Hey, I have bought 4 lowers from you one DPMS and three CMMGs. They have all worked 100%. Yall Installed the lower parts kit on all of them, and yall installed a 6 pos M4 stock on the DPMS. I have had it for almost a year(not really sure when I bought it). Today I was shooting it and I had 3 light primer strikes in a row. I unloaded the gun and took it apart. When I was seperating the upper and the lower the buffer and spring came out. The spring and deten that hold the buffer and spring was missing. I got the gun apart and found the spring down in the trigger parts and the deten was stuck between the hammer and the bolt hold open. I geuss that is why it was not hitting the primers hard. It seems that the part of the buffer tube that covrs part of the hole that the deten sits in was broken. It seems strange to me that it would break here, and it broke in a perfect half circle. I almost looks like some one did it with a drill. Have yall ever heard of theis happening before? Does not seem like there would be alot of stress on this part. I am about to order four more lowers from yall so I guess I will need a new buffer tube too.