Scope Mounts etc.

[CASEC]

I have a couple of questions. I see scope mounts of all types made of aluminum and mounted to steel receivers.

Do the different metallurgical properties of steel vs aluminum not affect accuracy as the steel hits up with extending firing?

[CASEC]

Anybody?

I would think that the two metals heating and expanding at different rates would impact accuracy.

[waveslayer]

I have a couple of questions. I see scope mounts of all types made of aluminum and mounted to steel receivers.

Do the different metallurgical properties of steel vs aluminum not affect accuracy as the steel hits up with extending firing?

First off, if your receiver is getting that hot then you have bigger problems then that! The scope base doesn't heat up. Unless you are shooting an A.W. automatic weapon for those that haven't shot outside CA.

So not sure what your question is really asking? What fun is it for and what are you mounting and what will it be used for? Hunting, looks, range, long range, etc..

My wife thinks I have only 3 guns

[kcstott]

4140 Steel moves .00000678" per inch per F˚
7075 aluminum moves about double that number

so if your action is 10" long and it started out at say 70˚ that day and you set it in the sun and now it sitting at 105˚ you have a 35˚ temperature shift.

so the whole receiver grew in length .0023" the area where you scope base is grew .001"

Your rings grew in width by .0004" the base if steel grew .0002" if aluminum .0004"

The diameter of the receiver changed .00032" If we are talking about a Rem 700 with a 1.350 diameter.

Even at 150˚ you only end up with .0005" per inch growth in 4140 steel and .001" in 7075 aluminum.

things need to get frigging hot before anything dramatic will happen.

now what is more likely to effect accuracy it the temp of the ammo and the burn rate of your powder changing, not to mention your barrel shifting due to internal stress.

That said things can go wrong with extreme temps. My uncle flew out here and upon his arrival we found a Talley tactical ring had snapped at the thinest portion of the ring but it had also sat at 35,000 feet with sub zero temp for six hours... so something happened.

[CASEC]

Thank you as those were helpful. If I understand things won't move enough to matter with normal firing.