30mm tubed scopes for hunters?

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Does anyone mount 30mm scopes on hunting rifles.

Do you choose it for the tube size or the other specifications like "model" quality/Brand/adjustment? Example my mate likes the Swarovski z6 series.

Do you feel there is any specific advantage?

I know it can offer more adjustment but is there any advantage to the hunter?
 
Does anyone mount 30mm scopes on hunting rifles.

Do you choose it for the tube size or the other specifications like "model" quality/Brand/adjustment? Example my mate likes the Swarovski z6 series.

Do you feel there is any specific advantage?

I know it can offer more adjustment but is there any advantage to the hunter?
This is a good thread
 
30 mm scopes on rifles I have taken to Africa. (404J and 375 HH) I inch on my rifles I hunt local (deer) with. Its what you can afford and what makes you happy. If I could afford it I would probably have 30mm German on everything.
 
Thanks for the kind words Wishfulthinker580, here is the post, for everyone's convenience :)

Why a 30 mm tube on scopes with objective bells...

The 30 mm tube choice has nothing to do with light transmission. The only advantage a 30 mm tube has over a 1" tube on a scope with an objective bell, is that it allows more room internally for a wider range of adjustment of the scope erector, i.e. the mechanism that holds the reticle:
  • The reason why European scopes standardized at 30 mm instead of 25 mm is that in days when the tolerances on the mounting of scope bases were much looser than today, a 30 mm scope generally had enough internal adjustment to avoid having to shim the bases and/or the rings. 25 mm scopes often needed external adjustment in addition to internal adjustment. A definite weakness...
  • The reason why virtually all modern military scopes have 30 mm tubes is similar, but applied to a different purpose. More internal adjustment allows more elevation clicks to shoot farther.
  • The reason why some military scopes are now available with 34 mm tubes is more of the same: more internal elevation clicks for latest longer range loads (e.g. Lapua, etc.).
Why a 30 mm tube on scopes without objective bells...

First we need to explain a little more the exit pupil concept. Yes, human pupil vary in diameter from 2 mm to 7 mm, but the application of this fact has nothing to do with the tube diameter, because indeed whether the tube be 25 mm, 1" (25.4 mm), 30 mm or 34 mm is irrelevant to a 7 mm light beam. @Bert the Turtle is correct!

The application of the basic rule that a 7 mm light beam must desirably reach the pupil at full dilatation in low light condition applies to the diameter of the objective. The basic rule is that magnification x light beam diameter determines the diameter of the objective. This is the reason why most European x6 scopes have a 42 mm objective (6x 7mm = 42 mm), most European x8 scopes have a 56 mm objective (8x 7mm = 56 mm), etc.

This is the reason why a straight 1" tube DG scope with 20 mm objective on a .375 H&H rifle that may see yeoman service on a 1 rifle safari involving early or late shooting, is not ideal. Regardless of glass quality, a 1.5-4x20 straight tube 1" scope only produces a 5 mm light beam at 4x (20 / 4 = 5). This typically means 5 to 10 less minutes of shooting light at dawn or dusk, and that may make all the difference in the world, where legal...

Everything else (such as glass and coatings quality) being equal, you will factually see a Leopard at dusk, or a Kudu at dawn, better with a 42 mm objective than with a 20 mm objective because a 42 mm objective will collect a 7 mm light beam at 6x and a 20 mm objective will only collect a 5 mm beam at 4x. The best glass in the world, from whichever manufacturer, will not make up for this. Period.

A straight 30 mm tube DG scope with 24 mm objective is a step in the right direction. At 4x a 24 mm objective gives you a 6 mm light beam. This is not as good as 7 mm, but this is appreciably better that 5 mm.

I personally play the game on both ends: I use a 30 mm straight tube because of its 24 mm objective, and I rarely use it at more than 3.5x because it produces a 7 mm light bean at that magnification, and anyway I do not shoot far in general when I use a DG rifle... and anyway I am incapable of seeing a difference between 3.5x and 4x... and anyway any variable optic from any manufacturer will typically not have the best image quality at max power...

Please note that all these considerations disappear when using the scope in full day light when a younger shooter pupil is shrinking to 2 mm and an older shooter pupil is shrinking to 3 mm. This is why a modern straight tube scope with a lot of magnification still makes some level of sense. It would be a gross misuse of a Z8i 1-8x24 to try to use it at 8x at dawn or dusk because its 3 mm beam would not even carry half the light the shooter could use and would need, but at high noon this 3 mm beam would work just fine. Although why one would want 8x on a DG rifle scope escapes me...

In summary:
  1. A 30 mm tube provides a wider internal adjustment range, which may solve a less than perfectly aligned scope mount issue, and which allows more internal elevation clicks, useful for long range shooting;
  2. On straight tube scopes a 30 mm tube provides a larger objective diameter over a 1" tube (typically 24 mm over 20 mm), which increases the diameter of light beam reaching the shooter's eye at any magnification considered.
 
I guess what I'm asking is what advantage are people getting from 30mm tubes.

As @SRvet above says they would not consider 25mm tube scopes.

I have an older 30mm tube Swarovski that I will be mounting on a .308 but wondering why people favour them
 
I guess what I'm asking is what advantage are people getting from 30mm tubes.

As @SRvet above says they would not consider 25mm tube scopes.

I have an older 30mm tube Swarovski that I will be mounting on a .308 but wondering why people favour them

Per the above...

In summary:
  1. A 30 mm tube provides a wider internal adjustment range, which may solve a less than perfectly aligned scope mount issue, and which allows more internal elevation clicks, useful for long range shooting;
  2. On straight tube scopes a 30 mm tube provides a larger objective diameter over a 1" tube (typically 24 mm over 20 mm), which increases the diameter of light beam reaching the shooter's eye at any magnification considered.
 
It seems to me that the luminosity of the 30mm tubed scopes is better. Certainly something is also due to the quality of the optics, depending on the brand of the scope.

In Africa, where hunting is mainly done during the day and with high luminosity, it may not be so relevant, different if you also hunt at night, as in our regions.
 
Per the above...

In summary:
  1. A 30 mm tube provides a wider internal adjustment range, which may solve a less than perfectly aligned scope mount issue, and which allows more internal elevation clicks, useful for long range shooting;
  2. On straight tube scopes a 30 mm tube provides a larger objective diameter over a 1" tube (typically 24 mm over 20 mm), which increases the diameter of light beam reaching the shooter's eye at any magnification considered.

Yes, I'm aware of some of that and that is why I'm just digging further to find what steering people's preference s
 
I like the increase of objective diameter of most straight tubed 30mm scopes, compared to 1" tubes. The straight tubes were my first 30mm's. I become accustomed to "the look" of 30mm tubes. Most of my scopes now are 30mm tubes.

Not specific to the tube size, but at one time the scopes with 30mm tubes also generally offered wider field of views, than 1" tubes. This was also a big purchase factor for me.
 
The mount is certainly not the first reason for choosing an scope. There are a lot of very different mounts nowadays for everything, including 30mm und even 34mm tubes.

I think that the price of the scopes also plays a role. The top European scopes are currently more expensive than the rifles.
 
It seems to me that the luminosity of the 30mm tubed scopes is better. Certainly something is also due to the quality of the optics, depending on the brand of the scope.

In Africa, where hunting is mainly done during the day and with high luminosity, it may not be so relevant, different if you also hunt at night, as in our regions.
Mostly the case, except when hunting Buffalo in the thick jess. A black animal in shade requires all the luminosity you can get!
 
It seems like most of the higher end optics with features I prefer (illuminated reticle/red dot) use 30mm tubes. Thinking about it, I am about 50/50 with 1" tubes and 30mm tubes. Meopta and Trijicon are 2 of the few that still make 1" tubes scopes with illuminated dot/reticle. I still love a Swarovski Z3 or Leupold VX3 and have them on several rifles. I actually prefer the looks of the 1" tube scopes.

Safe shooting
 
It seems like most of the higher end optics with features I prefer (illuminated reticle/red dot) use 30mm tubes. Thinking about it, I am about 50/50 with 1" tubes and 30mm tubes. Meopta and Trijicon are 2 of the few that still make 1" tubes scopes with illuminated dot/reticle. I still love a Swarovski Z3 or Leupold VX3 and have them on several rifles. I actually prefer the looks of the 1" tube scopes.

Safe shooting

Like you, I prefer the appearance of 1” scopes but have many 30mm scopes due to the quality of glass and illumination I am looking for. I wish Swarovski would make a Z6 quality scope with illumination in a 1” tube.
 
I put 30 mm scopes on my Sako 85s. They wear the larger scopes really well and the glass is excellent making a big difference. Most of my rifles still have 1” 3-9 Leupolds and I see no reason to change. I wish they made higher end optics in 1” tubes. There are rifles I’d like the better glass but not the added weight. I put a 30 mm scope on my R8 and have to say I hate it with that rifle. It’s just way too large for that particular rifle for me. I haven’t invested the time into that particular rifle I should, but it will be getting 1” scopes, maybe Swarovski Z3s.
 

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