In this Field Test Shooting video for the Umarex Marlin Old West CO2 BB Revolver I check real-world performance: first I measure fps using a fresh standard 12-gram CO2 cartridge and 4.5 mm steel BBs through my chronograph. After that I hang a paper target at 30 feet and fire 10 rounds using the Single-Action-Only trigger to see what kind of grouping the revolver delivers straight out of the box. If you haven’t already seen my Tabletop Video Review for the John Wayne Marshal CO2 BB Revolver, watch that for full specs and close-up footage.
For the velocity test I put five shots through the chronograph. The slowest registered 345 fps and the fastest hit 416 fps, with an average of 403 fps, right in line with Umarex’s claimed 400 fps. Perfect for popping cans and casual plinking out to roughly 30–40 feet. The test was done inside a sea can at about 18°C (≈64°F), which gives a middle-of-the-road CO2 performance; warmer weather will typically push velocities higher.
Next I set the paper target on my pellet trap at 30 feet. Using my usual semi-rested position (hands braced on a front sandbag and seated on a stool), I fired 10 rounds with the Marlin Old West. The group measured roughly 4 inches, a bit left and just slightly high from the bullseye — not far off and similar to the grouping I got with the John Wayne Marshal CO2 BB Revolver, although the Marlin’s velocity numbers were notably higher.
The Umarex Marlin Old West CO2 BB Revolver is an inexpensive, mostly-plastic Single Action Army style revolver. There’s a fair amount of polymer in the construction, but it still feels solid despite being on the lighter side. That lighter weight can make the gun feel a bit twitchy in the hand compared with heavier replicas, which can affect accuracy. At the time of this video the Canadian price was about $99, which makes it good value — especially since it loads 18 rounds quickly compared with traditional shell-loading revolvers, meaning more trigger time with less fuss. There are a number of similar replica revolvers available from our Replica Airguns stores in Canada and the US, so check our stock if you’re shopping around.
Type: BB Pistol. Manufacturer: Distributed by Umarex Model: Marlin Old West Revolver Materials: Mostly plastic, some internal metal parts. Weight: 1.2 pound (544 grams). Total Length: 10.5 inches (26.6cm). Barrel: 5.5 inches 14cm) metal non-rifled. Propulsion: CO2. Action: Revolver SAO. Ammunition Type: 4.5mm Steel BB’s. Ammunition Capacity: 18 round internal magazine. FPS: Claimed 400.
Trigger Pull: The trigger on the Umarex Marlin Old West CO2 BB Revolver is single-action-only, so you must cock the hammer before each shot. That removes most of the trigger travel and effort, giving the Marshal a short, light, and easy-to-manage pull. It’s ideal for deliberate, accurate shooting, but less suited to action-style rapid fire unless you’ve got a very fast thumb.
Accuracy: I haven’t tested the Marlin Old West model specifically, but it should perform very similarly to the John Wayne Marshal CO2 BB revolver, they’re nearly identical aside from licensing, safety, and magazine placement. In my field test of the John Wayne Marshal it averaged closer to 360 fps rather than the claimed 420 fps and produced roughly a 4-inch, 10-shot group at 30 feet. You can watch that video here; I’ll hope to be posting a dedicated field test for the Umarex Marlin Old West soon.
Build Quality: There’s not a lot to get excited about in terms of materials, the Umarex Marlin Old West CO2 BB Revolver is mostly plastic with some internal metal parts like the barrel, trigger, hammer, and CO2 components. It follows the common two-half, screwed-together budget construction, which looks cleaner on the side where the screws are hidden. At just over a pound it’s fairly light. With relatively few moving parts, it should be reasonably reliable; the mechanical components do what they need to do and feel suitably solid for the price.
Realism: At first glance the John Wayne Marshal CO2 BB revolver resembles a Colt Single Action Army Revolver in shape and size, but it’s much lighter, about half the weight. The lack of real bullet openings in the cylinder (when viewed from the front) reduces realism. I’m used to the newer generation of revolvers with working cylinders and loadable, removable shells; those are pricier and hold fewer rounds, but they offer a much more authentic experience.
Pros:
A decent looking replica of a Colt Single Action Army Revolver.
Single action only trigger is short and light and well suited to careful shot placement shooting.
400 claimed fps is about perfect for plinking at ranges up 30-40 feet.
18 round magazine has a nice high capacity and easy to load when empty.
Should get lots of shots per CO2.
Safety is well hidden underneath just in front of the trigger guard.
I like the look with the all black receiver and simulated wood grips.
CO2 Allen key is built into grip so always have it on hand and will not lose it.
Marlin licensed and seems to be $50 less than the almost exact same John Wayne version.
Cons:
Mostly plastic builds makes it a bit light in the hand.
No fake shell holes in the front of the cylinder, could have added this for a more genuine look.
Not a big fan of the clamshell plastic packaging.
Comments: The Umarex Marlin Old West CO2 BB Revolver is a solid choice if you want an old-west single-action cowboy BB shooter for less than the nearly identical John Wayne Marshal (it’s about $50 cheaper). If you want more authenticity, consider one of the shell-loading Single Action Army style revolvers, they cost more, shoot a bit slower, and carry fewer rounds, but they deliver a much higher level of realism.
Yet another Mystery box with good stuff inside for me to discover and checkout and share with everyone! In this Replica Airguns August 2025 Mystery Box Video I reviewed three products from Umarex, and all of them are some sort of BB gun related product, one pistol, one revolver and one rifle and interestingly not all are CO2, as one is AEG powered which is more or less a new thing with steel BB guns. Barra introduced their 400e AEG AR Steel BB Rifle a while back and now Umarex has their own version of a similar AEG BB rifle in a sightly more true AR platform called the Umarex AER16.
The Umarex Marlin CO2 BB Revolver is really just a Marline licensed version of their Marshal CO2 BB Revolver but it us $50 less so unless you really want the Marshal licensing then go for the newer Marline version. Another Umarex product out of this months Mystery Box was the Umarex DS11 1911 NBB CO2 BB Pistol which is a pretty basic almost all plastic NBB CO2 BB Tactical 1911 that uses the standard metal BB Stick magazines. It does however look a lot better than most of these simple NBB Plastic BB Pistols on the market so in terms of looks it has that going for it for sure.
