Well, he's taking about some top gun builders in his post when he mentions Karl Feldcamp & Robert Gradous who surely don't work cheap (I've dealt with Karl a lot) & GAP falls into the category.....................he doesn't seem to understand that other than getting some parts cerrokoted for appearance, that you can buy parts at wherever in the quality/price spectrum you desire & put them together as well as most builders.
You can buy whatever quality barrel you want from whoever, & have them fit & headspace a bolt to it, & you can buy a lapping tool for the upper receiver for just a few bucks......................pretty much all else is just assembly.
MM
