Originally Posted By: DultimatpredatorAre 308 lowers all created equal? I need a DPMS style. Never bought a stripped lower before. It seems like they are all the same to me. Just a fifty cent piece of cast alloy with a serial number stamped on it. Anyone have experience with some of the aftermarket 308 lowers that could provide any suggestions?
There were really two differing designs in the bigger caliber, .308 chassis, due to the length of the BCG. The first was the AR-10, which uses a standard buffer and a modified buffer tube. This created a problem with interchangeability between AR-15 and AR-10 components sine you had to have a unique butt stock design.
The other design was DPMS LR-308 which uses standard buffer tubes and stocks, but must use a different buffer. This allowed builders more freedom in choosing buttstocks and more parts interchangeability.
Most manufacturers today are building off the LR-308 platform. That being said, most of the billet lowers are interchangeable with the billet uppers and many of the forged uppers. Be careful, there are a few of the DPMS "high rise" style of uppers out there, that have an elevated rail, as well as a few hand guard mfg's.
Forged lowers should work with the forged uppers, but crossing that over with billet might be hit or miss since mfg's can specify more features on billets than with forged lowers.