...with my OCM5 and a Midwest Industries SP handguard.

I have been using a KAK handguard that stops just short of the rear of the can. It's been a good setup: solid, slim, aesthetically pleasing, etc. However, I'd like to get my light out further, and make room for a front sight. Also, the slim nature of the KAK, and presumably others like it, makes for hot spots around the chamber and gas block. After a couple mags worth of moderately-paced fire, you better have some gloves on.

In doing some night shooting a week or so ago, I noticed (visually, thanks to the IR spectrum) the aft portion of the OCM5 doesn't heat up like the baffled portion. That being said, I feel like I might be able to get away with tucking it. The general consensus on tucking is it's a no-go due to heat. Considering my current heat issue untucked, and the visual observations of the OCM5, I think it's worth a shot.

I got the 15" handguard. I sent it away to have a portion of it cut away. It will end up surrounding the aft 1/3 portion of the can, with a portion of the top rail remaining, running out over the next 1/3 of the can. That extra rail will let my push my light out, and give me room for a front sight, ahead of my light/laser switches.

I am almost certain the chamber and gas block areas will run noticeably cooler. Whether the portion surrounding the rear of the silencer stays manageable remains to be seen. If it gets no hotter no quicker than the gas block and chamber did, with the KAK setup, I'll call it a win.

Seems like a sensible thing to do. The more I shoot with my cans the less I want to touch them. Or be able to touch them inadvertently, rather.

If there's an airgap you shouldn't be able to cook your WML, but maybe that's just a fun wager.

I am not going to have the WML tucked super close to the can, so I think it should be OK. I have definitely considered that as a point of concern though.

My effort is being made not so much in the name of shielding the can from inadvertent contact, than it is in the name of gaining top rail length and a bit more grip length. Based on my research, I think this silencer (and others like it) is the only one that the tuck job is potentially agreeable with. Folks say that tucking a conventional can isn't ideal, because the blast chamber area, which is the aft portion in a conventional silencer, gets hot quick. The reflex style of the OCM5 has that rear portion running a bit cooler.

This is all speculation, at this point. Two or three mags worth of some quick-cadence practice will be all that's needed to see if it's viable. I hope it is.

I'm going to make a comparison. It's entirely anecdotal, based on third-hand observation of non-scientific testing. It's also relating another platform in a pistol caliber and introducing a third subset of suppressor categories, but I'm going to make the comparison anyway.

There's two suppressor choices for the Scorpion that I was looking at: The Innovative Arms SC-9, and the Ratworx Venom. The SC-9 is a true integral can, and the Ratworx looks like an integral, but it's a reflex can. They both have integral handguards.

Now, the SC-9 is much quieter than the Venom and does the 115gr ball ammo subsonic at the muzzle thing, and the Venom does not. However, the difference is, the SC-9 is know for getting stupid hot, and the Venom, a reflex design, almost can't be shot at a firing schedule that gets it too hot to hold. I wound up going with neither, but I still wonder about the Venom and dinking around with radially porting the barrel so that it does behave as an integral, but I digress.

Both Ratworx and AB Suppressors (who do mostly or all reflex designs) flat out say the reason it doesn't get as hot is because it's a reflex can, which does two things:
1 - Gives the gas more room to expand, which cools it better before the projectile exits, so it's quieter.
2 - The added exterior volume allows for more even, and quicker heat dissipation.

So, those same principals applied to the OCM5, I could see potential for it working as a nested/tucked setup. I wonder about getting your hand that far forward, but I don't think you're going to cook your light and laser over the course of a few magazines fired at a rapid pace. Again, I don't know much, but I have a very vivid imagination.

I have a friend who is a huge Mk12 and AEM5 fanboy I was going to run this setup past until I realized he has zero experience with any other cans, or any other setup besides an AEM5 on a Mk12, and thus, would have about nothing to offer the conversation. I'm not sure he's ever shot it fast enough to get it smoking, now that I think back on our conversations.

IMG_8966 by Michael Rose, on Flickr
IMG_8967 by Michael Rose, on Flickr


Two of my tuck jobs with a Wise Man Hot Pocket. No issues with the light or heat to my hand. I have not done any mag dumps though.

Got mine put together. I hope to zero in the next couple days, and do some shooting with it on Sunday. Other than the handguard, the gun is exactly the same as it has been. I was able to get my light, light/laser buttons, and hand out a little further. That combined with (hopefully) better heat characteristics should make it worthwhile. It's possible the heat will be worse though. You don't know till you try.

Also, this configuration allows space for a front BUIS, which is excellent. The prior setup was my first-ever rifle without BUIS of any kind. I had zeroed a set, and kept them in my equipment, but they wouldn't fit on the rifle. I still don't have a rear one, if I want to be able to use the Elcan, among my other optics, but at least I don't need to install both of them, if they're required.

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

Well... That's a big ol' no-go. Even only tucking the reflex portion of the OCM5, the handguard gets stupid hot.

I fired ninety rounds at a moderate pace, through various practice drills. The only thing that came close to "mag dumping" was the 12-shot rapid fire target transition drill. I performed that drill three times, intermittently across that ninety rounds.

I was surprised that the chamber and gas block areas of the handguard still got silly hot. The MI "SP" handguard is large, has MLOK all the way around, and has a chunky well-vented barrel nut. Perhaps the high backpressure nature of the OCM5 puts more heat in the chamber than another can would.

Of course the portion of the handguard surrounding the aft portion of the silencer got stupid hot too.

My flashlight and laser were scalding. I couldn't keep a finger on either for more than a second. Luckily they both still functioned fine afterward.

Long-story-short: Tucking is a bad idea, even if it's only the back end of a reflex can. If the rifle is intended to be a "fighting rifle", that silencer needs to breathe. My setup before this experiment got hot around the chamber and gas block, and of course had a hot silencer. This tuck job made those handguard portions even hotter, added a third portion, and of course retained the scorching silencer. Better to have only one part (the silencer) to be wary of, than the whole darn front end of the rifle. Not to mention the potential for accessory damage due to heat soak.