Uh sorry buddy, with HK rifles the upper is the firearm.
So do you have a sear, a registered receiver, or a registered trigger box? What type of NFA item you have will dictate what options are available to you.What I would like to have is a shorter barrel, so when I have my supressor on it the ovrall length is normal.
This was what I was trying to ask.So do you have a sear, a registered receiver, or a registered trigger box? What type of NFA item you have will dictate what options are available to you.
I saw that, but the OP is new 'round here, and thought a direct question might get us the information we need to answer the original question.This was what I was trying to ask.
With a registered receiver there is no swapping uppers... the upper is the registered part. So you use it as-is, there is no easy do-at home caliber/configuration swapping that can be done with a registered receiver other than changing the buttstock/forearm.I have a registered receiver...
Yes, any length barrel may be used.Can I put a shorter barrel on it. It is an NFA full-auto HK93 16" barrel.
Unless the OP wants a full-auto 53.It seems like it would be a whole lot easier to build a 53 on a new receiver from a cut down kit,
It seems like it would be a whole lot easier to build a 53 on a new receiver from a cut down kit, but I'm sure one of the good builders on here could convert it to 53 length without destroying the registered receiver. It would involve cutting out the current cocking tube and re-welding a shorter one in addition to the barrel installation. Might do a bit of research on suppressors and 53-length barrels though. From what i've read, most suppressor manufacturers don't recommend it because of the sub 10" barrel length. Something about muzzle blast destroying the internals...