AR pistol operating system

[mushroom]

I'm curious.. I have been looking at different AR pistols and other 223 pistols... Like the kel-tec a Sig and a Olympic arms "oa 93" I believe... The AR types have that tube for the "recoil spring" I believe where the others do not. I have heard about gas impingement and piston types of operating systems. Is this the reason for that tube on some where not on others? I believe I've read here the piston system is more in line with an AK operating system and in my opinion has advantages.. and maybe a disadvantage as far as felt recoil goes. I am curious as to how they feel shooting like a pistol.. like you would a 1911.. isosceles or weaver type hold and stance. would AR operating system be easier to hold on to like that? And would the weight of that tube help the balance? Thanks!

[Schuetzenman]

The tube? You mean the buffer tube sticking out the back? Many foam pad it and use it as an improvised buttstock. The Olympic A3 and the Sigs are piston driven and don't have the buffer tube so you have to hold them with your hands and arms like any handgun. Stance is your choice. I find recoil in piston rifles more smooth and elongated in pulse, they seem to move less than direct gas impingment.

[mushroom]

Thanks Schuetz!!! Yes, that is the tube I was talking about. I might have to try a keltec... As always.. I am on a budget.. hahaha

[mustangpd]

you could build your own and save some cash.

[mushroom]

What would it cost to build one? I think I've seen lowers specifically marked of course are about 100.. how much are uppers? Is there any other parts necessary? Trigger groups etc? Thanks for the input!!