scope tubes

Only about 5mm. To state the bleeding obvious which is something that wives tend to do. :lol:


What exactly do you want to know Charlie.
 
Ha ha, I'm after an affordable long range scope but it's 25 mm tube, my other scopes are 30mm. Was wondering what difference I would see.
 
It seems often the case that 25mm tubes are used with metal fixed power scopes and 30mm with alluminium variable power scopes. Not always the case, but largely so.
It's also a fashion thing too, but those with knowledge and understanding of calculating the technical performance differences will know the correct answer as to whether 30 is better than 25mm in performance terms.

Personally I've used fixed power scopes with 25mm tubes for over 30 years and never felt disadvantaged, but I do like the view through the Swarovski Z6. ATB
 
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As JCS points out there aren't any true 25 mm scopes that I can think of they are 1" which is 25.4mm.

The main advantage of the 30mm scope over a 1" scope is supposed to be the range of scope adjustment is greater with a 30mm tube. I was also always led to believe that light transmission is better too with the larger tube in the case of variable scopes, as the mechanism needed to allow changing the magnification takes up some of the available space inside the tube.
 
As JCS points out there aren't any true 25 mm scopes that I can think of they are 1" which is 25.4mm.

I'm a joiner so my tolerances are a little bit more so an inch = 25mm, 0.5 mm is either leave the line on or cut the line off.
 
I asked a very experienced shooter/rifle builder this very question years ago, he said that the 30mm tubes are stronger than the 1" ones same thickness of metal
 
As JCS points out there aren't any true 25 mm scopes that I can think of they are 1" which is 25.4mm.

The main advantage of the 30mm scope over a 1" scope is supposed to be the range of scope adjustment is greater with a 30mm tube. I was also always led to believe that light transmission is better too with the larger tube in the case of variable scopes, as the mechanism needed to allow changing the magnification takes up some of the available space inside the tube.

Yes I understood a 30mm tube was advantageous for long range shooting because of the extra elevation and windage adjustments possible.

I would have thought the light transmission would depend rather more on the diameter of the eye piece rather than the tube diameter, but I guess it is whether the magnification adjustment takes place within the tube or eye piece, I always assumed the latter...must take one part one day!

Alan
 
The original 30 mm target and "Sniper" scopes did have extra adjustment in elevation for long range shooting but lots of manufacturers jumped on the 30mm band wagon and just putt eh usual 1" tube adjusters in but of course whacked the price up for the 30mm version and well the faddists (must have the latest thing) all dived in and stumped up for them in droves.

Of course back then finding 30mm mounts was also fun ........................................... as not many makers offered them.

Now t'is the opposite and finding decent 1" and 26mm mounts is harder than the 30mm ones or so it seems.

Although I own a few 30mm tubed scopes I honestly cannot detect any benefit from the lager tube. It's heavier of course and looks huge on some rifles. I prefer 1" or 26mm.


Oh BTW i do have a 25mm tubed scope but it's a rail mount Hensoldt 4x with alloy tube. No idea of age. it was bought for a specific project/rifle that never happened due to a greedy RFD who despite accepting a deposit on the rifle then sold it to someone who offered more than the price we agreed upon. The rifle was a Ross M10 in 280 Ross that had been drilled an tapped at some point for Redfield Junior mounts.
 
Is there much difference between 25 - 30 mm tubes?
Leon
?
Leon,
Do you mean 1" (25.4mm) vs 30mm?

There may or may not be a difference in the glass. Alot of people believe you get larger lenses, hence more light transmission. However, that is not necessarily true.

There is usually a difference in internal adjustments.

However, it is best to contact the manufacturer if you have a particular need.
 
Tube size makes no difference to light transmission. 30mm tube ( subject to manufacturers design) may offer more adjustments and may also be required to house the optic configuration. A 8x56 in a 25.4mm tube will receive and deliver the same amount of light as a 30mm tube ( excluding coatings etc).
 
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