I've got an AR-15 made from parts that's missing two parts before I can put my F2 in it, those being a hop chamber and outer barrel. Basically a Wolverine MTW but less expensive for me as I already own the engine and a number of other parts, and with cooler parts that I can just start off with.
As for a bolt action rifle, I think there's a Silo Entertainment video where he has a KAR98 that has an SSG24 somehow put inside of. Unless you're in the US you'd probably need to get as many parts as possible and make some other parts in order to get everything to work, mainly the stock and whatever fittings.
I personally want to do something similar, but more with a very nice hunting rifle style gun like a Sauer or Sako. I mainly hate how fat the receiver and outer barrel are on airsoft snipers, and want something that actually looks nice. The hardest part in all of this is the barrel, as I want it to be the same diameter and have the same taper of a real rifle, but I'm unable to find steel or aluminum tubing with the ideal starting wall thickness in order to make such a thing. My best bet would be to buy a rifle with a .338cal or larger barrel and insert an airsoft barrel inside, but there is nothing very affordable in that range on top of that being a very heavy barrel. Someday I'll make this happen, but it will probably take a while.
The rifle that is you
www.sako.global
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