by Tom Gaylord
Writing as B.B. Pelletier

Gamo Swarm Maxim
Gamo Swarm Maxim repeating breakbarrel air rifle.

Part 1

This report covers:

  • Loading
  • The feeding mechanism
  • Velocity JSB Exact RS
  • Gamo PBA Platinum pellets
  • H&N Baracuda Match 4.50mm heads
  • Back to JSB RS
  • What about dry fires?
  • Cocking effort
  • Trigger pull
  • Trigger adjustment
  • Evaluation

Today we look at the velocity of the new Gamo Swarm Maxim multi-shot rifle. Of course this rifle is so different that we will also be looking at several things we don’t normally see. Should be an interesting report.


I was concerned about loading the magazine because I have some experience with other multi-shot breakbarrels and none of it is good. But the Swarm magazine loads like any rotary PCP mag, so there is no worry. Like most of them, there is an o-ring that’s around the entire rotary wheel and part of it intrudes into each chamber to hold the pellets. Consequently, they don’t just drop in. You have to push on their bases a little to get the heads past the rubber.

The magazine is spring-loaded to advance to the next loaded chamber. So when you load it, you turn the rotary wheel against the spring. It is not as hard as many PCP mags that are designed the same way. After each pellet is loaded the wheel stays where that pellet was loaded, so the rotary wheel never slips and runs all the way back to the first pellet hole.

Gamo Swarm Maxim magazine
A portion of the rubber o-ring is seen on the right side of the chamber. The pellet head must be pushed past it.

The feeding mechanism

Several of you asked to see the feeding mechanism. Well, it’s kind of like Yehoudi. He’s the man inside your refrigerator who turns on the light every time you open the door. The Swarm feeding mechanism is inside its plastic housing and is not visible from the outside, but I know that a probe has to push each pellet into the breech when the barrel is closed. Yehoudi works the same way. [From a popular song of the early 1940s “Who’s Yehoudi?,” made famous because of the popularity of classical violinist Yehudi Menuhin on the Bob Hope radio show.] Bottom line? I ain’t a’gonna tell ya ‘cause I don’t know.

Gamo Swarm Maxim feed mechanism
Those wire legs move the feed mechanism.


Gamo Swarm Maxim probe
The barrel is partially cocked with the magazine removed and the feed probe is seen sticking out on the right side.

What I can tell you is that loading the magazine into the rifle and taking it out again are very easy and straightforward. Have no concerns — you’ll be able to do it.

Velocity JSB Exact RS

The first pellet I tested was the lightweight JSB Exact RS. They gave some interesting results, so I will show the entire string.


The average for this string is 1063 f.p.s., but it’s meaningless. As you can see, the Swarm I am testing needed to burn off some oil before settling down. I will come back and test this pellet again, after I test all the others. It looks like it will settle in the 930-950 f.p.s. range.

Gamo PBA Platinum pellets

Next to be tested were Gamo’s PBA Platinum pellets. If the rifle is ever to achieve its advertised velocity of 1,300 f.p.s., it should be with this 4.7-grain pellet.

This pellet averaged 1218 f.p.s. in the test rifle. The spread went from 1202 f.p.s. to 1227 f.p.s. That’s 25 f.p.s. As you can see, the Swarm has already settled down. At the average velocity this pellet generates 15.49 foot pounds of muzzle energy.

H&N Baracuda Match 4.50mm heads

Next I tried some H&N Baracuda Match pellets with 4.50mm heads. This pellet averaged 813 f.p.s. in the Swarm, with an 18 f.p.s. spread from 804 to 822 f.p.s. At the average velocity, this pellet generates 15.63 foot-pounds of energy at the muzzle.

Back to JSB RS

Now it was time to re-test those JBS Exact RS pellets. This time they came in at an average 944 f.p.s. The low was 932 and the high was 955 f.p.s., so a spread of 22 f.p.s. That was where I expected it to be, though as the rifle breaks in it may speed up a little. At the average velocity this pellet generates 14.51 foot pounds of energy.

Operation of the repeating mechanism

You have to experience it to appreciate it. Since the safety is manual, just cock and fire. I shot a 10-shot string through the chronograph in about one minute. Once I realized how reliable the feed mechanism is, I was completely at ease using it.

What about dry fires?

The top of the pellet magazine tells you how many pellets remain in the mag. All you have to do is remember whether the rifle is cocked and therefore loaded.

Gamo Swarm Maxim magazine window

The number of pellets that remain in the magazine is easily seen.

Cocking effort

The Swarm has Gamo’s Inert Gas Technology (IGT) gas spring and piston, so the cocking effort is constant throughout the cocking arc. I estimated it at 28 lbs., and when I tested it, it took 32 lbs. of effort to cock the rifle. It’s well within reason for the power of the rifle.

Trigger pull

The trigger on the test rifle breaks at 2 lbs. 7 oz. It is a two-stage pull with a light first stage and a definite stage 2. I can feel the tiniest bit of creep in the stage 2 pull, but I rate the operation of this trigger as fine.

Trigger adjustment

I said I would adjust the trigger in this report and let you know how that went, so here goes.

I followed the directions in the owner’s manual (declare a holiday!)  and was able to adjust both the length of the first and second stages of this COT trigger! I does work as advertised. However most other adjustable triggers allow the adjustment of the weight of stage two, so this one is different. It adjusts the length of the stage two pull. The weight remains the same.

I got the trigger with a very short first stage and a short second stage. The pull weight remained where it was — 2 pounds 7 ounces. But now this trigger is very sweet. You know — an adjustable trigger that actually adjusts isn’t that common. I praise Gamo for getting this one right!


So far I am quite pleased with the Swarm. If it turns out to be accurate, as I have already heard owners proclaim, then we have a world-beater on our hands.

The hump from the magazine feed mechanism will turn off some buyers, but I think Gamo has put a lot of value into this rifle. Accuracy is next.