s I have.

I have sit out here behind the house at dark and can read the 100 yard target a good 4-5 minutes longer with the Ziess than the Leupold,,it aint all about size.
 
Thanks, Mr. Big. If you had to choose between the 40mm lens and 50mm lens on the exact same scope, though, which would you choose? I guess that's my question.
 
the answer is, it depends :D a 3x9x40 has an exit pupil (obj size / Magnification) from 13 down to 4.45. A 3x9x50 is 16.67 to 5.56. IIRC the max the human eye can handle is 7 in pure darkness.

A 50 will be mounted higher, so how does that impact the cheeck weld and your shooting, only you can know that.

What scope are you looking at and what gun will it be mounted on?

Pmc�
 
gil,the conversation reminds me of when the late Jim Varney was a regular on Buckmasters with the HUGE(fake) black scope mounted on his rifle. A joke, of course, in that situation, but it is kinda the point your article makes, there is a size limit of practicality. I've owned larger objective lens, but have never seen much difference in them and 40mm under hunting conditions. As PMC points out, the amount of light entering your eye from the exit pupil is the key, not the amount of light coming into the Objective lens. IMO 40mm's are good as gold during legal shooting hours. However, its fun trying tweek all of your equipment into giving yourself every possible edge. LOL
 
I'm pretty much at a loss. It's for my 30.06 Remington 700. I want a decent scope that's not out of my price range ($200-$300) and have no experience in the matter.

My old scopes are really cheap, and I want an upgrade. I had been hunting all deep woods (max 75 yard shots), but now I've got a lease where it's more open, and I'd like to expand my range and at least practice out to 150-200 yards.

From reading through the posts on here, I was looking at Nikon Prostaff, Simmons ATEC, Burris Fullfield 11, Bushnell 3200 Elite, Swift Premier, etc. My buddy had recommended the Nikon Buckmaster with the 50mm objective lens.

I've got to pull the trigger (pun intended) soon so I can get some practice in before rifle season so I can see at what range I'm comfortable shooting. Any thoughts on my particular situation? Thanks again in advance.
 
4onaside said:
gil,the conversation reminds me of when the late Jim Varney was a regular on Buckmasters with the HUGE(fake) black scope mounted on his rifle. A joke, of course, in that situation, but it is kinda the point your article makes, there is a size limit of practicality. I've owned larger objective lens, but have never seen much difference in them and 40mm under hunting conditions. As PMC points out, the amount of light entering your eye from the exit pupil is the key, not the amount of light coming into the Objective lens. IMO 40mm's are good as gold during legal shooting hours. However, its fun trying tweek all of your equipment into giving yourself every possible edge. LOL
Click to expand...

I can see Ernest now. LOL
That's what concerns me. I've been hunting a long time but have never really gotten too cutesy with my setups. I don't have enough knowledge to take risks on my equipment. Heck, I just want something I can work with and don't want to spend a bunch of money on a mistake.
Ya know what I mean, Vern?
 
gil1 said:
4onaside said:
gil,the conversation reminds me of when the late Jim Varney was a regular on Buckmasters with the HUGE(fake) black scope mounted on his rifle. A joke, of course, in that situation, but it is kinda the point your article makes, there is a size limit of practicality. I've owned larger objective lens, but have never seen much difference in them and 40mm under hunting conditions. As PMC points out, the amount of light entering your eye from the exit pupil is the key, not the amount of light coming into the Objective lens. IMO 40mm's are good as gold during legal shooting hours. However, its fun trying tweek all of your equipment into giving yourself every possible edge. LOL
Click to expand...

I can see Ernest now. LOL
That's what concerns me. I've been hunting a long time but have never really gotten too cutesy with my setups. I don't have enough knowledge to take risks on my equipment. Heck, I just want something I can work with and don't want to spend a bunch of money on a mistake.
Ya know what I mean, Vern?
Click to expand...
Yeah, I do Ernest!
I'm probably out of line even talking to you on the serious side of scopes, because for many years I have bought the cheapest Bushnell scopes available, usually Sportviews,and even Tascos on occasion, because of adequate quality and few dollars, and have been just as happy as a pig in mud with them. I just never have found any brighter optics than Bushnell(of course, I haven't looked too hard when the dollars go up!). That's what works for me, and when someone starts talking two or three bills for a scope,they have lost me in the shuffle. Incidentally, these el cheapo scopes work like a champ on the high plains or in alpine meadows also for 225 to 300 yard shots. But hey, what do I know! Good luck in finding what works for you. After all, that's the bottom line.
 
I think the best "cheap" scope is a Burris FFII. I`d throw a Weaver Grand Slam in there but it is much more money.

I`d throw a down payment and do a short lay-a-way for a Zeiss Conquest 3-9x40 if it were me.

We are talking serious business here now.
 
Zeiss Conquest

All of my rifles wear Zeiss optics. I made a mistake a couple years back and looked through one. :) The only other scopes that even comes close IMO are Swarovski and Meopta. For the money, the Conquest is hard to beat. This guy elkhunter777 sells alot of scopes with no reserve and the Conquest normally sells for $335-$370. I've bought numerous scopes from this person and have never had a problem.

Have you tried shooting at longer ranges with your current setup? If it's not broken.... you know the rest.
 
As PMC previously stated, its all about the exit pupil.

A 40mm can be used on 5.5x right at dusk and still be able to transmit the maximum amount of light the human eye can use.

A 50mm can be used on 7x right at dusk and still transmit max light usable by the human eye.

In my opinion, not a lot of difference, but there is a very small, sometimes noticable difference.

My opinion for very low light...

Get yourself a pair of very, very high quality binoculars (ie zeiss 8x56's or the like... doesn't really matter, as long as the exit pupil on the binocs is 7mm), to use to spot and judge the game. Then it just don't mean squat whether there's a 40mm or 50mm objective on your scope. (And it won't mean squat if you buy a cheap scope, either, just as long as it tracks true and holds zero)

BTW, I second TiminTN's opinion of the Burris Fullfield II... you can pick these up used but in like new condition for $135 or so shipped.
 
I'll tell you what, if I were gil about now, my head would be spinning! Gil, there is probably not a bad bit of info in the whole thread. It's just that everyone likes their own idea of what is good. I suppose a good approach if you are an analytical type guy, is to make a list including each recommended scope, compare the specs and compare the price of each. Then close your eyes and put your finger on the list, and bingo, that's the scope that you buy. Seriously though, the list, specs and costs would probably help you make a decision that you can live with. Good Luck!!!
 
Good advice above.


You can get into the same problem with 40 + OBJ, as that article mentioned with 50mm OBJ.Usally isn't a problem but on rare occasions have had to mount 42-44mm OBJ in High Rings.This depends on the scope length,obj bell shape and the barrel contour.Just mentioning that,it isn't a big issiue.

Personally I perfer OBJ between 36-44mm and perfer not to go above 44 so that I can mount them in Low - Med/ rings in most cases.The only 50mm I would even consider is the Leupold VX-L.

"From reading through the posts on here, I was looking at Nikon Prostaff, Simmons ATEC, Burris Fullfield 11, Bushnell 3200 Elite, Swift Premier, etc. My buddy had recommended the Nikon Buckmaster with the 50mm objective lens."

My advice look at all of them "Outside" if possible and go from there.

BTW-I have the Burris Fullfield 2 with Ballistic Plex,Nice scopes they are.However the Simmons "Master Series" line starting with the Pro Sport is brighter than it and a couple Bushnells I've looked through.

Good luck with whichever one your eyes tell you to go with.
 
I have a 3.5-10 x40 and x50 both made the same year Vari-x III`s,,the 50mm on a 300 Ultra and the 40mm on a 270WSM,,the 50mm is a little brighter right at dark,but your done past legal shooting time before you can tell a difference,I take it on morning hunts when shots can reach 500 yards at daybreak,the 40mm on the WSM is a good scope as the 50mm and is actually clearer to me edge to edge than the 50mm,and unless your going to be shooting before or after legal times I would get the 40mm,,but I would get the Ziess,,in the woods in the shadows trying to poke a bullet through some brush at 150 yards you can see stuff with it you cant with the Leupold

3-9x40 Conquest,,best 400$ huntin investment you will ever make.
the one rifle I carry the most is a Model 7SS 308 with the Conquest zeroed at 250 with 150 Hornady bullets,,I killed 2 does with 2 shots last year with it at 415 yards.

and no deer scope should have an AO lens,,
 
I cant stand shooting a rifle that I have to lift my face off of the comb of the stock to see through the scope. That eliminates the 50mm objectives for me. The tradoff for the extra minutes at dark(if there really is that much of a difference, which I doubt) doesnt matter as much to me as a natural pointing rifle with a scope mounted as close to the axis of the bore as possible.
 
Man, really great stuff, guys. I really appreciate your opinions. I think I'll go with the 40mm objective lens, but it looks like I've still got some shopping to do on which scope. So many differing opinions!
 

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