HauptmannAmerika
Member
I have recently fallen in love with SIG rifles and wish to add a 556 SBR to my collection. However, I don't want to buy a factory-built SBR (552-style) from a dealer. I've seen a lot of posts on this and various other forums about converting a 556 pistol to an SBR, but none about converting a 556 Patrol rifle to an SBR. The way I figure it, I have a few different options when I buy the rifle:
1) Chop the barrel down to whatever length after I've gotten the stamp back from the ATF.
2) Find another (shorter) barrel and have a gunsmith drop it in.
or
3) Buy a pistol and simply swap the uppers.
Problems I see with these ideas are as follows (respectively):
1) I probably will have problems having the end of the barrel re-threaded, as the SIG barrels flare out on the end to accommodate standard A2 flash hiders.
2) I have not been able to find any vendor that sells short SIG barrels and I'm not sure that anyone even makes them.
and
3) I read somewhere that SIG puts their serial numbers on the upper receiver rather than the lower (this is the case for my SIG 522), so the swap would most likely not be possible if that's the case.
So, what I'm asking is...
Which one of these choices is the most viable (not necessarily the cheapest, but cheap would be nice) option? Or is there another that I've missed?
Keep in mind...
The reason I don't necessarily want to get the 556 pistol and convert it is that I want the SIG lower receiver with the SIG folding stock, not a buffer tube and AR-style one.
Any and all advice is greatly appreciated!
Thanks,
Gabe
P.S. Does anyone know if the lower receiver from a SIG 522 is the same as one from a 556 rifle? I assume the trigger assembly is somewhat different, but if it's not, that's good news.
1) Chop the barrel down to whatever length after I've gotten the stamp back from the ATF.
2) Find another (shorter) barrel and have a gunsmith drop it in.
or
3) Buy a pistol and simply swap the uppers.
Problems I see with these ideas are as follows (respectively):
1) I probably will have problems having the end of the barrel re-threaded, as the SIG barrels flare out on the end to accommodate standard A2 flash hiders.
2) I have not been able to find any vendor that sells short SIG barrels and I'm not sure that anyone even makes them.
and
3) I read somewhere that SIG puts their serial numbers on the upper receiver rather than the lower (this is the case for my SIG 522), so the swap would most likely not be possible if that's the case.
So, what I'm asking is...
Which one of these choices is the most viable (not necessarily the cheapest, but cheap would be nice) option? Or is there another that I've missed?
Keep in mind...
The reason I don't necessarily want to get the 556 pistol and convert it is that I want the SIG lower receiver with the SIG folding stock, not a buffer tube and AR-style one.
Any and all advice is greatly appreciated!
Thanks,
Gabe
P.S. Does anyone know if the lower receiver from a SIG 522 is the same as one from a 556 rifle? I assume the trigger assembly is somewhat different, but if it's not, that's good news.
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