Subscribing.. in my mind it should work fine but am curious to see how quick it would wear out over a steel barrel. It would likely be easier to machine too.
Would this alloy have the necessary malleability to accommodate being rifled with a button? Maybe hammer forging instead?
Interesting idea to try.Cold forming/forging of aluminum is (more often than not) done with it in an annealed condition (T0). After forming, it's tempered to whatever's needed for the part's application.Problem with cold forming aluminum in a tempered condition (T3 in this case) is that it doesn't always want to stay where you're trying to get it to go. It tends to want to spring back to wherever it was. In this case, the assumption might be that you'll end up with a bore somewhat larger than the mandrel.Another thing is that when one goes hammering on tempered aluminum enough, it tends to start flaking off of the surface. However, in a barrel forging, I believe that this would tend to be more of an issue on the OD rather than the ID.I'd definitely anodize an aluminum bore. I'm thinking Type III with a Teflon seal. An anodized surface is like a microscopic sponge. The Teflon fills in the holes and increases wear resistance.
My thought process. 2024 T3 aluminum has a yield strength of 50,000 PSI and 41v50 used for machine gun barrels is only 55,100 PSI. The hardness is 75 Rockwell C so should hold up to lead indefinitely. At less than 40% the weight of chromoly a hammer forged aluminum barrel can be much thicker thus reducing harmonics like a bull barrel and still be lighter than the factory steel barrel. Thoughts?
Quote from: TroyHammer on December 12, 2020, 01:39:38 AMMy thought process. 2024 T3 aluminum has a yield strength of 50,000 PSI and 41v50 used for machine gun barrels is only 55,100 PSI. The hardness is 75 Rockwell C so should hold up to lead indefinitely. At less than 40% the weight of chromoly a hammer forged aluminum barrel can be much thicker thus reducing harmonics like a bull barrel and still be lighter than the factory steel barrel. Thoughts?No Sir, it is 75 Rockwell B scaled at RB 75. Which is RC 49. If you read otherwise somewhere, it is a misprint. Yield strength is important to be sure. However for a barrel, abrasion resistance is the most important single attribute. Particularly in our low pressure applications. Knife
No one seemed to try more than once in the high pressure/high temp/powder burning world......that doesn't exclude it from being viable in the low pressure/low temp airgun uses.Does seem to be a softer/"spongy" type metal.....not the qualities we generally look for.....but it could work.Just how much weight would it save vs a skinny steel barrel with a carbon fiber wrap?