Are the factory suppressors anything to write home about? Would it be difficult to fit a suppressor other than the factory ones? Im torn about what to do here, mostly because of the funky threading.

Narrowing down my choices for a m11 mg and im thinking that the can, while a huge bonus, may not be a deal breaker up front.  As long as I can still put something on it.

What do you mean by "factory" ?

The vast majority of M11s are M11/9s which were made by SWD. (save the old MAC/RPB M11s in 380)  

Any "factory" suppressor made by SWD would be 20+ years old and ancient technology via wipes, spiral diffusers, and brass eye-loops.

If you are picking up a transferable M11/9 you might as well get a modern suppressor to go with it.  If you are talking about "factory" vs. a homemade Form 1 build suppressor than there are plenty of factory modern options available now-a-days that will fit the M11/9 Series.

There are dedicated subgun suppressors like the Gemtech Viper or Bowers Vers 9 that can  fit the factory M11 3/4x10 threads that will be right at home on an SWD M11/9.

There are no shortage of other modular suppressors offerings like the AAC Tirant 9(M), Silencerco Octane 9, or Gemtech GM-9 that can be used with the M11/9 by purchasing either an upper with a 3-Lug barrel (and using the appropriate HK style 3-lug adapter) or buying a barrel that is threaded 1/2x28 and use one of the fixed threaded mounts plus associated LID spacer.  These modular suppressor while full auto rated have less internal volume than a dedicated subgun suppressor so will have more backpressure vs. a dedicated subgun suppressor.   However, they can also be used on a handgun with the proper LID mount as well as other subguns (MP5, EVO9, Colt M16/9) where specialty suppressors like the Gemtech Viper cannot given its dedicated 3/4x10 mounting arrangement.

I would be hard pressed to even bother to pay the transfer tax for a 1980s vintage subgun suppressor unless you just happen to want a collectible.  I actually picked up a MAC10 as part of a transferable machinegun package deal back in March and was offered the 80s era can that came with it and refused to take it as it wasn't worth the $200 transfer tax to me.

This is very good info for me thank you. The suppressor is marked Rpb.

I have seen several with "original" suppressors but your advise seems sound to me. Thanks again

Ultimately its your call.   A RPB can is most likely going to be even older than a SWD suppressor since RPB went bust before SWD formed.   ( not that there is much difference between late 70s and early 80s suppressor tech.)

If the RPB can is in-State with a single transfer tax and is otherwise "free" its maybe a wash for the $200 single transfer tax.  

Technically, many of these old suppressor can be rebuilt to a more modern "wipe-less" design by folks like Tom Bowers, but that is a lot of effort and cost vs. just buying a new modern can to start with.

If its out of state and a double F4 tax proposition and/or you have to actually pay anything for it I would pass.  I cant see any circumstances where a 1970s era RPB can is worth $400 in taxes, an in State NFA dealer transfer fee,  and a year wait to get it....but that is just me.

Unless there are nostalgic reasons, I wouldn't bother with the original style cans.  In my case, I did buy an original Powder Springs M10/45 can when I bought the gun because it had been upgraded by Bowers and was serial number matched to the gun itself.

I actually like the early Sionics 2-stage cans.....eyelets/spiral diffusers/wipes and all. I still use a Sionics .45 can on my Uzi (had a bbl. nut adaptor with 7/8-9 threads made, and cut the bbl to "FBI" length). To my ears it is as quiet as the Bowers can a friend has on his Uzi.

I thought about sending it out to have a wipeless end cap installed...or possibly recored with 60 degree cones......but why mess with it if it works ?

The later RPB / SWD cans to avoid were the ones where both stages had the same diameter tubes.....with wipes at the back and front of the 2nd stage.....even with fresh wipes they don't sound good.

Guys, whats a wiper I don't know what that means? Ive recently stepped into the Nfa game so my knowledge is infantile at best.

The one can i do have spills 7 thin cones when I disassembled it, are the wipers related to the baffles or something?

Parts #12 and 14 in the pic......think of them like thick urethane washers....with a bore diameter slightly smaller than projectile diameter.....the projectile "squeezes" thru them......aids in trapping/slowing down exiting gasses.....meant to be replaced frequently


Very informative thread at Uzitalk on the Sionics/RPB/SWD cans here:
http://www.uzitalk.com/forums/showthread.php?27755-For-Sionics-Suppressor-Owner-s

I've got 2 original 2-stage cans that I run on my M11/9 and MAC10/9.  I've made new wipes.  I've read that they are louder than modern cans, of which I have a pair of Advanced Armament TiRant-9, and I'd say it is pretty close, at least until the wipes wear out.  Subsonic ammo with the original cans produces a very soft thud sound when fired, which I find very pleasing.

I wouldn't buy the original can unless the gun was an original early 1970s production MAC 10 and had the original matching numbered two-stage can.

There is no reason to buy some lame 1980s can to go on your m11

buy a modern subgun can, there are a few excellent choices

I got the bowers CAC9 for my M10 and it eventually went on my UZI with the excellent bowers UZI mount that replaces the barrel nut

I would love to see one of those original cans tested against a modern can with a proper sound meter

suppressors have come a LONG way


OP,

call Bowers and ask about having a modern baffle stack put in your old can

big improvement in suppression, and no dicking around with wipes (assuming your can has them)

FWIW, I think the original two-stage cans are cool as all get out

they look perfect on a MAC

but they were cutting edge technology... almost 50 years ago

I do miss my MAC10

https://www.youtube.com/watch?v=_GfJSxMr5TU