The jmac website says it will work with the 552 the only reason I am not using it is I need an 8 inch barrel and I have a 10. The gas block I have no idea the maker. I got everything in a bundle including the old school laser devices flashlight that went on the commandoI have the same JMAC retainer rings, and they allow you to use a cut-down 550 handguard on a 556. An actual Swiss 552 or 553 handguard will not work on a 556, regardless of the ring, because it is too short.
Also, who makes that gas block? I have only ever seen it once before, and it may have been in some other post of yours.
Yeah I got my sbr paperwork and was all excited to make a 552 commando and to my disappointment when my barrel was too long and it didn't line up correctly. Didn't feel like going through more paperwork again to cut it more.Copy and paste from JMAC sight...
"In order to install on this on the above 556 rifles you will have to cut down an original 550 hand guard."
And I know this to be true.
Also, a barrel swap is not an easy job on these guns. I'd advise you to stick with the 10 inch.
Your rifle is better looking and I think I'll take your advice and just find a 550 handguard and find somwonw to cut it down and fit it for mine. I wish I could have an actual sig lower but my job requires me to able to accept AR style mags.I see the issue now. You have the Xi. I have very limited experience with the Xi, so I can't really advise you on a good course of action.
UPDATE- After some people have been asking for price I had to do some research of the price and I think $225 for all three.I have a Swiss 552 handguard and a retainer that will allow it to work with the sig 556. I also have a gas block that has a folding front sight.
If your looking to create the 552 commando look then send me a message about this parts.