Does anyone have a good bit of experience with OSS, Griffin Eco-Flow, or KAC QDC cans? Especially as compared to other, more conventional baffle designs? I know OSS is kind of the outlier, as it's design is a far cry from all others; Griffin's Eco-Flow seems to be the newest in the backpressure mitigation designs, and KAC seems to have been taking it into account for a while, but maybe not to the degree Griffin may have addressed it with Eco-Flow. Or maybe they're all baseless hype. Regardless, the concept interests me, as I very much dislike the negative effects of increased back-pressure. I am seeking opinions from folks that have used the above mentioned silencers; especially in instances of comparison to previous experiences with other silencers, or side-by-side comparisons. This is not my first silencer, and I'd be using it on both DI and piston guns; mostly on short barrels. Sound levels are not as important to me as cleanliness and minimal host weapon performance impact. Mount functionality and silencer barrel length recommendations are not priorities either.

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

Well, I went ahead and got an OSS HXQD 556. I am fortunate enough to have access to my pending silencers, while the stamp is plodding along, so I'll update this post with my experiences, for others who may be interested in the flow-through design.

I have a Rugged Razor 7.62 can in jail with low black flow design. My SBR host was recently approved so I hope to learn about these low back flow designs this week during my next conjugal visit.

I get the impression that Griffin’s new Eco-flow baffles are a lower back pressure than their previous baffle designs, but I don’t think they are in the same class as the OSS flow-through cans for low back pressure. Also, the OSS cans aren’t user serviceable, so you’ll have to use the “dip” or something similar. My feeling is that the OSS cans are great at one thing, very low back pressure, and kind of mediocre at the other stuff like weight, suppression level, price, etc. If you’ve got an adjustable gas block, especially combined with a piston gun, you really don’t need to go all out for low back pressure.

I was unaware of the Rugged Razor. I think my LGS has one of those, so I'll check it out next time I am there. I am certainly curious as to it's performance, so I hope to hear from you after you use it.

I guess my initial post wasn't written quite right. I did not intend to imply that any low pressure design was on the level of the OSS; I agree that they are a silencer all their own. I have yet to shoot one, but about five seconds spent looking at one in person can tell you nothing compares. If a radical design like that is truly what it takes to really mitigate back-pressure, then I don't see how any modified conventional design like Eco-Flow could even come close. User-serviceability is not a critical item for me. None of the center-fire silencers I have can be taken apart, and I have grown to more-or-less prefer it that way. I like the no-nonsense look and feel of a fully-welded silencer. I do wish I had the foresight to weigh my silencers when I got them, so I could keep track of build-up. Maybe I'll do that with the OSS. I agree with you, that the OSS is designed to do one thing better than the rest, but perhaps falls short in other categories, comparatively. At this point in my use of silencers, I want exactly that thing that they provide, so I am more than willing to give it shot. I don't think their weight is out of line though, when compared to other steel fully-welded QD cans. In my experience, which may of course differ from yours, an adjustable gas block, even on a piston gun, isn't enough to quell the gas coming back into the gun from the bore. Adjustable gas certainly serves to make the gun run properly, and cut-down on gas in the face, but the extra filth is still an annoyance.

When the HXQD556 gets here, I intend to compare it's performance to a conventional baffle can (likely a Gemtech Halo), on three different guns: an AR15 that has been optimized to function always suppressed, a baseline 14.5" Colt M4, and a Sig 553. I think that will give a well-rounded impression of the OSS compared to a conventional silencer. The comparison will be done in the context of a weapon operation, gas blowback, and filth assessment. I will not be focusing on things like accuracy or suppression level.

I have the KAC QDC CQB - the little guy. I shoot it on a DDM4v7s. I dont get as much suppression in flash or sound but its essentially indestructible. Also, i never really thought the back pressure/gas to face was too terrible with it.

I am interested in a low back pressure can for my SCAR 17s and PTR 91. Neither are really designed for suppressor use, and FN won’t warranty eventual parts breakages, if they perceive you’ve used a suppressor. The only cans I’d really trust in this dept are the OSS, as they’d essentially put no/little back pressure on the system.

However, it’s not a priority for me, currently. Performance (sound/flash) won’t be as great as baffle cans, but it should take the bark out while allowing the operation to be minimally effected.

I just paid for a Rugged Obsidian 45, so I’m not ready to put more cash down, but my next can will likely the the 762-QD or the 762 QD-Ti.

quote:

Originally posted by PorterN:
I have the KAC QDC CQB - i never really thought the back pressure/gas to face was too terrible with it.

I have yet to shoot either the CQB or the full-size QDC, but have examined both. As best I can tell, the CQB does not employ the pressure-mitigating design; probably just isn't enough room for it. I'd imagine any perceived lack of blow-back is due to the fact the can is just so short.

quote:

Originally posted by Vgex: Neither are really designed for suppressor use, and FN won’t warranty eventual parts breakages, if they perceive you’ve used a suppressor.

That is friggin weird. I was always under the impression that was the main intent of the adjustable gas on the SCAR; not to mention the images you see of supposed SEALs using/holding SCAR rifles with silencers attached to them. Seems ridiculous that FN would design a modern combat rifle for SOCOM soldiers that doesn't play well with a silencer.

quote:

Originally posted by KSGM:

That is friggin weird. I was always under the impression that was the main intent of the adjustable gas on the SCAR; not to mention the images you see of supposed SEALs using/holding SCAR rifles with silencers attached to them. Seems ridiculous that FN would design a modern combat rifle for SOCOM soldiers that doesn't play well with a silencer.

The SCAR-H issues were corrected over time with the main change being an increase in carrier weight. Unfortunately, the changes were not carried over to the commercial 17s. You can adjust the piston to the lowest gas setting on the 17s, but if using a traditional suppressor, you will still be over-gassed.

You can install an aftermarket gas jet to further reduce the gas pressure, but if you have an issue and neglect to remove it before sending in, you will be paying for any repairs out of pocket, as it will void the warranty.

Well I shot the Rugged Razor in 762 on my SIG 553 in 5.56 SB. Nice can and good suppression. Felt a little gas in the face on the normal gas tube setting. Switched to the adverse setting and there was less gas but It did feel some. Put some rounds through it on the suppressed gas setting and of course zero gas. Now it should be noted that I shot it at an indoor gun range. I shoot rifle left handed so my face is just behind the ejection port. I only put 100 rounds through it but I am generally happy with the can. I think there was less gas in my face and that was my hope.

quote:

Originally posted by KSGM:

quote:

Originally posted by PorterN:
I have the KAC QDC CQB - i never really thought the back pressure/gas to face was too terrible with it.

I have yet to shoot either the CQB or the full-size QDC, but have examined both. As best I can tell, the CQB does not employ the pressure-mitigating design; probably just isn't enough room for it. I'd imagine any perceived lack of blow-back is due to the fact the can is just so short.

Perhaps you are correct. The 8 baffles i count seem to be pretty close together, but appear to be asymmetrical and probably deliberately stacked as to let the gases flow around the outer sides of the baffles, slowing them down but not stopping them. The signature and flash reduction is not the greatest on the market, as MAC reports with much disappointment in regards to cost. But as Garand Thumb says, the KAC and Surefire cans are his top suggestion for the best of signature reduction mixed with bomb-proof longevity. Having shot the suppressor on an 11.5” in low light, the flash is definitely lessened but randomly still spits some spark, similarly to the Surefire Mini2 in many of GT’s videos.

In looking up KAC’s technology with backpressure in mind as you brought up, i found a citation of their “Pressure Reducing Technology” referenced on another forum in which an alleged KAC employee describes the tech and the R&D of the suppressors; he says the following:

“A whole lot of the retained pressure held in the bore and suppressor is released after projectile transit, and prior to extraction; which makes the suppressor addition way more neutral in operating system effect. Since the operating system isn't getting that bore pressure boost, the buffer impacts at less speed (lower force= lower recoil), and baffles are naturally a brake, they just don't feel like it because of the recoil increase (brake effect=lower recoil).”

While the CQB version isnt mentioned by name, and the effect he describes is potentially aided by a shorter and, if you want to call it a “less effective” size, I cant imagine this “PRT” technology, design, and testing would simply be tossed by the wayside to any degree purely because it wont fit in the short OAL of the can. If i had a bore camera or Xray, id love to more closely see the technology and flow-thru design of the CQB I own, and/or discuss it’s effectiveness and design with the creators.

Although there may be some handoff between the short length and some level of pressure reduction, just as there is a tradeoff between size and signature reduction, I still think it is a very effective suppressor given my personal experience with it and other suppressors, as well as in the bigger picture that is signature reduction overall, beyond just a Db test. Regardless, you’ve absolutely brought up some great points and, while I cant say Ive always been in love with what was an impulse purchased suppressor, I have grown to love it for what it is and appreciate it, its design, and effectiveness in my experience the more I shoot it and research it.

quote:

Originally posted by gw3971:
Well I shot the Rugged Razor in 762 on my SIG 553 in 5.56 SB.

Good to hear it performed well. I had a chance to look at one yesterday, and was intrigued by the GENEROUS initial chamber. The baffles themselves seem more-or-less conventional, but I know there's more to silencer performance and design than meets the eye.

quote:

Originally posted by PorterN:
I have grown to love it for what it is and appreciate it, its design, and effectiveness in my experience the more I shoot it and research it.

I hope I wasn't perceived as knocking the CQB. I appreciate it as well, and am a strong proponent of the "take the edge off" mentality, which is the intent of those cans. I was fortunate enough to shoot a full-size QDC today. I compared it directly to a GMT-Halo and the new Griffin GP-N. Suppression levels were too similar to pick a winner or loser, but the QDC did strike me as perhaps a bit quieter. I did notice that the GP-N seemed to have a softer recoil impulse though.

It is wild to compare the CQB to the regular QDC, strictly visibly. The CQB, as you stated, has a lot of baffles in that tiny space; about double the baffles of the regular QDC. There may be some of the low-pressure tech in the CQB, there's just not anything unique readily visible, as in the full-size.

OSS HX-QD arrived today. Should be able to mess with it soon. I'll share my initial impressions, and refine my opinion over time. I'll be using it on a SiG 553, which has been used almost exclusively with an early Gemtech HALO up to this point.

Actually, after I thought about it more, I may not be able to use it on the 553, due to the lack of a good shoulder on the muzzle of that gun. The HALO on a Smith Vortex has been fine, as the muzzle device just bottoms-out against the face of the muzzle. I don't think that'll be possible with the OSS device.

Considering the 553 is off the table for now, I installed the OSS on a Sig 516 7" piston gun. Initial impressions are...

Due to stuff in the can left-over from manufacturing, or lubricant in the barrel of that gun, the first few shots were particularly smoky. This allowed me to see all the gas being pushed out through the silencer, which was neat.

I shot a 12-shot drill twice. This particular drill will make my eyes sting with most guns; piston or DI, tuned or not. No sting to speak of with the OSS, so that seems like a win.

I am a baby, and wear ear protection when I shoot with silencers. I shot one round without ears, and it was uncomfortable. Granted this is a can known to be a bit louder, and on a 7" barrel, so I guess that's to be expected.

The mount interface is cool, but maybe leaves something to be desired. It is reverse-thread and seats against a taper on the FH. No redundant latch mechanism. The silencer is "self-tightening", so it shouldn't come off during firing, and I don't think it will. I had read reports of the can being very difficult to remove when hot. I don't care so much about that, and have yet to try it. I waited for it to cool, and it spun right off. What I see as a worrisome aspect is the potential for the silencer to back-off before it is fired and tightens itself. This will require more time with the can, to determine the validity of the concern.

More time will be spent in general, to determine the full range of pros and cons of the HX-QD. Especially once I can get it installed on the gun I intend to use it with.

Neat. Thanks for the report. I am hoping the integrated flash hider if the 556-QD trickles down to the 762, before I make my purchase. I wouldn’t worry about being a baby. You only get ears once.

The OSS representative that my LGS spoke to said that the 7.62 cans are getting the flash hider treatment in the very near future.