Yes, Jon is right. I had the 40mm ordered but then changed it to get the 50mm. While I have a few scopes that are 40mm, most are 50mm. Some people say that you won't notice a difference, but I can - especially when it gets very dark (but still legal shooting time.)
You see, it can sometimes be almost pitch dark outside and still legal. How? Well, you could be in heavy timber and/or the sky could be very, very overcast with no moon. Believe me, I like my 50mms better.
But light transmission is not the only thing. The bigger the exit pupil, the more leeway your eye has to be aligned.
The biggest reason I got the 50mm (which is a combination of the two) is because as you get higher magnification, the exit pupils get smaller. Well, it's not that big of a deal when you are talking about 7x,8x, or 9x. But when you start talking about 12x,13x,14x,15x, 16x or more, then you have to understand that the exit pupil of a 40mm scope set at 16x is going to be quite small, and not very helpful at low light conditions.
As such, my personal opinion and experience is, if you are going to get a scope 10x or above, then I like to get scopes with 50mm objectives. Again, some people will tell you differently, but I'm sticking to my guns (no pun intended).
As for mounting a scope low, to me it's also about personal preference as well. Yes, a lower mounted scope is better tragectory speaking, but I have never had a problem shooting 50mm objectives. Yes, it does make the rifle handle a little bit different, but to me it's not noticeable.
Jon was very helpful in upgrading my order. Let me tell you, I'm glad I did. The Elite 4200 4x-16x-50mm is one of the finest scopes out there regardless of price. To me, it's much better than the Leupold Vari-X III, and I own 2 Vari-X IIIs in 4.5x-14x-50mm ILLUMINATED.
Get the Elite 4200 4x-16x-50mm and you will thank me.
Zachary
