Originally Posted by gunnut07
That is because some companies contract out for their lowers marked with their roll mark and serial numbers. One manufacture might make 12 different lowers for 12 different companies but all the lowers are the same except for the roll mark. I forget off the top of my head who does this.
if you want your own roll mark it will cost you. As with anything the bigger the order the lower the price. If you want 1 custom engraved lower it will cost you more than if a company orders 3k of them.
The biggest Manufacturers for making lowers are: MMS, CMT, LAR and LMT. There may be others, but these are the best known and trusted. Go to AR-15.Com and look under AR Lower Receiver FAQ to find what Companies use which Manufacturer----very informative.
Some of these manufacturers have made (older) lowers for 1 company while another manufacturer now makes the (new) lowers for that same company, so there is swapping back/forth. There are some sudtle differences of flashing on many of the lowers between the Manufacturer's, while another Manufacturer cleans up their flashing/forge joints before exterior anodizing.
As to having a custom "Roll Mark" on just one lower and it's cost, just find a Tattoo Artist and let them use a dremmel tool and diamond bit to give you that custom picture you want. Of course it'll take away the anodizing and leave the raw aluminum alloy under it, which will give it some bling. I'm thinking of letting my SIL(Tatter) do some custom engraving on my AR when he and my Daughter come in this Thanksgiving.