Yes,yes,and yes bellson. SAR had a great write up umpteen years ago dealing with Stoners design and barrel length vs.gas tube transferring energy to the key on the carrier. My wife asked me what I was thinking about and ten minutes in she just told me to shut up! Hard to find people that actually get any of this. Off topic, but how is the son doing with the welding course? Think about you guys time to time. Feel free to PM or maybe you still have the email address.