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Education / Training Gamo Swarm Fusion 10X Gen II air rifle: Part 3

Gamo Swarm Fusion 10X Gen II air rifle: Part 3

by Tom Gaylord
Writing as B.B. Pelletier

Gamo Swarm Fusion
Gamo Swarm Fusion 10X repeating rifle.

Part 1
Part 2

This report covers:

  • Today’s test
  • The test
  • Trigger adjustment
  • Sight-in
  • Air Arms Falcon
  • H&N Match Green
  • Gamo Master Point
  • RWS R10 Pistol
  • Firing behavior
  • JSB Exact 8.44-grain domes
  • H&N Baracuda Green
  • JSB Exact Heavy
  • JSB Exact RS
  • Firing behavior
  • Whew!
  • 10-shot group with Match Green
  • Conclusion?
  • Summary

Today we start looking at the accuracy of the Gamo Swarm Fusion 10X Gen II repeating breakbarrel spring-piston air rifle. I’m hoping for a great result!

Today’s test

The Swarm Fusion has open sights, and I’m testing them today. It also comes bundled with a scope that I will test in another report. Since this is the first accuracy test, I decided to just shoot 5-shot groups so I could test lots of different pellets. Let’s get started.

The test

I shot off a sandbag rest at 10 meters. I used a modified artillery hold, because the thumbhole stock on this rifle doesn’t permit a classic hold. The only difference is I did grasp the pistol grip.

I rested the rifle on the flat of my open palm with the heel of my hand back by the triggerguard. A rifle that recoils like this cannot rest directly on a bag or anything else!

I made no attempt to adjust the sights throughout the test until the very end. So, after sight-in the pellets went where they wanted to.

Trigger adjustment

I told you in Part 2 that I would buy a long-bladed small Phillips screwdriver to adjust the stage two trigger pull. After I had placed the order, reader New To Old Guns told me the second stage is already adjusted as short as it can be. Nevertheless, when the screwdriver arrived I tried adjusting it.

Gamo Swarm Fusion trigger
Don’t bother trying to adjust the second stage of the trigger. I did and there was no change.

NTOG was right, there isn’t anything you can do to the second stage. I adjusted it several times and found no difference. Well, at least I now own a nice set of long-bladed screwdrivers!


Since I was shooting with the installed open sights I started shooting at 10 meters. The first shot went high and I discovered the rear sight was adjusted up quite far. That was something I’m sure I did when examining the rifle. I adjusted it down and was on target in three shots.

Air Arms Falcon

The first pellet was the Air Arms Falcon. Four went into a tight 0.245-inches, but the fifth pellet opened it to 0.656-inches between centers at 10 meters. Maybe this pellet is worth further exploration.

Swarm Fusion Falcon group
Air Arms Falcons were tantalizing. Four are in 0.245-inches, but the fifth shot opened it to 0.656-inches at 10 meters.

H&N Match Green

Next up were H&N Match Green pellets. Every one of the five shots broke the sound barrier with a loud crack. But they were accurate! Five made a group that measures 0.341-inches between centers.

Swarm Fusion Match Green group
The Swarm Fusion sent 5 H&N Match Green pellets into a 0.341-inch group at 10 meters.

Gamo Master Point

I tried five Gamo Master Point pellets next. Four went into a nice 0.519-inch group at 10 meters, but the fifth shot opened it to 1.19-inches.

Swarm Fusion Master Point group
Four Gamo Master points went into a nice 0.519-inch group, but the fifth shot opened the group to 1.19-inches at 10 meters.

When something like this happens while I’m shooting with open sights I wonder if it was me that threw the shot. The other thing I wonder is if there is a bad chamber alignment in the mag that causes one shot to go wild like this.

RWS R10 Pistol

Next I loaded 5 RWS R10 Match Pistol pellets into the Fusion magazine. They went into 0.519-inches at 10m meters. Another good group!

Swarm Fusion R10 Match Pistol group
Five RWS R10 Match Pistol pellets went into 0.519-inches at 10 meters.

Firing behavior

At this point I will tell you that the Swarm Fusion does slap me in the face just a little when it fires. It’s not much but I can feel it. I will also tell you that the trigger now acts very much like a light single-stage trigger. It’s easy to use but the let-off point is vague.

I’m not telling you this to discourage you. This rifle seems to be a winner in most respects. You just need to know what you are getting.

JSB Exact 8.44-grain domes

The next pellet I tried was the JSB Exact 8.44-grain dome. The Fusion 10X put five of them in 0.889-inches at 10 meters. This is perhaps not the pellet for the Swarm Fusion.

Swarm Fusion JSB Exact group
At 10 meters the Gamo Swarm Fusion put 5 JSB Exact 8.44-grain domes into a group that measures 0.889-inches between centers.

H&N Baracuda Green

The next pellet I tried was the 6.48-grain H&N Baracuda Green. They did not go supersonic, thankfully. Five went into a 0.708-inch group at 10 meters.

Swarm Fusion Baracuda Green group
The Fusion put 5 H&N Baracuda Green pellets into a 0.708-inch group at 10 meters.

JSB Exact Heavy

The next pellet I tested was the JSB Exact Heavy dome. The Swarm Fusion put 5 of them into exactly 0.40-inches at 10 meters. That is a nice result!

Swarm Fusion JSB Exact Heavy group
Five JSB Exact Heavy pellets went into 0.40-inches at 10 meters.

JSB Exact RS

The final pellet I tested was the JSB Exact RS dome. These are sometimes surprisingly accurate. But in the Fusion I had four that were close and one that was a flier. Four are in 0.472-inches, with five in 0.881-inches.

Swarm Fusion JSB RS group
Five JSB Exact RS pellets went into 0.881-inches at 10 meters.


That’s 8 pellets tested in the Gamo Swarm Fusion 10X rifle. There was never a bobble in feeding the pellets, so that magazine works quite well. Of course today was shot with open sights and there is a scope test coming, so we are not finished with the Fusion. However, I did want to shoot a 10-shot group with the most accurate pellet which turned out to be the H&N Match Green pellets. That’s too bad for a couple reasons. One, they are wadcutters and probably won’t hold up at 25 yards. And two, they are supersonic and very loud to shoot. But they were the best so I picked them.

Looking at where they hit the target I adjusted the rear sight for them. I went two clicks to the left and three clicks up.

10-shot group with Match Green

Ten H&N Match Green pellets went into 0.739-inches at 10 meters. Since open sights were used, that is a terrific result! The sight adjustment didn’t move the group very much.

Swarm Fusion 10Match Green group
Ten H&N Match Green pellets went into 0.739-inches at 10 meters.


This is an accurate air rifle. It’s a little harder to cock than an Umarex Synergis underlever repeater, and of course it costs more, but if you want power in a repeating breakbarrel, this is one to consider.

I will pare down the pellets I test at 25 yards, and I will also test 10 through the mag against the same 10 loaded singly. They still have to be loaded through the mag, but the same chamber is used every time.


We are not finished with the Fusion just yet. I still have to mount the scope and move back to 25 yards. Stay tuned!

author avatar
Tom Gaylord (B.B. Pelletier)
Tom Gaylord, also known as B.B. Pelletier, provides expert insights to airgunners all over the world on behalf of Pyramyd AIR. He has earned the title The Godfather of Airguns™ for his contributions to the industry, spending many years with AirForce Airguns and starting magazines dedicated to the sport such as Airgun Illustrated.

40 thoughts on “Gamo Swarm Fusion 10X Gen II air rifle: Part 3”

  1. B.B.,

    I vote for the Air Arms Falcon for the 25 yard test, although you may to first determine if flier you experienced was due to a chamber or the sights.


    PS The first picture is mislabeled as the FX Dreamlite precharged pneumatic rifle.

  2. It seems to me that in every group there a consistent flier. Are we certain about the magazine? In any case I think that you have higher standards for calling a rifle accurate.

  3. A question..
    Are you loading 10 pellets in the mag?
    5 of one pellet, and then 5 of another pellet in the next 5 slots in the mag?

    If so, I would mark chamber #5.

    If not, I Would look and FEEL for burs in the movement of the mag.

    Since it seems to be the fifth shot, something is consistently not aligning correctly.

    Also, the consistent shooters seem to be either wadcutter pellets, or low domes.

    Could the pellets be getting knocked around in the mag during the recoil, and number 5 being clipped as it loads?

    I have seen heavy recoiling African game rifles have issues with the bottom round in the magazine having the bullet either backing out of the case during the recoil of the 4 shots above it, or being driven into the case and not wanting to feed due to the now incorrect overall cartridge length..

    I know pellets are not cartridges, but if chamber 5 is too loose, it may allow the pellet to become damaged, or get mis aligned.


    (Self confessed addict of anything with a trigger.)

    • Ian,

      I loaded it that way most of the time but not all the time. That’s why I plan to test it for the magazine next time.

      I said it was the fifth shot but since I wasn’t watching through a scope it could have been any of them other than the first shot that I checked through a spotting scope.


  4. BB,

    I still can not get past that contraption on the top,…. despite it being an engineering marvel. Conversely, that may be an attraction to some.

    Looking forwards to more distance and scoping. Suggestion, shoot it sandbag rested at the front, with no hand under,… just to see what happens.

    Good Day to you and to all,……… Chris

    • Chris,

      That thing sure is b’ugly, from the wart on her nose to the droop of her derrière. I like mine long and slim and tight. The Synergis is a more attractive way to do it. Of course beauty is in the eye of the beholder.

        • Chris,

          “Of course beauty is in the eye of the beholder.”

          For me, the loading mechanism is the best looking part. She has a long, bulbous nose with a glowy wart on top of it and her belly hangs way down. I personally would be ashamed to be seen with that in my hands. 😉

      • Geo,

        Saved to “bookmarks”,…. 😉 ,……. and a hand written note to remind me that I saved it! 🙂 Will check out this weekend. GF1 likes them, so maybe they will be better than the JSB’s that I am using now.

        Thanks,……. Chris

  5. BB,

    Warning to everyone. These are my thoughts. These are my concerns. If they interest you, fine. If not, get your own.

    I cannot remember if you told us, but will this mechansim fit on the Maxxim? This mechanism does provide a smoother look than the previous one, but I would just as soon remove the glowy thingy sights. Is the front sight easily removable?

    I also have a concern with all of that motion. The more parts, which are probably polymer, the chance of some part failing. Then there is the issue of proper alignment. Once again, more places for an issue to arise.

    • RR,

      No. This mechanism is unique to the Fusion.

      As far as longevity goes, you may be right. I’m still in favor of single shots for that reason and many others. But some folks have trouble loading them and this rifle seems to be a good solution to that


      • B.B.,
        in line with the thoughts expressed here on the repeating mechanism, I am intrigued by the performance of this rifle, so far, and my question is this: “Do they make a version of this rifle (same gas piston, same long power stroke) without the repeating mechanism?”
        Because, like you, I favor single shots, although I do have issues with loading sometimes, so I bought some of those pellet pens from PA…and they really do help! =>
        Thank you, take care,

      • BB,

        I myself am a single shot kinda guy. A bit of info for those who may be concerned with the mechanism breaking, it can be somewhat easily removed in the field if need be. The Gamo Hornet Maxxim is the Swarm Maxxim without the assembly.

        Supposedly you can buy the assembly from somewhere.

  6. Hmmm… Every gun is “accurate” within its effective range. Seems that the Swarm Fusion is a 15 yard rifle.

    Know that you don’t have time but a tin or two of pellets to break it in and a good cleaning might help the groups.


  7. B.B.
    Thank you and Pyramid for being willing to let the chips fall where they may with this series on the magazine loading spring guns. I’ll just volunteer that I think the Bandit pistol is a well made piece of metal if a bit expensive
    considering how it performs from the factory. Not completely resolved as a product because to get the accuracy the pistol has, the user has to do some other things, namely get a regulator. With the Umarex Synergis, I paid less money, and got allot more performance and value. I think that Umarex must be subsidizing this product at this price point. This rifle inspires confidence. It has a dead simple loading mechnism compared to other designs, power for hunting, and mine is good enough to shoot for points, mil spec trigger and all. The trigger will get better with use, but here’s the big deal. The Umarex is absolutely not hold sensitve at all. Very well mannered shot cycle, and mine prints bottle top size groups at 25yds if I’m on the computer, and dime size groups if I’m just shooting. I got rid of cocking lever detent mechanism, and found some nice foam for when it slaps closed. Will shape a nicer wood end for it, and yes, this rifle deserves a wood stock. Well worth the money.
    Keep up the good work!

  8. The question of a criterion for “accurate air rifle” has worried me, and I have asked a bunch of friends and Pelletgage customers (occasionally I get in discussions). The best I can arrive at is that it should be at least 2 MOA at 30 yds. This is off a rest, optimized hold. To be really happy, it ought to be 1 MOA (my best PCP rifle – tuned Marauder – can do it). I base this partially on what it takes to hit a tough Troyer rating field target. So…

    This gun had a good shooter testing, using a variety of pellets. Of eight tried, the best pellet had 3 MOA (see link for a calculator) at 10M. Most all the other pellets had fliers that opened the groups to something like 8 MOA. I would not call it accurate. 10 yds is easier than 20 or 30 in terms of the ballistics (or lack thereof).

    But most of us don’t have any specific criteria. You pick up your gun, hit the empty can target (or whatever), and it seems good 🙂


    • JerryC,
      My criteria for accuracy was, and still is, to shoot 1″ groups at 25 yards. This is my required accuracy for pesting sparrows from my bluebird nesting boxes. I was never able to achieve those groups with my Crosman Nitro Venom .22, nor my Diana RWS 34P .22. Now my Gamo Urban .22 is another story. The very first 10-shot group out of the box measured .155″ at 15 yards. Later shooting outside, I shot 10-shot groups of 1/2″ or less at 30 yards. This is what I call an accurate airgun and it will give rifles costing five times as much a run for their money at 50 yards or less.

      • A one inch group at 25 yds is 3.8 MOA, not all that accurate in my view, but I agree that some springers can’t do it, especially the higher velocity ones.

        0.155 inches at 15 yds (ten shot group) is an impressive 1.0 MOA. 1/2 inch groups at 30 yards is 1.6 MOA – I have a Gamo Urban, and it is about a 2 MOA gun, after shooting it a while (I think mine had the issue Tom found in his review – with plastic baffles interfering, which has mostly gone). So, like you, I consider my Urban to be accurate. It’s a nice gun overall, I need to go try again now with a single shot tray I got from PA.

        And I follow your idea, you consider the “need” of what you want to hit, the distance you likely will have such shots, and then find the capable gun. Pretty sure my Urban will hit small game out to 30-40 yds. It’s got good ergonomics, light weight, a decent trigger (after the screw change), and a useful energy level.

        • JerryC,
          So you have an Urban? Nice to hear experiences from someone who actually owns and shoots one. What pellet have you found to be most accurate? I only target shoot to verify my scope’s POI before pesting, so I’m not one who does a lot of target shooting. I’ve only tried a few pellets for accuracy. Most reviews show the JSB 18.13g pellet to be most accurate in the Urban. I started with those and then tried the JSB 15.89s, N&N FTT 14.66g, and CP 14.3g. The JSB 18.13g was best & CP 14.3 was the worst. I also did a thorough barrel cleaning with a patch worm and Ballistol.
          One thing you might want to check is the barrel band. Loosen the band to relieve any tension and then retighten. Some have shown to get the best accuracy by cutting the band off and letting the barrel free float. I do know that if the barrel is bumped, the band can hold the barrel off POA. I still like the idea of having the barrel band though and I am just careful to not bump the barrel.
          Regarding the baffles in the moderator, I used the shank of a drill bit to insure that there was no interference or pellet clipping. Mine was clean.
          Donnie Reed at Baker Airguns did a review on the Urban and found it to be amazingly accurate at 50 yards. He weighed and sorted the pellets and said the Urban was capable of 1/4″ groups at 50 yards. He has a video demonstrating his groups. I did a lot of research on various PCPs before selecting the Gamo Urban. I believe I selected the best available PCP for the money in regards to accuracy, and quality. It is basically a BSA Buccaneer with the hammer forged barrel made in England, and that, in and of itself, made this the best choice.

          • Donnie and I have talked about the Urban a few times. I bought mine online at the Walmart site, and it was a real bargain. The magazines are crazy priced, and mine was actually broken, thus the single shot tray.

            Paul Bracaglia did some work on mine before I even got it. I know he polishes the barrels of all the guns he works on with J-B. I have a bugbuster scope on it, and I’m very pleased overall. It has good power and accuracy, especially considering the price. I think it handles very well, even the plastic stock feels right.

            I agree, the BSA barrel is probably the key to our guns’ accuracy. IMHO, even premium brand guns, you are always hopeful you get one with a really good barrel.

            I’m shooting the 18 gr JSB’s, too. I have some Air Arms to try. Thanks for the pointer on the barrel band. Will look at it.

            • Interesting…yes, I agree the magazines are a bit overly priced compared to others. I the the BSA magazines are priced the same though. When I first got my Urban I had some issues with misfires and double feeds. This was my first experience with a PCP rifle and multi-shot magazine. I had to learn the correct procedure to cycle the bolt properly. Once learned, I’ve not had a misfire or double feed since. I wasn’t pulling the bolt back completely and the when the rifle misfired, I pulled the bolt back again with loaded a pellet on top of a pellet.
              When I looked at the magazine, I thought that there was some misalignment of the pellet. I disassembled the magazine and then when I saw how it indexed I realized there was no issue with indexing. I did find that the indexing spring was protruding a tiny bit and rubbing on the steel plate. I used a diamond file and removed about .030″ from the end of the spring and all was good. The only thing I see that could break is the o-ring which holds the pellets in place.
              You say that your magazine was broken? How so? Did you chronograph your JSB 18.13g pellets? I don’t have a chronograph so I am just guessing at the fps to be around 750-780 fps.

    • “accurate air rifle”
      JerryC, that’s a fair question, and I do have specific criteria…even if they are self-made. For an air pistol, if it can hit an empty .22LR shell at 5 meters, I call it “accurate” (my steel-breech Crosman 1322 with target sights and a 12″ barrel can do that with ease). For an air rifle, it should be able to hit that .22LR shell at 15 yards (basically, shoot one large hole at that distance; my HW30S and my Marlin 101 with .22 Quiet ammo {kind of makes it an air gun} can do this). For long distance shooting, it should be able to shoot an empty 12 gauge hull at 50 yards (my old Field Target rifle, an HW97 in .177, could do that all day…but many of today’s PCP rifles can far exceed that).
      *shrugs* That’s just one man’s take on “accuracy;” guns that meet those standards work well for me. =>
      Take care,

      • I like to convert all those types of target/range ideas into one MOA number.

        If you want to hit a .22 rimfire shell, it’s .22 inches wide itself, but you could “miss” left or right by 0.11 inches so that’s 0.44 inches horizontally (assuming you stand ‘em up) and we will ignore the vertical axis. At five meters, that’s 8.7 MOA, and at 15 yds, 2.8 MOA.

        A 12 ga hull at 50 yds is 0.800 plus the diameter of your pellet, or 0.178 and .978 at that distance is 1.9 MOA.

        So, you and I have a similar concept. I’m guessing your pistol shots are hand held, the gun is likely better than that…

    • Jerry,

      Agreed, you must have specific criteria and work within that effective range.

      IMHO, a gun is “accurate” if it can consistently hit it’s required target… having target size defined, the important thing to know is HOW FAR AWAY CAN IT DO THAT.

      The Swarm Fusion is accurate enough to consistently hit an aspirin tablet at 3 feet or a pop can at 20 yards or a barn door at 100 yards. For pesting I wouldn’t use one beyond 12-15 yards because I am not confident that it could consistently group pellets within a 1 inch kill zone.

      So for my applications (small game and pests), an accurate rifle must be able to consistently put all its shots (fliers excepted) within a one inch circle and it is up to me to determine how far we (the gun, pellets and shooter) can do that and not take shots beyond our effective range.

      Just my 2 cents


      • Hank, nicely stated. And following that line of thought, I am working on a slingshot range…yes, I think it needs its own range…and due to my current skill level, we are looking at something like a one foot square trap on a 5-yard range. =>

  9. Not trying to be a nitpicker, but the first sentence here says this is a “repeating breakbarrel spring-piston air rifle.” . Is this not a gas piston, or IGT as Gamo calls their version?

    Tom, I took out my Crosman 760 yesterday, and just shot Gamo Match pellets with it. Eight yards and ten pumps. I verified that my 760 likes those pellets. I believe you said you ordered some of these. I’d wait for your accuracy test until those pellets come in. So, maybe try the RWS Meisterkugeln rifle pellets, and the Gamo Match too. Inmygun, when I try BB’s, though I have got a few good groups with Daisy’s, normal groups are not good. But this plastic multi-pumper has pellet accuracy for 8-10 yards. I’ve gone to 10 pumps now because those critters zre so quick. They hear some noise from the shot, then jump in the air causing me to miss. And e gun is very quiet as I have a TKO muzzle brake on it. So, I’ve gone to ten pumps to gain velocity, giving the rats less time to react. Hopefully. Haven’t tried it in the chicken coop at night yet with ten pumps, but will soon.
    Pesting with a $35.00 air rifle. That’s me!

    • Birdmove,

      Airguns with gas springs or gas pistons are a subset of spring-piston airguns. Yes this rifle has a gas piston.

      I haven’t ordered the Gamo Match pellets yet. Probably won’t until, after SHOT because I want to be here when they arrive and I leave for Vegas next week. They are on my list though.


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