Gemtech's New Lunar 9 Suppressor: Full Review

You want it all? Consider it done.

August 12, 2025 By Patrick Sweeney

What do you want out of a pistol suppressor? Light weight? Modularity? Adaptable to many calibers? Easily mounted on various hosts? Quiet? Not expensive? With the Gemtech Lunar 9 the answers are; Yes, yes, yes, yes, yes and yes.

The Lunar 9 is a pistol suppressor meant, obviously, for use with 9mm firearms. To makes it lightweight, Gemtech makes almost all of it out of aluminum. The first baffle, the blast baffle, is 17-4 stainless, but the rest of the baffles are aluminum. (The Lunar 9 is a departure from the Gemtech G-Core monocore design.) The baffles also have a notched entry port, there to induce turbulence and decrease sound. The two external tubes are aluminum, as are the front cap and most of the rear cap assembly. All this aluminum is Type III hardcoat anodized, so it is tough. To make the Lunar 9 durable, the threads are an insert in the rear cap and the threaded portion is made of stainless steel.

Lunar 9 Suppressor — The Gemtech Lunar 9 fully assembled is ten ounces. Any lighter and you wouldn’t need the booster. (Photo provided by author.)

So, full-up the Lunar 9 is about ten ounces. Full up? Yes, because the Lunar 9 is made as two assemblies. The two halves can be unscrewed and the front cap swapped from the front section and re-installed on the rear section. Oh, notice the shape of the front cap clearance hole? Yes, that is a square 3⁄8" hole, the same size as your ratchet wrench. If you don’t clean your Lunar 9 often enough, and thus carbon-weld the cap on, you can use a ratchet wrench to remove it. (Tsk, tsk.) With the front cap installed on the rear section, you now have a compact 9mm suppressor that tips the scales at about seven ounces.

Why? Because the Lunar 9 can be used on more than just pistols. With a PCC and its longer barrel, you don’t need the fully assembled Lunar 9 to be quiet, so the rear half makes your PCC very quiet and doesn’t add a lot of length or weight. You can even put the Lunar 9 on a rimfire. Granted, the axial clearance in the bore of the Lunar 9, made for a 9mm bullet, will be greater than on a rimfire suppressor. That means that theoretically it won’t be as quiet. But you’re getting most of the rimfire suppressor quietness without the cost and paperwork of an extra suppressor.

Disassembled Lunar 9 — The Lunar 9 disassembled. The baffle that looks different is the blast baffle, and it is made of 17-4 stainless. So is the piston. Everything else is anodized aluminum. (Photo provided by author.)

To that end, and to accommodate the various calibers and mounting systems, the Lunar 9 can be had with a veritable basket of rear caps. On hand, I have the standard booster cap, for use on pistols. This L.I.D. keeps the extra weight of the Lunar 9 from “stalling” the cycle of your pistol. By storing some of the energy and then feeding it back into the system, it boosts the slide to function. I’ve mentioned this before but the effect is to make it feel as if the pistol is recoiling harder than without the suppressor. It is a small thing and you’ll soon not notice it.

For the firearms that don’t need a booster, Gemtech also offers direct-thread rear caps in all the various sizes: ½-28, ½-32 and ½-36. You’ll need the “28” for your rimfire firearms. (Just don’t use it to mount the Lunar 9 on a 5.56, that would be bad) On a .300 Blackout with subsonic ammunition only, you’ll need a 5⁄8-24 direct-thread cap. Yes, .300 Blackout subsonic, as long as the barrel is eight inches or longer. The “32” and the “36” are for 9mm pistol-caliber carbines with those thread pitches. The ½-28 is a lot more common now, but back in the old days there were a lot of PCCs made with the 32 or 36 thread pitch (I’m looking at
you, Colt.)

Lunar 9 disassembled — The Lunar 9 can be had with many different rear caps (or even all of them) to let you mount it on almost anything. The row of direct-thread caps covers a lot of bases, and the booster and the HK three-lug add in a bunch more. (Photo provided by author.)

For those who have an HK, or something, made to use the mount, Gemtech even makes a rear cap that fits the Lunar 9 onto an HK three-lug mount. If you don’t have an HK, but want to three-lug it in style, Gemtech even offers an adapter to convert your threaded muzzle to HK three-lug so you can then use the three-lug rear cap for a QD mount setup.

Back to the modularity for a moment. The front cap of the Lunar 9 fits onto the front of the front section and also the front of the rear section. The threads of the two sections are proportioned such that if you happen to install the baffle stack incorrectly, the front cap won’t tighten down flush with the tube. That’s your clue that you somehow did something wrong. Gemtech has gone to a lot of trouble to make it as easy as possible, and as easily-cleaned as possible.

Lunar baffle — Each baffle is also notched on the entry port, to induce turbulence and thus make it quieter. (Photo provided by author.)

The baffles are stepped so they snap together. They are also notched and lugged so they will only assemble in the proper orientation. If you don’t get the notch and lugs lined up, the stack will not let you screw the cap on. The stepped baffles also provide more of a seal to the tube than regular “K” baffles do, so it is easier to disassemble and clean.

The booster assembly also has an interesting detail. Instead of adding more complex machining to lock the aluminum body to the steel threads and piston lugs, Gemtech simply installed a stainless steel setscrew. The purpose of the lugs on the piston are to let you shift the point of impact if you need to. If you find the POI is off of your sights, simply grab the Lunar 9 body and pull it forward on the barrel. Give it a slight rotation and ease it back. You are now locked into a different slot of the lugged piston. Try again. One of the lugs will get you dead-on, or close enough. Fair warning: that setting is just for that pistol. Swap the Lunar 9 to another pistol and it might require a different setting. That’s how they all work, nothing personal about the Lunar 9 in that regard.

Booster and cap — The booster rear cap assembly with its body, piston, spring and mount cap. (Photo provided by author.)

How quiet is it? The measured reports indicate that a subsonic 9mm load with the full length of the Lunar 9 puts it in the low 120s, decibel-wise. That is low enough that even I, Mr. Always-Hearing-Protected feel comfortable shooting without muffs or plugs. The full length on a PCC carbine is giggle-worthy. Assembled short the Lunar 9 makes everything subsonic quiet enough that you can shrug off periods of shooting. The supersonic loads all will have the “crack” with them, and if you are shooting steel the impact on steel will be perceived as a lot louder and sharper than the muzzle report. The short answer: the Lunar 9 is amazingly quiet.

I tested it on a CZ P-09 C, and the pair never failed to perform. It also hit to the sights without having to adjust the piston-lug location, so I got lucky there. Which seems to happen often with modern suppressors.

Oh, and is it full-auto rated? Yes, kinda. If you limit yourself to bursts of four to eight rounds, at four- to eight-second intervals, your Lunar 9 will be just fine with that. That’s in 9mm, of course. I suspect that if you are using it on a rimfire there’s no limit. And if you are using a .300 Blackout subsonic, you’d be best off staying more in the four-round-burst schedule than the eight-round one.

You get all this goodness for a list price that is mid-six hundreds. Actual over-the-counter price will be less,
of course. A one-word summary: “Murica!”