1" VS. 30mm

[PA1936MN]

So I am seeing a lot of people saying they want a 30mm tube size over 1" tube size.

1" obviously ='s 1"

30 mm = 1.18110 "

So with that said, to me it doesn't seem that it is that much bigger to warrant spending more for a 30mm over a 1" model. I am also finding more 1" models rather then 30mm models.

- What are the big differences?
- What are the advantages of each?
- What are the disadvantages of each?

[PhilB]

So I am seeing a lot of people saying they want a 30mm tube size over 1" tube size.

1" obviously ='s 1"

30 mm = 1.18110 "

So with that said, to me it doesn't seem that it is that much bigger to warrant spending more for a 30mm over a 1" model. I am also finding more 1" models rather then 30mm models.

- What are the big differences?
- What are the advantages of each?
- What are the disadvantages of each?

I am certainly no expert on scopes, but from a general optics standpoint, 30 mm has a big advantage. The optic will be "brighter", meaning it will transmit more light. This will be obvious the first time you use it in low light conditions. (The same as 8X42 binoculars are brighter than 8X30 binoculars.)

In other respects, the scope may be a bit heavier and will probably cost more because of the larger lenses.

--Phil

[bigandy1966]

The objective lense is what gathers the light. 50 mm gathers more light than a 40 mm (think about an eye retina). I just stick to 1" stuff to keep it simple.

[PA1936MN]

The objective lense is what gathers the light. 50 mm gathers more light than a 40 mm (think about an eye retina). I just stick to 1" stuff to keep it simple.

I realize the AO gathers the light. And that 50mm is bigger then 40mm which in general would gather more light. But that also depends on the optics, coatings, etc... Because a 40mm with a better all around package can gather more light then a 50mm with lesser quality parts.

I just keep seeing 30mm and 1" thrown around and wondered which was better and why. Because IMO 30mm isn't that much bigger then 1". In reality it is bigger but not that much bigger.

[bigandy1966]

maybe its got something to do with European standards, you know how they hate the English system of measure

[PA1936MN]

maybe its got something to do with European standards, you know how they hate the English system of measure

Maybe. I mean yes it is bigger in size, but not by much.

[spblademaker]

The only true benefit I can see with a 30mm is that there is more surface area in which to make contact with the rings. More contact = more grip. A 30mm scope body, being held with 1inch wide rings would have 7.42 inches of contact as apposed to 6.28inches of contact with a 1inch scope body being held by the same width rings. Please correct me if I'm wrong, but it's early and my brain is now bleeding!

[PA1936MN]

The only true benefit I can see with a 30mm is that there is more surface area in which to make contact with the rings. More contact = more grip. A 30mm scope body, being held with 1inch wide rings would have 7.42 inches of contact as apposed to 6.28inches of contact with a 1inch scope body being held by the same width rings. Please correct me if I'm wrong, but it's early and my brain is now bleeding!

Wouldn't you just purchase 30mm rings and not 1" rings if your using a 30mm tube scope?

[spblademaker]

Wouldn't you just purchase 30mm rings and not 1" rings if your using a 30mm tube scope?

"1inch WIDE rings", not 1inch diameter rings! You cant figure surface area without the WIDTH of the rings. Since the formula uses the radius of the circle (.5 for 1inch, or .59 for 30mm) it is already evident that you are using the correct ring diameter. You keep the WIDTH the same so as to keep the experiment unchanged in comparing the surface area calculations. "But thanks for playing! Tell him what his parting gifts are Johnny!"

[LisaA]

With 30mm scope, you have a greater range of adjustment in elevation and windage, which is better for long range shooting. Also, it is easier to align your eye behind the scope.