Hi all, just wanted to get some opinions on an upcoming project. I acquired a Fleming sear, so I want to get a beltfed machinegun host. Looking towards the Hk21 and wanted to know what opinions you guys had on barrel length. I can go with the standard HK21 with the 18" bbl, HK21 with the 14" bbl, HK21E with the extended shroud on the 18" bbl, or the HK21 with 8". What do you guys think? I’m more of a function over form guy and I’m worried about velocity loss with the short bbls…
There is no reason to do anything shorter than the standard length.
51Bs can be fun to own but they are entirely impractical for anything beyond making noise and producing giant fireballs.
Standard…21’s aren’t the smoothest operating guns, meaning they can be brutal compared to a gas operated design.
I think you’ll have less opportunities for issues if you stick to the standard barrel.
I imagine he will sound off when he sees this thread but KevinB is well versed on the 21 i believe.
I don’t know a lot…but my dog has one.

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LOL K9 machine gunner…that should freak the Durkas out;)
Steyr, thats a nice pic you got there. What kind of ammo you run through it? I plan on just buying up lots and lots of South African surplus at the local gunshows. I think I will just get the regular 21 Shroud and 18" bbls. Thanks for the input guys! I’ll post pics when I get it from Mike at TSC.
Mostly Hirtenberger and Portuguese.
Steyr- That’s not fair; your dog has a 21 before I do. I bet that is a lot of fun to shoot. Hope I can purchase one within a year. Nice, nice gun.
Kimbo- We’ll need pics. Congrats! 21’s are one of my favorites.