How big and where is the whole for the port door spring is. Also what are the measurements of the the flat areas on the charging handle. I need these so I make some changes to a 604 upper to make it more like a 601
Posted: 1/12/2009 1:09:30 PM EDT
[#1]
I would like to know this also - my buddy just bought a 601 upper and I just looked for the hole - don't see it. Of course, it's been refinished, so maybe the hole got filled? If it turns out not to be 601 he's going to be pissed.
Posted: 1/12/2009 2:54:58 PM EDT
[#2]
There was a great thread here on 604-601 conversions, but I think it went into archives and never got tacked...like it should have.
It was great but I did not remember any measurements.
