Jeff Gonzalez and many of the well-informed people at Trident Concepts have this to say about rifles suppressors:
I, personally, am not a big fan of direct thread on suppressors. That said, I have 4 direct thread on suppressors. However, of the four, 2 are rimfire plinkers that go on a wide variety of rifles and pistols. The third and fourth are 100% of the time suppressors, and only come off for maintenance. They are attached any time the rifles are fired.
Suppressors do have a finite service life. On a carbine, the ability to go between suppressed and unsuppressed can come in handy in prolonging the life of the suppressor. It would only take about 3 or 4 EAG or TRICON 3 day carbine courses running the gun suppressed to start getting close to the end of that service life. I believe in training how you fight, which includes shooting a suppressed carbine. But at the same time, when it is MY money that bought it, and I went through the ass pain, and wait, I don't want to wear out the suppressor prematurely during a high volume of fire training course of fire. So often times I zero with my suppressor attached, and run a few drills intermittently with it attached. Then it goes away, and comes out, and goes away, and comes out. This way I get to train with my suppressor without putting un-necessary wear and tear on it.
I also don't like suppressors that have more than a 1 minute shift between suppressed and unsuppressed shooting. That can lead to some pretty significant problems in bad scenarios. If I get a 3" shift @ 50, by follwing that formula, it is 6" at 100, 9" at 150, and 12" @ 200. Of course, that is theory, and would need to be range validated before one could really verify it to be true. Some suppressors shift their 3" or 4", and that's it. Stays that same 3" or 4". But others do not, and by using the first example of 9" @ 150 or 12" shift at 200, we are outside of a reasonable standard of accuracy under combat conditions.
Most manufacturers of direct thread on suppressors will include in their manual to "confirm zero" each time the suppressor is mounted. Fine if it is a toy. But if it is being used as a tool, that is not always possible. the variations in torque can lead to significant zero shifts. And there have been instances where I have seen direct thread on suppressors work themselves loose. That sure is not helping your accuracy issues either. Again, if it is a toy, no drama. If it is a tool, your bad day just got worse.
There are various quality of suppressors, and methods of attachment. Everything is a trade off, and there is nothing free in this world. I have an OPS INC suppressor that threads on over a muzzle brake. By design, it gives a repeatable return to zero between mounting and dismounting. This gives it tremendous flash and sound suppression, and comes in handy for zero retention. But it also requires having a muzzle break installed, which does not do much for sound or flash suppression in the event the suppressor needs to come off.
Some might ask..."Why would you take it off of a dedicated suppressed weapon?" There are several reasons, but I'll stick to one very important one. Baffle strikes and/or catastrophic failure of the suppressor. If for some reason your suppressor/high velocity round make contact where they are not supposed to, it can cause a severe disruption in the flight path of every bullet that follows. Not to mention that it is extremely dangerous to continue to shoot a suppressor that has had a baffle strike. If there is some other form of catastophic failue, such as a round decided to exit the suppressor through the side, instead of the front, (which happens a lot after an initial baffle strike) I suppose that is "technically" a baffle strike, that took one step further. Either way, the suppressor will have to come off IOT faciliate your continued effective engagement of any remaining lethal threats. So one they raises the question of "What's the big deal, unscrew it, and drive on". That is all well and good if you solve your problem quickly. But if you don't, you no longer have anything to protect your now exposed threads. A couple of good dings to the muzzle, and the crown (now exposed) is banged up and affecting accuracy in who knows what direction. Not to mention the damage to the threads. Certainly you can have your gun re-crowned and re-threaded and usually at a minimal cost (compared to the suppressor anyway). But something to think about...........
QD attachments can be suspect as well. One of the worst designs out there is the KAC QD suppressor sold to come SOCOM untis. Failure at a rate that makes you go "Hmmmm". Not the suppressor itself (though it is not exactly anything to write home about), but the attachment method. As Phil mentioned, depending on the make/model of QD and suppressor combo.....a little extra carbon and your QD suppressor takes an hour soaking in solvent and a non-marring set of vice grips and a hammer to get off.
Then you have the hybrids, which are usually thread on, with a repeatable return to zero designed into them by stopping points, and detents that prevent them from loosening up under hard use. Or twist on attachment with an unlocking lever. SureFire has such a system, and AAC mated their very excellent Blackout Flash Hider to a couple of these types of designs. I am not a big fan of their customer service, as it is too sporadic for me, but you can't beat their ingenuity when it came to those designs. The rachet attach is one of the most solid, and consistent designs out there. And if you go un-suppressed for whatever reason, you still have a highly effective flash hider. There are certainly other good designs out there, and one is wise to identify first their intended use for thier suppressor, then finding the set up that best suits their needs.
(Disclaimer: Not a suppressor expert)
