Fails to extract - hard locked bolt - Radical Firearms Complete Upper Assembly .450 Bushmaster, 15in MHR, Single Ramp, Black, Box

Received the upper after some delay (10 weeks). Fits well on the lower, bolt is a little stiff, but workable after cleaning. Firing at the range, it is very accurate. However, the fired cartridges will not extract, basically have to disassemble the rifle after every shot and tap the bolt back to get the case out. I have found that if I take the spent cases, and clean the soot off, they will extract with some resistance manually. No problems feeding or extracting unfired rounds. So, before I give up, I will keep cleaning and scrubbing the chamber. For hunting season, I think I could only count on it as a single shot rifle.