Can anyone quantify the advantage of 50mm vs 40mm objective

[lancetkenyon]

30mm tube, 50mm objective minimum. 34mm tube, 50mm objective better. 34mm tube, 56mm objective even betterer. 3mm difference in mounting height is like .13". Most rings that will clear a 50mm objective will clear a 56mm objective. More adjustment if needed, more light for those extra few minutes early and late.

 

Most importantly, light transmission on the glass itself. You can get a 40mm tube w. 56mm objective with a 75% light transmission per surface of glass in a cheap scope that is darker than a 92% light transmission in a 1" tube and 40mm objective in a high quality piece of glass. Clarity and contrast too. If you can't see it clearly in the light, you sure aren't going to see it clearly at near dark.

[Couzer]

Woah you alllllmooost lost me ^^^^^ ha ha

 

So Lance which scope

 

1" tube 50mm obj

Or

30mm tube 40mm obj

 

????, considering on the 1" you could use a moa base to achieve the the same distance, I'm no expert and I enjoy hearing your thoughts cause seems like you have knowledge

[lancetkenyon]

I would say it totally depends on the scope and glass quality. I would take a 30mm tube w. 40mm objective from any of the bigger mid to high range scope manufacturers over a 1" tube 50mm objective from BSA, Simmons or Tasco any day. Heck, I would take a 1" tube 32mm objective high quality over those too.

 

But comparable mid or high scope quality, tough call. Depends on application too. 1" is 25mm, so a 30mm tube is about 20% bigger. 50mm is 25% bigger than 40mm. So technically, you should get 5% more light transmission from a 1" tube 50mm objective over a 30mm tube 40mm objective if glass quality and light transmission of glass and internal lens count is equal between the two scopes. I think tube diameter means a lot less to light transmission than objective diameter. But it means a stiffer/stronger scope with more adjustment.

[Coach]

My uncle who is a fishing/hunting guide up in Alaska came to AZ 10 or so years back for an elk hunt. He had a .300 Win Mag with a Leupold scope that had an objective lens smaller than the eyepiece - probably 20- 24mm. One evening at the end of shooting light we had a nice bull just 75 yards away and he couldn't find it in his scope.

 

Based on that, I'm all about 40mm minimum, bigger is a plus as long as you don't have to jump through hoops to mount it.

 

Side note, I always wondered about Leupold cutting the bottom crescent out of their scopes to make them mount closer to the rifle - not even sure they are still making them but seemed like a gimmick - anyone have real world experience with these?

[218buck]

30mm tube, 50mm objective minimum. 34mm tube, 50mm objective better. 34mm tube, 56mm objective even betterer. 3mm difference in mounting height is like .13". Most rings that will clear a 50mm objective will clear a 56mm objective. More adjustment if needed, more light for those extra few minutes early and late.

 

Most importantly, light transmission on the glass itself. You can get a 40mm tube w. 56mm objective with a 75% light transmission per surface of glass in a cheap scope that is darker than a 92% light transmission in a 1" tube and 40mm objective in a high quality piece of glass. Clarity and contrast too. If you can't see it clearly in the light, you sure aren't going to see it clearly at near dark.

Your knowledge of anything shooting related is very impressive you really know your stuff I will definitely ask you when I need any information on shooting