Rail-rings question

[oilcan]

Probably a stupid question but I'll ask anyways.
Just bought a new rifle that comes with an Aluminum Picatinny rail. Does it matter if Rings are Aluminum or steel ?
Thanks

 

[nvschütze]

You will get corrosion between the aluminum rail and steel rings (if you go that route), but it will take a long time if the rifle is kept where the humidity is low. I'm no expert on metallurgy, but I believe the corrosion we sometimes see between dissimilar metals is known as electrolysis. Has something to do with electron counts in the outer valence shells of the metal's atoms. If anyone knows for sure, please correct my lack of knowledge. I took Freshman Chemistry twice in college; got a D- both times but the second taking satisfied my Science requirement. The first one, at the University of Arizona in 1977, would not transfer to Virginia Tech in 1985...

 

[dok7mm]

I have had no problems with aluminum rings, as long as they are high quality. My favorite is Seekins.

 

[sedancowboy]

I would use Aluminum rings with AL base and AL scope.

 

[YZ-80]

You will get corrosion between the aluminum rail and steel rings (if you go that route), but it will take a long time if the rifle is kept where the humidity is low. I'm no expert on metallurgy, but I believe the corrosion we sometimes see between dissimilar metals is known as electrolysis. Has something to do with electron counts in the outer valence shells of the metal's atoms. If anyone knows for sure, please correct my lack of knowledge. I took Freshman Chemistry twice in college; got a D- both times but the second taking satisfied my Science requirement. The first one, at the University of Arizona in 1977, would not transfer to Virginia Tech in 1985...

Did you sleep in a Holiday Inn Express last night? Sounds good to me!

 

[aushunter1]

You will get corrosion between the aluminum rail and steel rings (if you go that route), but it will take a long time if the rifle is kept where the humidity is low. I'm no expert on metallurgy, but I believe the corrosion we sometimes see between dissimilar metals is known as electrolysis. Has something to do with electron counts in the outer valence shells of the metal's atoms. If anyone knows for sure, please correct my lack of knowledge. I took Freshman Chemistry twice in college; got a D- both times but the second taking satisfied my Science requirement. The first one, at the University of Arizona in 1977, would not transfer to Virginia Tech in 1985...

I would say yes that reaction can occur but as both surfaces are usually coated & not in direct contact imo that would negate this effect.

It is often seen where things like boats where steel fixtures are used on an alloy hull & bare surfaces contact.

I would say the biggest issue is one material is harder than the other but as long as you adhere to proper torque settings then there shouldnt be an issue

 

[oilcan]

Thanks for the reply's so it sounds like the aluminum will out last me. I'll get a good pair.

 

[nksmfamjp]

I'll throw some more science at you....have you considered thermal expansion?

OK, so just as we learned that the dissimilar metal corrosion is covered by adding a coating, this is covered by the joint design in a quality mount.

So, in the end, it comes down to weight and strength. I prefer aluminum rings and steel base, unless I'm using a dainty looking hunting mount, then I like steel.

 

[skipglo]

You will get corrosion between the aluminum rail and steel rings (if you go that route), but it will take a long time if the rifle is kept where the humidity is low. I'm no expert on metallurgy, but I believe the corrosion we sometimes see between dissimilar metals is known as electrolysis. Has something to do with electron counts in the outer valence shells of the metal's atoms. If anyone knows for sure, please correct my lack of knowledge. I took Freshman Chemistry twice in college; got a D- both times but the second taking satisfied my Science requirement. The first one, at the University of Arizona in 1977, would not transfer to Virginia Tech in 1985...

Your answer is 100% correct....so I will give you A+

 

[Tiny Tim]

I'll throw some more science at you....have you considered thermal expansion?

Most scope tubes are aluminum and are the thinnest member of the system. Interesting question indeed. I doubt most consider this in their choice.

 

[RYEWSKY25284]

I'm with, nksmfamjp. Metal base-aluminum rings. Both rings and bases are coated. This helps negate the metallurgy effect. Also, if you epoxy your bases and/or rings this will further diminish the metallurgy effect.
I have NEVER seen any evidence of metal corrosion in these mounting systems.
my .02

 

[ntsqd]

For electrolysis to work there has to be electrical conductivity. Anodized aluminum does not conduct electricity on the surface (low EMF, not talking about HF here!), you have to break thru the anodizing and get to the bare metal for it to conduct. If the ano is cheap & thin then you can easily scratch it where it meets the base just from the install, but good rings should be much harder to scratch.

 

[cohunt]

if anodized steel to aluminum contact were an issue then all those military m-16's would be corroded by now-- they use metal pins, bolt catches, mag releases, trigger, hammer, barrel etc in anodized aluminum receivers-- I'm pretty sure that the alloy has some bearing on electrolysis too-- we arent talking about dead soft aluminum here , rings and bases are usually 6061, or 7075 -- alum on steel is fine
if you are worried about thermal expansion (which you shouldn't be either) then you should use titanium components as the thermal expansion is less on Ti than on steel or Al
weight would be the largest factor I would think-- well after quality that is

 

[Paper boy]

Probably a stupid question but I'll ask anyways.
Just bought a new rifle that comes with an Aluminum Picatinny rail. Does it matter if Rings are Aluminum or steel ?
Thanks

No question is stupid!

Consider this. When you attach 2 dissimalar or different metals you are actually creating a "battery" this can create a reaction and possibly cause corrosion where they attach. On that subject you also have an aluminum rail attached to a steel reciever. Short term, afew weeks is ok, long term could be a problem.

Most people who use aluminum rails attach them to AR10 or AR15 recievers that are aluminum so it makes no difference. If the rail is coated it may slow the effect, but better to change them both. This is very real science!