Not all lowers are created equal. 7075 T6 is the standard - it is much stronger than 6061. No one making 6061 lowers deserves any of your time or money. Just like everything else it comes down to the reputation and documented end user experiences of the company in question. Colt (of course), BCM, Daniel Defense, Aero, Mega, to name a few, all make good lowers and other products in general. I don't think many people here will recommend an Anderson lower - No personal experience with them but I've followed some threads where its obvious they are not well liked.
As you mentioned many companies outsource production and simply have their logo stamped on the finished product. CMT does a lot of machine work for the consumer firearms industry. The thing about contracted machine shop work is that the shop will produce the product to whatever specs they are given and that information is almost never made public. That's where the difference lies. Reputable companies are going to adhere to the specs set forth in the orignal Colt TDP as best they can, others will cut corners where they can (anywhere they can) to save a few pennies. So again, it comes down to reputation.
You can find drawings for lower receivers online, don't know how accurate they all are, but it will give you an idea of the degree of complexity. Granted, in today's world there are things much more complicated but there are plenty of areas to go worng, not just pin fitment.
Last edited by Eric D.; 07-03-17 at 13:31.
B.A.S. Mechanical Engineering Technology
Bookmarks