Ok, I just checked, and in production quantities from the mill (enough to do a run of 100 units) the cost difference per rifle would work out to about $12. Less for higher product runs.
EDIT: It turns out that if you shop around you can actually get the raw 7075 forgings, upper and lower together, for $12 total! The forge mills aparently have enough volume to get it this cheap.
By comparisson, the machine time to make, say, a billet AR, is much higher than $12.
The Core15 is likely a very nice us-made AR, but it's not accurate to say they are more expensive ot produce than machined AR's of other alloy.
this is not intended as a comment to say one is better than the other or vice versa, but the statements in earlier posts on 7075 forged lowers costing more is incorrect.
