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Transplanting an hk piston assy

3829 Views 8 Replies 8 Participants Last post by  CoolHandPuke
This may sound nuts... Has anyone ever built an AR using an American barrel, lower receiver and upper receiver but retrofitted the HK piston system (gas block, piston assy, barrel nut, 'channel' tube (metal cylinder which passes through the upper, providing a channel for the piston rod to go through the upper receiver and impinge the bolt carrier), and bolt/carrier assy?Looking for a project!Thanks!Charles
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Thanks for the input

Thanks to all who took the time to reply! This is more of a "see if it can be done" project for me. I am trying to adapt a seekins precision upper / gen 2 lower to piston operation (billet construction, ambidextrous bolt release, and it looks cooler).I have a couple 416 uppers and spare parts as well as lwrci rifles/parts. Having studied the retrofit piston systems, I've found them all lacking compared to lwrci and HK, so when I wanted to build my own piston gun, it was a natural choice for me to try to adapt one of these to my own upper. The HK was my first choice due to the firing pin safety system / no lite primer strikes and the beefier gas block. However, as several above have printed out, HK modified the receiver (beyond the piston channel, which is enlarged and incorporates a stainless steel insert, just like LWRCI) to include an indexing notch for the rail system. LWRCI uses a standard upper (with the piston channel). I'll post the progress...
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