B&T TP9 - Suppressed use, mags, impulse, and general inf

[TOOL1075]

Oh also,

Is the fine threaded barrel guide stock or did TROS do that too?

I ask because DS Arms said there will be no more threaded ones coming in. It's all B&T/Styre/three-lug now.

I wonder if the new ones have enough material to thread?

The threaded barrel guide, threaded in M26.5x1 is stock. You are correct, DSA is no longer importing them. However, you can purchase that part from the Canadian B&T distributor for around $400. (they sent me a PDF price list).

The "lugged" versions most likely do NOT have enough material to thread. The best bet with those would be to make a mount to interface with the lugs. It would most likely be complicated and unprecedented, requiring some engineering to get working correctly. If anyone pursues that route, it will be because they are intent in marketing the end product. It doesn't seem like a weekend thing, is what I'm saying. You could always get a B&T mount and figure out how to interface a suppressor to that, though. Maybe. Not straight-forward.

You also have PM.

[csfirearms]

Oh also,

Is the fine threaded barrel guide stock or did TROS do that too?

I ask because DS Arms said there will be no more threaded ones coming in. It's all B&T/Styre/three-lug now.

I wonder if the new ones have enough material to thread?

If you need a threaded barrel pistol and you have a dealer you use, RSR Group has them in stock. They have 28 pistols in stock with the threaded setup.

CSF

[este]

TOOL1075,

Did you get some resolution on your issues?

I'm considering the TP9 right now. Not sure if I should wait on it, or it's a decent gun. Unfortunately I haven't been able to handle one anywhere, so I'm just going off of reviews (eh), and people's first hand experience.

I plan on using it with an MK-9K so I don't think the suppressor issue will be as bad.

[TOOL1075]

Not yet - but I expect I will soon. Been in contact with SWR, who is of course always responsive and eager to help.

I'll let you guys know what the overall outcome/situation is.

Hope everyone is having a good holiday!

[este]

I think my year end bonus is going to buy me a TP9, I wish there were other people that owned them, I need more review food.

[Shea]

TOOL1075,

Curious where we are at on this? I have not fired mine
very much due to seeing these results?!?!

Thanks,
Shea

[TOOL1075]

My yielded Trident tube went to SWR for FREE replacement (but I had to pay a $200 transfer tax) and it is pending as of May 11th.

I purchased a Thompson Machine SG (threaded for the TP9 directly) and it arrived at my dealer yesterday. I filled out the Form 4's for that, so should have it later this year.

Keep in mind that the damage to the Trident was NOT caused by pressure. It was purely a mechanical problem resulting from a mount with a thread length that was too long which forced a bending moment into a weak point in the can for which it was not designed. After the damage, I shot the can further, and performed measurements, and there were no strikes. The Trident was still usable, but I opted to have the tube replaced because I wanted to be on the safe side. Any time I see yielding in a metal, I become very cautious of still using it. In this case, my engineering judgment told me that it would be okay, but the little birdy on my shoulder also told me that aluminum does not nearly have the plastic deformation range of steel, and to count my blessings. $200 tax is a small price to pay to silence that little birdy.

If I were you, I would find a can for your TP9 with a large volume. The direct blow-back nature does not lend itself well to a large increase in chamber pressure duration. If you do decide to use a small can, use a well-engineered mount if firing the weapon without a stock, and modify the gun to absorb more energy during cycling, if possible - without effecting function.

edit:

I want to clarify some of the above. You don't need to use a "well engineered" mount, as there might not be any available for your can, but you may be able to use a well tested mount. In fact, it will probably be okay if your can is attached in the same manner as the manufacturer tested it. In other words, you could use an adapter similar to the first one I tried (the step-down type mount, where it goes from large threads to the small threads for your can). If you use the second type I tried (the kind that goes from the large threads to the threads in your can's tube) you need to make sure the thread length of the adapter is similar to that of whatever normally threads into the can. But, all the great mounting in the world isn't going to save your gun if your can doesn't have enough volume. Look at the can Steyr made for the original SPP and look at B&T's can for this TP9. All large. For a reason.

For others reading: The TP9 isn't really "direct" blow back, because the barrel rotates and there is a pin that guides it. The rotational inertial resistance does counteract the opening of the action, so you do get that. Almost like an MP5 - same principal, different geometry (much more simple and elegant in my opinion). However, the MP5 is very suppressor friendly, because it is easier to modify the action components to compensate for increased impulse. Such is life.

I haven't performed calculations to explain what happened on paper, but I do observe actual blast and pressure experiments on a regular basis and perform explosion accident investigations for major petrochemical companies and explosive manufacturing facilities, so I'm pretty confident in my conclusion after examining all the factors at play.

Let me know if you have any questions.

[Shea]

TOOL1075,

Thank you for the very well thought out response.

My TP9 is already SBRd and I have a TROS adapter to
1/2 x 28 and a AAC Evo 9 can but I have shot it very
little and really afraid to shot it any more with the Evo.

I am thinking the same thing you did and get a TM SG.

Please your thoughts on it and if you had a chance to
fire it, is it any quieter than the Trident. The SG has
a ton of volume and was thinking it should be very
quiet. When I did shoot the TP9 with the Evo is was
scary quiet.

Thanks,
Shea

[TOOL1075]

No problem, I'm happy to share the information.

Are you using the fixed-barrel spacer with the Evo? I would suggest using it, but I have to think about that a little....

You are using the factory piston for the Evo, so I do not think you are risking damage to your Evo. The Evo is definitely different than the Trident, but it also is a relatively small volume suppressor. You mentioned that you shot it very little. Have you noticed any erosion of the top cover of the TP9 where the brass ejects? I found that to be a tell-tale sign of over-function.

I find the recoil of the TP9 (when shooting with the stock) to be harsh when compared to my MP5. How is yours? The gun and stock are very light, and the stock is pretty stiff, so that's to be expected.

I have not yet fired anything through the SG. I wanted to disassemble it before I used it, but was unable to do so by hand at my dealer. Brooks at Thompson Machine instructed me to use a towel, etc (basically to not be a pussy - my words, not his ) and the front end cap should come off. I will probably wait until the Form 4 comes back - I don't care enough. It will come apart when I get it.

Brooks also told me that they redesigned the core - so I am looking forward to shooting it. If I had to predict its sound reduction performance, I would predict that it will have a low tone with a possible loud first-round-pop (but I am not sure). The blast chamber is rather large. If it does not have a loud first round pop, that will be neat. We'll see! The can was $400. It's a foot long, and 2" in diameter. It's a monster, but it is deceptively light. The fit and finish was very nice. I want a nomex cover for it (a cool old-school black one like on the old mac cans in the days of yore).

My Trident sounded fucking bad ass on the TP9 before I broke it People would gather at the range and watch me shoot it and the comments would basically be:

"Holy s--t, what the F--k is that?"

"Is that legal?"

"Is that a real gun?"

"How do I buy one of those?"

I hope the SG will perform as well. Other than possible (unverified) first-round-pop issues, I don't see why it wouldn't.

If I were you, I would wait until some people shoot the cans before you buy one, or you could forge ahead into the unknown like I do

[Shea]

TOOL1075,

Once again, thank you.

I am using the fixed barrel adapter for the Evo.

The gun does have a little bit of recoil but not too bad.
I have shot a MP5 but not back to back with the TP9.
I don't own a MP5, not yet at least.

We must have very similar taste, I was thinking the
same thing with a TM SG with a nomex cover. I think
Tom Bowers is making some pretty neat covers.

I think I will wait and would love a range report on your
TP9 and TM SG combo. I hope it works out great.

If I do fire it more with the can, I will keep an eye on
the top cover erosion.

Once again thank you,
Shea

[TOOL1075]

No problem, man. Forums are only worth something if we contribute useful info! I'm thinking about buying a spare parts kit from Wolverine Supplies (they are a Canadian company and a B&T distributor. I bought my folding stock from them. DSA is over priced and flaky, in my opinion).

I want to replace some parts because I think I did a number on the gun.... I shot over 500 suppressed rounds through the gun with the Trident. It was so fun, I couldn't stop.

I think the SG will be a lot easier on the gun. But yeah - call or email Wolverine Supplies. I have an old PDF price list of parts from them I can send you if you like, I just have to find it. I need to get an updated list from them.

You know the threaded barrel shroud that the barrel slides in? That fucking thing is like $400. So don't mess it up

I think there is a small-parts kit (like a normal maintenance kit of commonly worn parts) you can buy from them. If I buy it, I'll post here with pictures and stuff.

Yeah, Tom makes some cool covers, but I believe they are silicone. They probably work well, but they don't seem as cool to me as the nomex. I wear nomex coveralls when I'm on-site at investigations at work, but they are blue. If they were black, I would cut the sleeve off of one and make a cover

[Shea]

Yes please send me the PDF file to
shea.elrod(removethis)@gmail.com.

I would also pick up the spare parts kit and probably
a few other things.

I got my stock from DSA and yes what a pain!!!

Thanks,
Shea

[este]

Sweet, another member of the TP9 club.

Getting the stock is a pain is putting it mildly. DSA seems to have no idea about this gun or parts for it. They couldn't even tell me what the registered part was (which serial number of the three or four). I had to call ATF Tech to find out.

I looked at the full auto parts (sear) and can not for the life of me understand how the work. My local SOT wanted to play with it in full auto (to which I can not object) but it seems like it needs a ton of new and expensive parts.

[TOOL1075]

Shea,

I sent you the PDF parts list from Wolverine Supplies, along with their explanation of what they can and can't sell.

Sorry for the delay!

oh, yeah - I forgot to mention that there can be a wait to get the parts from them. When I ordered the stock, they were just about to put in an order to B&T in Switzerland. So, they did, and I got it.... like 6 weeks later maybe? Something like that? I can't remember. It really depends if they have inventory on-hand. But, it was a smooth transaction, and they are a pleasure to deal with. I would rather order parts from them instead of DSA who:

- is hard to contact
- very flaky about responding to inquiries
- more expensive
- will not even sell you a stock unless you send them a copy of your Form 1, which I consider to be an asshole move. First of all, my Form 1 is none of their business. Second of all, it's none of their business!

[este]

- will not even sell you a stock unless you send them a copy of your Form 1, which I consider to be an asshole move. First of all, my Form 1 is none of their business. Second of all, it's none of their business!

Agreed 100%. They may desire to be the mini ATF, but no other guns are restricted in that the parts aren't available. Not AR, not Uzi, not even HK (and they hate you).

Just from their complete lack of knowledge on the gun I'll avoid DSA. What's funny is Steyr comes up with the design, and doesn't market or price it in a position to sell well, not all their fault since the TMP is an odd pistol probably better fullauto. Then after failing at the US market, B&T buys the design, makes it possible to take a stock and a few other changes that could be cool in the US nfa market, but chooses DSA as their importer. A company who has no desire to even learn about the gun, let alone market it! No one that has seen my tp9 knows what it is, but everyone loves to hold it. I fear the B&T tp9 will also fail here in the states eventually, a shame really.

[Fireman1291]

Guys,

Email [email protected] he is doing suppressor covers now and can build ya a custom one

[TOOL1075]

no s--t? Is he doing Nomex (or equivalent?) I remember I read a post of his a while back on this forum or another that said he was not doing anything in Nomex.

[panaceabeachbum]

We just got done metering the Thompson Machine SG on the TP9 , Brooks will be posting a video and spl numbers before the evening is over.

I hadnt read thru this thread before todayand probably should have saved you quite a bit of time as I have been shooting the tp9 suppressed for a number of years. No matter which can you install on the tp make sure there is no restriction smaller than the end of the bbl (aprox 1") for the first three inches.

[Shea]

Richard,

Excellent, looking forward to the results!!! Sounds like
the TM SG is going to be a perfect solution.

TOOL1075,

Thank you for the email. I am going to order the small
parts kit next week.

What vfg are you running on yours now. I went with the
Tango Down qd stubby after trying almost everything
out there.

Can you use the sights with the Micro attached. I have
my Micro coming next week. I have been running a
Trijicon MRD for the last couple of years and think the
Micro will be a better choice.

Thanks,
Shea

[panaceabeachbum]

well, I've been shooting my TP9 with my Trident. It's pretty great, but I am having some issues.



I believe the gun is over-functioning with the suppressor. There might be slightly too much duration on the chamber pressure, which is increasing the impulse.

I know you figured this out based on your drawing and new adapter
Whats happening is the end of the bbl, which is aprox 1" in diameter is acting as a gas piston because the adapter in your first pic is creating excess pressure at the muzzle.

If you push on the end of the bbl (inside the threaded sleeve) of your UNLOADED tp9 you will notice the bbl and bolt travel together rearward for aprox 3/8" before the bbl rotates far enough to unlock the bolt and allow it to travel rearward . As you restrict gas flow at the muzzle you increase the pressure bearing on the muzzle , this introduces additional and uneeded energy that has to be stopped at the end of the recoil cycle making perceived recoil and muzzle rise more pronounced. Its the same thing thats taking place in the booster of most gas assisted recoil operated belt feds like the 1919 etc.

We have minimized this with the huge blast chamber you noted in your SG, how soon till you get a chance to shoot it?

[este]

What vfg are you running on yours now. I went with the
Tango Down qd stubby after trying almost everything out there

The Magpul rvg looks like it will fit pretty well. I wish there was one angled like the MP9.

[TOOL1075]

TOOL1075,

Thank you for the email. I am going to order the small
parts kit next week.

What vfg are you running on yours now. I went with the
Tango Down qd stubby after trying almost everything
out there.

Can you use the sights with the Micro attached. I have
my Micro coming next week. I have been running a
Trijicon MRD for the last couple of years and think the
Micro will be a better choice.

Thanks,
Shea

I use a cheap VFG - it's this one: http://www.botachtactical.com/tdiforegrip.html (order it from your favorite reliable dealer. Botach may or may not be reliable, based on what they actually have in stock lol). If you install it on the gun just right, it doesn't interfere with the folding stock in the folded position.

No, there is no way to use the existing sights with the Aimpoint T1. I don't think there would be a way to do this with any mounted optic, as the sighs are so low relative to the rail. Something you may be interested to know is that the Aimpoint T1 was developed for use on this gun. It's very good on the gun, and it's where mine stays.

We just got done metering the Thompson Machine SG on the TP9 , Brooks will be posting a video and spl numbers before the evening is over.

I hadnt read thru this thread before todayand probably should have saved you quite a bit of time as I have been shooting the tp9 suppressed for a number of years. No matter which can you install on the tp make sure there is no restriction smaller than the end of the bbl (aprox 1") for the first three inches.

Brooks emailed me about the testing - definitely makes sense that it is quiet, considering all I have learned through this experience. Yeah, the 3" or so of free space is definitely key!

I know you figured this out based on your drawing and new adapter
Whats happening is the end of the bbl, which is aprox 1" in diameter is acting as a gas piston because the adapter in your first pic is creating excess pressure at the muzzle.

If you push on the end of the bbl (inside the threaded sleeve) of your UNLOADED tp9 you will notice the bbl and bolt travel together rearward for aprox 3/8" before the bbl rotates far enough to unlock the bolt and allow it to travel rearward . As you restrict gas flow at the muzzle you increase the pressure bearing on the muzzle , this introduces additional and uneeded energy that has to be stopped at the end of the recoil cycle making perceived recoil and muzzle rise more pronounced. Its the same thing thats taking place in the booster of most gas assisted recoil operated belt feds like the 1919 etc.

We have minimized this with the huge blast chamber you noted in your SG, how soon till you get a chance to shoot it?

Yup, figured that out the hard way but now people won't make the same mistake, which is good.

I'm not sure when I'll get to shoot it. I'll probably wait until the Form 4 comes back, which could be 3-4 months, who knows.

I know this much though - it looks like you guys have cornered the TP9 suppressor market, however big it is. It's a shame they (DSA) don't want to import any more TP9's with the threaded barrel shrouds. Someone needs to come up with an attachment mechanism for B&T's proprietary lug system for the other models. It would be more expensive, and only be useful for that particular gun, but it would still be cool for some folks out there. (most are in Canada probably lol). Man, TONS of people in Canada have the semi-auto TP9, with the stock (no such thing as an SBR in Canada) but they are limited to 5 rounds in mags. Oh Canada....

Or someone could thread those lugged shrouds..... that would be interesting if possible.

[este]

It's a shame they (DSA) don't want to import any more TP9's with the threaded barrel shrouds.

RSR still has 20 or so. They had 30 when I bought mine, and that was, I don't remember how long ago. They have been on close out for awhile. If they don't sell, I would expect them to wind up at CDNN or someplace. Too bad they aren't marketed better, they're really quite interesting guns.

[ArevaloSOCOM]

With the Thompson can it's incredibley light subgun+silencer combo.

[este]

Where are the pics of SBR TP9s?