Steel or aluminum scope base/rail for new build?

[gotcha]

O.K., What is the difference in coefficient of expansion between 6061 & 7075 aluminum? Anyone know?

 

[Lapua40X]

O.K., What is the difference in coefficient of expansion between 6061 & 7075 aluminum? Anyone know?

Aluminum Alloy - 6061 13.0
Aluminum Alloy - 7075 13.1

 

[22BRGUY]

At one point in my life I was in the siding business and I learned that aluminum expands and contracts approximately 16 times more than steel with temperature. This was important when installing aluminum siding because it needed to be overlapped at the seams much more than steel. Also, when installing siding, it was much more important to allow for "movement" due to heat and cold with aluminum, and even much more with vinyl.

This is just a generic comment regarding the properties of steel vs aluminum expansion/contraction and maybe there are other factors involved with bases that may affect this characteristic.

Best Wishes

 

[Robert]

The expansion coefficient point is interesting, but what about the scope itself? It's certainly part of the equation. I'm not aware of anyone making scopes with steel tubes.

This is exactly what I was going to cpmment. C of E differences should not be of concern over those short lenghts and minor temperarure changes.

Considering thermal exxpansion would also led to consider thermal conductivity as the Al rail helps dissipate heat....

Now, as the scopes tubes are made of light metal too and could be prone to distortion, best I think is to use same characteristics as interface

R.G.C