This is my first post here so be nice. Heres my story leading into a few questions. I ordered a cheap 4 pos. stock I was going to use for an AR style stock for my 10/22. I decided instead of building a look alike, why not build the real thing!! So anyways, my stock showed up today and I noticed the buffer (just the buffer) has something in it when you shake it. Is this normal? Also its not completly round but has 3 flats on the rear of it. Also is this normal? I'm fairly shure I will have more questions before my build is done but thats why we are all here, to answer questions and show off how cool our projects turned out.

Welcome to the forums.
The something inside of your buffer, are the weights. Perfectly normal.
The 3 flats are normal also. They make removal/installation of the buffer, in the reciever extension easier.
If you do not yet have one, I recommend you get a military TM on the M16. Lots of good info on field stripping, and re-assembly, general maintenance, care and feeding, ect.

Thanks for the reply. I will have to track down one of those manuals. I have been spending some time reading here and I feel I should have no problems assembling the rifle.

Quoted: Thanks for the reply. I will have to track down one of those manuals. I have been spending some time reading here and I feel I should have no problems assembling the rifle.

See the  "INFORMATION"  just above  "HOMETOWN"   up there to the right ?  Touch  it,  and a list will pop-up,  click "Manuals & Downloads", select the  TM from the next list I think it is.