Does anyone here have experience with these silencers? I have been very interested in one for a little while now. The weekly silencer writer on TFB consistently refers to the AEM5 as the quietest 5.56 silencer he's ever used (granted it's on a MK12 setup; not something shorter). I think the reflex aspect is a cool way to maximize internal volume and create disruptive flow patterns, all while maintaining a deceptively long barrel; the penalty is, of course, weight. The build in my mind's eye is a mid-length gas gun, with just enough barrel past the gas block to accommodate the collar and mount for the can; I think that'd work out to be a ~14" barrel, with the can probably bringing it to ~20". The Otter Creek OCM5 is lighter than the Ops and Allen silencers, which would mitigate that weight issue a bit; considering I am not building a "clone" gun, I would be primarily considering the Otter Creek, to save that weight and some money.

Does anyone on here have any opinions on these silencers? My bottom line goal is to make a very quiet 5.56 gun that is still handy enough to not be better suited to a DMR role.

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

I just took the leap and have an OCM5 waiting on a Form 3 to my local dealer. Mine will be going on a PRI MK12 Mod H. I went back and forth between the OCM5 and AEM5, but everything that I read pushed me to go with Otter Creek. It's lighter, is said to have less blow back, and is also supposed to be quieter than the originals due to an updated baffle design. Like you, I'm not concerned about the clone aspect and only want the best performance.

Your build plans sound more NSW Reece-ish to me which would be an awesome setup. I'm considering building my own interpretation of that at some point using the Allegheny Arms tapered gas block now that I have this can on the way.

https://www.dwilsonmfg.com/All...as-blocks_p_133.html

That tapered gas block is slick, but I am a fan of PRI flip-up sight gas blocks, and use them on other guns already; I intend to use one on this prospective build too, so I'll need to use a collar. Considering PRI's involvement in the MK12, it seems they'd do well to integrate that taper into a version of their FSGB; that'd be cool.

After googling the NSW RECCE rifle you mentioned, I can tell you my intent is to create something hopefully lighter and a bit shorter than that. My build will not be free-floated either; more of a focus on near-mid range with good suppression, than mid-long range and accuracy.

OCM5 is waiting on it's form3. Barrel is on the way to ADCO for cutting, rethreading, contouring, collar install, hider pin/weld. Other build pieces are either on the way or already standing by. I expect the silencer to arrive at LGS about the time I get the barrel back. Ordered a BRT gas tube; I asked for their recommendation, based on the specs and intent of the build. I am optimistic about the gun, but I've been wrong enough times before, that it is a cautious optimism. Even though the components list be outwardly impressive, it's no indication the finished product will run as desired. The functional pieces are as follows; muzzle to butt.
OCM5 silencer
Smith Vortex Ops Inc hider pin/weld
14.5" FN button rifled, chrome lined barrel
PRI gas block
BRT gas tube
LMT enhanced BCG
H2 buffer and carbine spring

I will also be using a PRI gas buster charging handle and SF M85 rail. Though not "functional" pieces, they do affect performance. I have found the gas buster to be effective on my other guns, and I like the low profile of the SF rails on my other guns. The use of this rail doesn't free float the barrel but, for my application, I have found accuracy more than acceptable, with my carbine gas guns, utilizing the M73 rail.

It'll all be on a MARS lower with a Specter on top. Cautiously optimistic.

Can arrived at LGS today. Pretty light, considering it's length. The reflex portion is not as long as I imagined. I'd say you get between two and three more baffles worth of internal volume out of the aft portion of the silencer. I did change my mind to a brake, as opposed to the Vortex mount. The brake likely serves to encourage gas flow into the rear section of the can, where the hider wouldn't. My preference always dictates a hider, but, this gun being permanently suppressed, combined with the symbiotic relationship of brake and can, I opted to use the brake.

The OCM5 sounds interesting. My AEM5 was recently let out of jail, still haven’t fired it, but the first thing I noticed was it’s a pig, considering it’s not really QD. No big deal as I’m not huffing it through the mountains. Had the OE been available when I purchased the AE, I might have considered it, despite the higher cost of the OE for the little bit of weight savings.

The OCM5 is 15.93oz, according to my scale.

On paper, my AEM5 is 21oz. I’ll have to weigh it later. So at just over $100 to save 4oz may be worth it. The AE is essentially a clone, for better or worse, while the OC is the upgrade. Weight and blowback being considered.

Edited to correct: on my kitchen scale it weighed 19.8oz. Take it with a grain of salt.

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

16.02 is the weight of the OCM5, according to the manufacturer. Maybe they err on the side of caution.

I have an OPS 12th in 30. Its heavy but the tone is fantastic and it quiets my SCAR down quite nicely. It also has very low poi shift. The mounts can be a bit of a PITA. I suggest getting a one piece reflex brake that has the integral collar. Also some of the muzzle devices are long enough to pin and weld on a 14.5. In summary great, crazy durable can for what it is nd when I bought it. I am looking for a can with swappable end caps to run 556 which it does fine with but isn't incredible due to the wider bore.

I got the gun together. Was able to put one mag through it so far. May be a bit more gas in the face than anticipated. I am hoping it will be reduced a little bit when I install the H2 buffer that I thought was already in the lower (turns out it had an H in it). Hard to judge the effectiveness of the can, when it comes to sound reduction, without having some side-by-side comparisons standing by. I know it didn't hurt my ears without ear protection (I know it actually does hurt my ears). It is refreshing to hear the round hit the steel with a bit more authority; the longest AR I've messed with in the last while is 11.5". Initial impressions are telling me the OpsINC-style cans really aren't worth the...Length? Weight? Price? I formed those as questions because the OCM5 doesn't add any OAL that wouldn't be there with a conventional can; nor weight; and it isn't exceptionally expensive. So, I dunno. One could argue that the weight is close to something like RC2, which has much more to offer, when it comes to hard use performance. So, the weight is arguably a con. The gun is certainly longer than my current go-to, but my attitude has shifted in favor of ballistic performance of late, so that's a compromise I am willing to make. It's certainly quieter too. Unfortunately, I have no comparable builds that can host other cans, to enable a side-by-side comparison, to gauge sound reduction performance. Another potential con is the lack of a latch in the silencer attachment method. This design doesn't have a self-tightening aspect, like an OSS, so I feel persistent tightness checking is necessary. I may create and test a crude redundant stop of sorts. As a tangent to the Colt 6940 thread, concerning length of the handguard: it is refreshing to have a smidge more space, with the drop-in mid length rail. I am able to use a Unity TAPS switch for my light and laser, which has been neglected in a drawer for months, because it wouldn't fit on my other carbines. I'll update this thread, as I get more time behind the gun. I am going to try to shoot a few rounds with the H2 today. I am considering the build a sort of "compact recce" or "recce carbine", as opposed to recce rifle. It was built to potentially take over as my go-to general purpose carbine though. If the Marines in Fallujah managed to whoop ass in buildings with M16s, I can likely make due with a suppressed 14.5".

Fired a few more diagnostic rounds this morning. I opted for BRT's recommendation, on the gas port, based on my rifle's specs. The gun will be suppressed all the time. Based on the mild gas irritation I experienced, in my initial firing of the setup, I suspected I may be able to go a bit smaller on the port. I could, but I don't think I will. I ran three rounds each of M193 and M855 without the silencer this morning, the idea being that, if it functioned without the can, I could certainly go smaller on the porting. It did function, but only just. It will cycle both rounds, but will not lock back on empty. Considering my practical mindset behind the build, I am going to leave it with the .070" they sent. If my silencer were to experience a catastrophic event, I can still employ the weapon to some degree of efficacy. I suspect that, if I swapped the LMT carrier out for a regular one, the gun would lock back on empty without a can. So, for this particular gun, I'll opt for a perhaps slightly over-gassed condition in it's intended configuration, in the name of extreme reliability with the can, and worst-case performance ability without it.

After some more time behind the gun, I don't think the lack of a latch mechanism on the silencer is anything to worry about. It seems the taper surfaces hold it pretty solidly; I have yet to have it loosen up on me. As mentioned in the flash signature thread, this setup has very good flash performance, which is a happy accident. I have yet to get the gun properly zeroed, as I had to switch to a different rear iron sight, after encountering interference with my night-time optics setup. I hope to square away the zero, and shoot for accuracy, sometime in the next week or so. The first time I set out to zero the gun, I noted some odd fliers (one out of a five shot group). I hope this was a result of poor performance on my part; we'll see.

The gun has gone through some changes. After noting some signs of undergassing, I opted to install a regular mid gas tube, along with an adjustable carrier. All the important operational bits are now as follows:
LMT recoil spring (stouter than all my other springs by 9oz, according to my measurement setup)
H2 buffer
Bootleg carrier backed-off one click from full gas
14.5 mid barrel using regular mid gas tube
Otter Creek OCM5 silencer

Ejects consistently at 4o'clock, with zero hiccups since reconfiguring. I did square-away the zero on the gun, and got zero data for the night optic. Have yet to group it for accuracy. I hope to do that with this, and one other gun, today. I also want to do some kind of blind sound test of my three ARs. I am curious how the different barrel lengths, gas systems, and silencers sound:
11.5"/carbine/GMT HALO
14.5"/mid/OCM5
16"/rifle/TREK-T
All use vented carriers, with the 14.5 venting the least.

In shooting this gun and one other, yesterday morning, while comparing their respective optics, I had a favorable experience, which I didn't acknowledge until thinking back on it today. Both guns were very pleasant, in terms of their silencer-induced gassiness. It is, to a point, dependent on atmospherics, and yesterday was chilly and still. In thinking back on the expereince, I realized I didn't notice anything at all. Pretty good, as I ran both guns through a rapid-fire 12-shot drill, which is typically more than enough to sting the eyes. The setups are as follows, for anyone interested, shooting 55gr XTAC:

14.5" mid-length gas barrel
Otter Creek OCM5 silencer
regular gas tube in regular block
Bootleg carrier backed-off one click from full gas
H2 buffer
LMT carbine spring, which is stouter than a regular carbine spring; maybe similar to Sprinco blue

16" rifle-length gas barrel
Gemtech Trek-T silencer
regular gas tube in regular block
GI carrier with .090" vent
H3 buffer
regular carbine spring

I have since done more shooting with the OCM5. I think I can say, with confidence, that it is not a particularly quiet can. This sucks, because the reason I bought it is because the AEM5 is often cited as an exceptionally quiet can, and the OCM5 has had similar reviews.

In some shooting I did yesterday, I ended up with a good comparison circumstance: I ran the same course of fire, with the same cadre, twice; once with a 10" with Griffin M4SDK, and again with the 14.5" with the OCM5; both on the same lower/recoil setup of H3 with Sprinco red. I didn't set out to perform any sound evaluation, so I wasn't necessarily paying it any attention; I was focused on performing the lane. After I completed that second run, the cadre said, "that gun is way louder than your other one"; I took that brief moment to consider it as well, and agreed with him. That says something: the fact that the comment was inspired by the perception of sound even outside the context of a critical sound comparison; also that the OCM5 had 4.5" more barrel to burn powder, and has a larger internal volume.

I had previously noted it's exceptional flash performance, and I am sure it performs in the context of precision and repeatability, by design. On this day, under these comparative circumstances, however, it's sound performance was less than impressive.

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

If you had to do it all over again do you think you would go with a lighter, less "gimmicky" silencer, even if it added more to OAL?

Or might you have accepted a certain amount of noise, and gone for a shorty, again, non-reflex design?

I do appreciate you sharing these experiences, I find the gas system tradeoffs and performance compromises interesting. Lots to geek out on here.

I don't think I'd put the OCM5 in the "gimmicky" category, considering it's a copy of a proven silencer issued early in the GWOT. Also, it doesn't actually have any kind of OAL advantage; using a SOCOM RC2 as a benchmark, it actually adds more to the OAL.

I do recall favorable impressions of the silencer, and said as much in comments above, but it seemed so stark the other day. One thing that could be a factor is my use of a flash hider mount; though this is only speculative. I made mention in a past comment, that I opted to use a brake, instead of a hider. I actually did end up using a hider, as the guy that was pinning and welding the device wouldn't perform the work "through" threads. The Vortex hider has flats that interrupt the external threads, where the brakes don't; so he wouldn't P/W the brake. As speculated in that previous post, I think the brake may serve to encourage gas flow into the aft portion of the silencer, where the hider may be short-changing that performance aspect.

I suspect my shooting with the OCM5 will be somewhat limited, for the foreseeable future. A friend has a DD MK12, and he showed interest in the OCM5. I told him to get a brake and collar, and he's welcome to use it whenever we're shooting together. So maybe he'll get some use out of it. As for me, the only upper I have equipped for it has a 14.5" barrel, which is longer than I care to mess with right now, especially if sound performance is noticeably worse, compared to a shorter rifle/can.