clynch

No. The M1/M3 and M4-pattern stocks are not interchangeable. There is a Straight / Field stock on GB now also, but it has been bid up to rude money...

This one is pretty straightforward - in your case you would just spin the Field stock into place rather than the Collapsible: http://m.youtube.com/#/watch?v=lpkKyPwHxNI&desktop_uri=%2Fwatch%3Fv%3DlpkKyPwHxNI Hope this helps, Clint PS: I'm not affiliated with Ratworx in any way - just found their video first.

If I understand correctly you are looking for the Straight / Field stock for your M4, right? Not a non-collapsing Collapsible? If so then no, you don't need a different tube - the Field stock spins on and off per the usual method.

PM sent. Thanks in advance, Clint