MKA 1919 Switch Uppers?

[jkpq45]

In searching for an MKA 1919, the question is--can the uppers be changed to different calibers, or would it require some serious rework of the mechanism?

Never actually handled one--I'd have to order to see.

Thanks,
jkpq45

 

[Desolo]

They are more like a traditonal gas operated shotgun with a spiffy shell and the addition of ar style ergos.

They LOOK like an AR, but dont come apart the same way or have many common parts.... any of the versions you have seen that have M-4 style stocks and the like are modifications to it that cut off the stock and install an adapter, I dont even think it has a "lower" in the Ar sense.