Rifle Scopes scope main tube size.

[joemusso]

what is the importance of the main tube size. is it the bigger the better?

i am shooting 1000 yards and less with a .308 if that matters.
i just don't understand where the main tube size comes in to play.
i dont want to buy a scope because it has a big main (35mm) tube if a (30mm) will be just as good.

thank you for the info
joe

 

[i_rep]

Re: scope main tube size.

Used to be:

Larger tubes meant larger diameter holes to let light in out (transfer). Now there is optical quality glass from many manufacturers.

The main reason is larger tubes (like bigger pipe) are (1) more durable (2) larger tubes mean the adjustments/reticle is able to have more travel and this means more elevation and windage adjustment.

With a 308 you will be just fine with a quality 30mm tube.


Ask your wife, girlfriend, any chic you know. They will always tell you bigger is better. After all we think the same when it comes to them.

 

[tylerw02]

Re: scope main tube size.

Larger main tubes don't let more or less light in. That's determined by the surface area of the objective as I understand it. The larger main is for a thicker, more robust body or to provide more adjustment travel.

 

[Chris@InterstateGuns]

Re: scope main tube size.

Depends on the manufacture of the optic.

Some manufactures have glass matching the tube diameter. Basically what that does is give you more processing power. ie swarovski. Their 30mm tubes have 30mm glass.

Some manufactures do it to give you more range of adjustment. The glass will be smaller than the actual tube diameter. ie nightforce. They use 30mm tubes for rigidity however 1" glass to give the shooter greater range of adjustment.

I think consumers sometimes to forget to look at why/what application the manufacturer is trying to make an optic for.

Just in terms of glass for example different manufacturers look for different properties. One company may have resolution as the top priority where color representation may not be as important. One company may look for color fidelity.

I guess this is a long winded way of saying tube diameter can serve many different purposes and a lot of times that purpose can be manufacturer specific.

 

[joemusso]

Re: scope main tube size.

thank you guys. here is what i am looking at. Could you let me know what you think about these scopes. or any other recommendations. my main shooting is at 600-1000 yards.

IOR 6-24X56 or 9-36X56
or
nightforce 5.5-22 x 50 NXS or 8-32 x 56 NXS

thank you
joe