Just purchased a TBAC 30 BA suppressor. The Barrel I have has 9/16-24 TPI.
I purchased a thread adapter to convert from 9/16-24 to 5/8-24.
screwed on thread adapter and there is still a gap between the barrel and the tread adapter even thought it is tight. It is only finger tight at this point. how do I shim it so that ther is no gap after I fully tighten it down n the barrel. or should I get different thread adapter.
Posts: 304
Threads: 19
Joined: Aug 2013
Sounds more like a barrel problem and not a Tbac problem.
I would say the threads aren't cut all the way to the face. There is probably a shoulder behind the threads. You could get peel washers and put in between, but I would check to make sure everything is concentric before I shot it.
Posts: 2,075
Threads: 35
Joined: Mar 2011
I'm sure you know this but DO NOT shoot it like that. I know an individual that had a similar problem with a suppressor and shot it anyway. Didn't end well.
How wide is the gap? If it's not more than a few thousandths peel washers would be a band-aid fix that would work as bigbear suggested. Another option is to have a gunsmith or machinist shorten the threaded portion of your barrel and re-cut the crown. However, if you were going to go that route I would just have it cut it back and re-threaded to 5/8-24. This what I did with my Satern barrel. If you don't want to have barrel cut on then you need to find an adapter with deeper threads on the 9/16-24 female side.
BTW- Where in central Texas are you located?
NRA life, GOA life, SAF, and TSRA
"I ask, Sir, what is the militia? It is the whole people, except for a few public officials. To disarm the people is the best and most effectual way to enslave them."
George Mason, co-author, 2nd Amendment.
I've seen it before too. Thread adaptors are a horrible way to deal with cans, as you are asking for a baffle strike.
If you look on TBAC's website, they have a specific drawing for what they require for making barrel threads work with their direct thread-on cans, and we actually used that drawing in the 6.5 Grendel Reloading Handbook Volume II in the muzzle devices section.
TBAC also makes 9/16 brakes for their brake-attach cans, but it looks like you have a direct-thread-on can for 5/8x24. Just get your muzzle re-threaded, or get another barrel. This is not an area to play around with, as you will most likely get a baffle strike.
