My brother has a sig srd22x and wanted to know if he could safely run subsonic 5.7x28 through it. He's got a PSA Rock w/factory threaded barrel.

This message has been edited. Last edited by: BPopp,

I'm not a sig suppressor fan or user, but on a quick look I don't see a model SRD22 only SRD22X. And if that's the case no.

A review comment on the SIG Sauer site about the SRD22X:

“DO NOT SHOOT 5.7 THROUGH THIS
I just got my SRD22X and had questions about it. He took it apart and reassembled it, showing me how to use the tool (I did not ask him to do that). I asked if I could use this with my Smith & Wesson M&P 5.7.The employee at Action Arms said "yes, of course" that evening I shot it at my friend's early 4th of July celebration. When I got home I noticed the end cap was struck. I'm going back to the Sig Dealer to solve the problem tomorrow. I wish I did my own research. My Silencerco Sparrow is rated for it and thought what a Sig Sauer dealer said was correct. Luckily the only other review of this product had the same issue and Sig Sauer handled it correctly. Be careful who you listen to. Sig Sauer needs to put a red flag to not use 5.7.”

https://www.sigsauer.com/srd22x-1.html

On a technical level I would be unclear what a end cap strike has to do with the situation. I would be interested in others thoughts on that. But it is completely clear that sig does not list it as acceptable.

quote:

Originally posted by hrcjon:
On a technical level I would be unclear what a end cap strike has to do with the situation.

A good point that I wondered a little about myself.

Is it possible that the 5.7 bullet isn’t fully stabilized at the muzzle of a short barrel? The ballistician Bryan Litz has discussed that a little (not pertaining to the 5.7) but I don’t know to what degree the bullet might be yawing at that point.

The few times I’ve been concerned about that possibility I fire a few rounds through witness paper at close distances to check for any signs of excessive yawing.

Added: I just noticed the reference to subsonic load. It would be useful to know the specific ammunition and the bullet weight used by the individual who posted the above review. I see from a little research that the M&P has a 1:9" rifling twist rate. The one factory subsonic load I found uses a 62 grain bullet, and although 1:9" might stabilize it okay, there’s a greater chance that it takes a little flight distance for it to “go to sleep,” i.e., minimize yaw.

The Applied Ballistics data for the Lake City 0.224 caliber 62 grain FMJ bullet that might be similar to what was used by the person who posted the review states that the minimum twist rate for the bullet is 1:9.1 inches and “the recommended twist for optimal performance” is 1:8.2" or faster. All that really makes me suspect that the end cap strike was due to inadequate bullet stability and excessive yaw at the end of the suppressor.

I am unclear if the review comment you posted was of a subsonic load. They are a bit unusual.
But one can compare circumstances and many .22lr cans support 5.7. Like for example the DA mask and Rugged occulus that I personally have. One would suspect if subsonic was in and of itself an issue you might see some notes about that. But one thing about the M&P in that post is that it has a pretty unusual system for suppressor attachment and I suspect that is the core issue there is an alignment issue. nothing to do with the round or suppressor. The factory FN guns have 1:9 twist rates so I'm thinking that its unlikely that is on the ragged edge of stability.
In any case the OP doesn't have any of these issues...

Thank you very much for that clarification. I've heard so many opinions on it from people who have questionable knowledge that I needed some better advice. I will NOT be using it for that. Thank you.

quote:

Originally posted by sigfreund:
It would be useful to know the specific ammunition and the bullet weight used by the individual who posted the above review..

So, yes, we don’t know if the reviewer on the SIG site was using subsonic ammunition even though that’s more likely when someone is using a suppressor. If he wasn’t using that ammunition then my comments about an unstable bullet might not have applied to that situation.

There are other possibilities that would have explained the reviewer’s experience, including a misaligned or even loose suppressor.
A couple of other less likely possibilities would have been a bad bullet or even a problem with the gun’s barrel. I didn’t get into those, though, because they were not really relevant to this thread’s question.

On the other hand, our OP specifically mentioned shooting “subs,” and therefore my comments would apply and that’s why I made them. All that would apply even if the SIG site review had never been made.
But do a lot of people successfully shoot 62 grain bullets from 1:9" twist barrels? Sure. Is the caution about the minimum twist rate for assured stability of one particular 62 grain bullet therefore something to be aware of? No, not if we don’t care about the possibility of an end cap strike when using a suppressor. Shoot and be happy; the guy who published that data is probably just trying to scare us.

In rereading everything I realize that my post above with the technical details about bullet stability could have been interpreted as referring only to the SIG site reviewer who complained about an end cap strike. It was intended to discuss shooting subsonic ammunition in general, and with a particular subsonic load.

Sorry for the confusion.

I'm still a little new to suppressors in general. I've only owned one for about 2 years now and about to buy another but I'm trying to do more research on the next one. I really appreciate the responses.

In my experience, the material construction is the differentiator between .22 suppressors that can handle 5.7, and those that can’t. In general terms, suppressors made of stainless steel can handle the much higher pressure of 5.7, while aluminum ones can’t. Cans like the Mask and Oculus are made of stainless steel, are full auto rated, and specifically say they are rated for 5.7. I believe the SRD is made of SS too, but Sig doesn’t list it, so I wouldn’t chance it personally.

Regarding the review comment on the Sig website, if the pistol used was the S&W M&P 5.7, be aware that the threading isn’t on the barrel itself, unlike it is on the FN, Ruger, and others. S&W threaded the barrel shroud that the actual barrel slides in, so the suppressor isn’t actually attached to the barrel. That can lead to concentricity issues. Chances are that the reviewer would have had a strike with any .22lr suppressor on that gun if it wasn’t concentric.

Also, who’s to say that the guy with the strike checked tightness during the shoot? First time I shot my Oculus on my CMMG 8” upper, I got an endcap nick. I checked the bore before shooting, and first mag went fine. I then checked tightness, and it was good. Next mag and a half, it happened. Afterwards, I noticed the can was slightly loose. Long story short, getting an endcap strike doesn’t mean that the can isn’t rated for the round (unless it’s an obvious size mismatch).

On their web page Sig describes it as a rimfire suppressor rated for 22lr, 17hmr, and 22 magnum. 22 magnum has a maximum pressure of 24k psi.

5.7x28 is a centerfire cartridge with a maximum pressure of 48k psi. Subsonics run about 30k.

Do what you want, but I wouldn’t risk it.

Better question then... which suppressor do y'all prefer to use for 5.7x28?

quote:

Originally posted by BPopp:
Better question then... which suppressor do y'all prefer to use for 5.7x28?

On a handgun or PCC? For a handgun, I’d use a DA Mask or Rugged Oculus, making sure to check concentricity and tightness. For a PCC, I’d use a 5.56 can with a better mount than direct thread.

On my FN handgun I run a B&T 5.7 since it doesn't need an adapter (but it would be fine with a mask or occulus if you have native 1/2 threading). On my P90 I also run a B&T since that uses the flash hider mount so no adapter needed but again would be fine with anything rated for 5.7. On my short barreled 5.7 AR I run one of my 5.56 cans. Currently a ventum because its the shortest lightest thing I have. Using Xeno if that matters.

I have a PSA Rock which has a true threaded barrel, a Ruger57 that has an adapter and an Aero Precision AR-57 16". I really like the PSA and the AR57. I also have an FN PS90 but its not threaded.

I absolutely love my Oculus. Never shot 5.7 through it though. On 22LR it is ridiculously quiet, it's all steel, built like a tank, and its user serviceable.

The only negative I could mention (and it's not a big deal to me) is that it's a heavy little can compared to something like a GM-22. 7 whole ounces.

I keep hearing that name, Oculus. Believe I will go for that one since I need a rimfire can. My brother got his when he worked for a local gun store when Sig was having the buy one get one free promo. He bought the SRD762-QD and got the SRD22X for free. I've kicked myself several times for not doing it at the time but I didn't have the money.