Transplanting an hk piston assy

clancelotta said:

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

Click to expand...

That is in fact how the first HKM4's (HK416's) were developed. HK took US Govt "loaner" M4's and modifed them with an HK-made CHF barrel, op rod gas system and bolt group. The same was done with a Dutch-built original AR10 for the first shooting HK417 prototype. While it can be done I would not "try it at home". One of the drop in kits mentioned herein might be a better choice if you want to convert a DI gun to op rod.

G3Kurz