Just wanted to post my experience with Blackthorne LLC.
I ordered a complete DPMS 308 upper, bolt and charging handle.
The company sent me the wrong parts.
The company does not have a phone number to call for customer service, only email which they will not answer.
Needless to say after having to turn them into the BBB, and disputing the charge with my credit card, I finally was able to send back to wrong part, and get a refund for my order but got screwed out of the shipping cost, but I'll take what I can get. The whole fiasco took a month and half.
They seem to have decent prices, but customer service is not existent, so if they screw up you will have to fight to get the order corrected or refund and still have to pay for their mistakes.
So Buyer Beware.