Umarex Air Javelin airbow: Part 3

by Tom Gaylord
Writing as B.B. Pelletier

The Air Javelin from Umarex.

Part 1
Part 2

This report covers:

  • Before we begin — the inside diameter of the gas tube
  • The test
  • Setup
  • First shot
  • Aiming
  • Loading
  • Shot away!
  • Move target to 11 meters
  • Shot two
  • Shot three from 10 meters
  • Back up to 17 meters
  • Adjusted the rear sight one last time
  • Shots 5 and 6
  • End of the test
  • Shots 7 and 8
  • Summary

Today I shoot the Umarex Air Javelin airbow for accuracy. I know that a lot of readers have been waiting for this! This will be an accuracy test, but as I said before, the AJ is such an important shooter that this report is going to proceed along different lines.

Before we begin — the inside diameter of the gas tube

Oh my, have some readers obsessed over this! They are busy redesigning the AJ the way it should have been, if only Umarex engineers were smart enough to have recognized it! I hear from AirForce all the time that they wish they were as clever as the people who redesign their airguns. But they know they aren’t, so they just let it ride.

The outside diameter of the gas tube measures 0.278-inches. The wall thickness of the tube measures 0.022-inches. That would make the inside diameter 0.234-inches. But when I measured the ID with my calibers I get readings between 0.135 and 0.155-inches. I know that my calipers are not the proper way to measure the ID of this tube, so I will hold up a 0.20/5mm pellet next to the tube and let you take a guess.

Air Javelin gas tube
That is a Sheridan .20 caliber pellet in the jaws of my Mitutoyo 8-inch dial caliper. The band at the base of the pellet measures exactly 0.2000-inches. The nose of the pellet that is next to the gas tube measures 0.1945-inches.

The test

I will shoot from a sandbag rest — the same as I did when I first shot the AJ at the SHOT Show. There I was 25 yards from the target. But Umarex had sighted the AJ in with a red dot sight and all I had to do that day was shoot it. Today I was on my own.


I started with the target bag 15 feet from the AJ. Yes I am using the back-up iron sights (BUIS), but since they detach from the AJ and I had to install them, I want to be certain of my shot! I taped a 10-meter pistol target to the center of the target bag to give me a more definite aiming point.

Air Javelin first shot
For the first shot I placed the target bag 15 feet from the AJ.

First shot

I have so many things to tell you about shot number one. First, the AJ is extremely easy to cock! Nobody will have a problem doing it. When the arrow is seated you cock the gun.

I was wearing my new hearing aids, so my description of the discharge sound will now be more precise.

The trigger is two stage with a looooooong first stage pull! The trigger then breaks heavily but cleanly.


I’m using the BUIS and you will remember that I told you that front fiberoptic is large. I decided to use a center-of-mass hold, which means holding the front orange dot in the center of the bull. That turned out to be a mistake, but I didn’t know it yet.

I will say this — the orange fiberoptic front sight gathers light extremely well. The thing glowed like it was battery-powered!


Load the arrow with the gun uncocked and on safe. It slides down the gas tube easily until it contacts the o-rings in the rear. Then it needs an extra push.

The arrow has two red “feathers” and one white one. On all bows the orientation of the odd-colored feather is important, but the manual makes no mention of it anywhere I can see. So I made it a point to load each arrow with the white feather pointing up.

Air Javelin loaded
The arrow is loaded.

Shot away!

The first shot went off with a loud report and a small cloud of CO2 gas. The arrow hit the target below the bull but in line with its center. Remember, I am holding the fiberoptic dot as close to the center of the bull as I can.

Air Javelin shot 1
The first shot hit the target about 3-inches below the aim point.

Move target to 11 meters

I moved the target bag out to what I thought was 10 meters. When I measured it from the tip of the arrow it was 11 meters. I adjusted the rear sight up and shot the second shot.

Air Javelin 11 meters
The target was moved out to 11 meters.

Shot two

Shot two hit the target about one inch below shot one and a little farther from the centerline of the bull. I had not known how much to adjust the rear sight up, so I didn’t go more than a full turn of the screw. I started hearing the clicks of the detent as I did this.

Air Javelin shot 2
Shot two hit below shot one and farther from the centerline of the bull.
It hit the back of the first shot, cocking it to the right.

Shot three from 10 meters

I adjusted the rear sight up a little and fired the next shot. It struck the target to the left of the first two. At 10 meters the fiberoptic front dot is almost as large as the bullseye.

Air Javelin shot 3
The third shot went to the left a bit. I’m still at 10 meters here, and the front dot is almost as large as the 2.5-inch black bullseye. I measured these three shots after withdrawing the arrows and the measure 1.617-inches apart, center-to-crenter.

Back up to 17 meters

I now moved back to 17 meters, which is almost as far as I can go in my little backyard. At 17 meters the front dot is larger than the bull! It is still smaller than the 8-inch kill zone of a whitetail deer, but I have lost a lot of precision with the target I’m using today.  That was what I meant at the beginning of this report when I said I probably picked the wrong sights for today’s test, but now I’m not so sure I did. Because of what I did buyers will have a good idea of how useful the BUIS are and can plan accordingly. I will guess that the BUIS will work to 25 yards on a deer. Beyond that a dot sight will be preferred, but in a hunting scenario you might want the dot for better visibility, anyway.

The first shot went “whump” — a decidedly different sound than the others had made. I could not see the arrow from where I sat so I walked up to the bag. The arrow was way low on the bag. That was why it sounded so different. Apparently the arrow dropped a by three inches when I moved back the 7 meters, so I had some more sight adjustments to make.

Air Javelin shot 4
From 17 meters with the same sight setting the arrow dropped another three inches.

Adjusted the rear sight one last time

I cranked the rear sight up as far as it would go and still allow me to hear the clicks. Let’s see.

Air Javelin sight up
The AJ rear sight is up pretty much as far as it should go.

Shots 5 and 6

The next two shots are from 17 meters with the rear sight cranked up pretty far. The first shot climbed on the target. 

Air Javelin shot 5
After the rear sight was adjusted up the next shot climbed back the three inches it has lost from the move.

Air Javelin shot 6
Shot 6 was higher and off to the left. I will tell you why in the report.

End of the test

At this point I realized that it was futile to continue. I had exceeded the fiberoptic sight’s range for accuracy. I was guessing where I was aiming and was off by several inches on every shot. I am almost certain that with a dot sight I can shoot near Robin Hood shots  (one arrow inside another) at this close distance, so it is pointless to continue.

Discharge sound

The AJ is loud. I call it a 4 on the Pyramyd Air sound scale. The sound does diminish as the gas bleeds down, but it still cracked on the 8th shot.

Shots 7 and 8

I went back outside when the sun was high in the sky and fired two more shots offhand from 20 meters. This time I was at the limit of my back yard, without shooting on an angle. Offhand I put two more shots into the target bag 1.5 inches apart and one inch below the aim point. This time there was no paper bullseye, so I aimed at the target bag itself, which was much easier. Perhaps we can stretch the range for the BUIS to 20 meters if you aren’t aiming at a small target. A grapefruit would be ideal!


I like the AJ a lot! It is just as much fun to shoot as I’m making it sound. And I think that once I get a red dot sight mounted we are going to see some real accuracy!

Umarex Air Javelin airbow: Part 2

by Tom Gaylord
Writing as B.B. Pelletier

Umarex Air Javelin
The Air Javelin from Umarex.

Part 1

This report covers:

  • However
  • The “barrel”
  • Not a toy!
  • Sights
  • Front sight
  • Rear sight
  • Adjust the stock
  • Install the cocking handle
  • Charging
  • One fact to bear in mind
  • Summary

At least one of you readers is really interested in the Umarex Air Javelin, just as I am, so today is Part 2. However, because this is an arrow launcher, this Part 2 will be a little different. I normally test velocity in Part 2, but the Air Javelin is better tested outdoors for that and today the temperature here in sunny Texas is 36 degrees, F. Yes, we have bright sunshine and the temp is supposed to rise to 62 late this afternoon, but my testing and photography work gets done in the morning, so the cold is hampering me.


That doesn’t mean I can’t shoot the Air Javelin (hereafter called the AJ) indoors. In fact, by shooting it indoors I will get a really good idea of how loud the report is. Remember that I could not hear it when I shot it at Industry Day at the Range in January. I’m making this report up as we go, so let’s get going!

The “barrel”

Several readers were inventing new universes for the AJ to inhabit. Like, what if a pellet could also be loaded into the hollow air tube the arrow fits over? Let’s look at that now.

Air Javelin barrel
This is the hollow air tube the arrow fits over. The CO2 gas comes up that tube to propel the arrow.

The gas tube/barrel is permanently attached at its base to the source of CO2 gas. Of course it is not really permanent, but it cannot conveniently be removed to insert a pellet — even if it was the right size inside. While such a feature is possible and even has been done by other manufacturers — nobody on the planet right now other than Umarex is offering an arrow shooter like the AJ for only $169.99.

Not a toy!

The AJ comes with a hang tag on the triggerguard that tells you it is not a toy. Believe it! I just hope that new airgunners won’t look at the arrow velocities that are displayed on the box at just over 300 f.p.s. and think, no big deal. Because a 170-grain arrow traveling at that velocity can do serious damage to tissue, and can kill! I said in Part 1 that you could take a deer with the AJ if you keep the distance reasonable, and the under 60-yard distance that I stated is about where most bow hunters take deer. There are powerful crossbows that can reach out farther and I’m sure a skilled longbow shooter can also do it, but hunters should always try to take their shot as close as possible — and that goes for airgun and firearm hunters as well. Let’s give the AJ the respect it deserves.


The AJ comes with what firearms shooters call back-up iron sights, or BUIS for short. They are not really metallic; that’s just a name they are given. You readers know that BB likes shooting with non-optical sights, so I will test them first. Before testing with them, they must first be mounted.

Front sight

The front sight attaches via an Allen screw that’s screwed down onto the Picatinny rail. First you slide the front sight onto the rail, which is easy, because the fixed sight dovetail is larger than the dovetail on the Picatinny rail.

Air Javelin front sight
The front sight attaches with an Allen screw.

Air Javelin front sight bottom
This is the underside of the front sight. On the right you can see the end of the Allen screw that presses against the Picatinny rail.

Air Javelin front rail
This is the front of the Picatinny rail where the front sight slips on the gun.

When the locking screw makes contact with the rail it pushes the dovetails on the bottom of the sight up to jam against the rail. It’s straightforward except for one detail. The screw has to make contact with the rail to do its job. Remember that a Picatinny rail has deep 5mm-wide slots spaced at regular intervals to hold accessories. The end of the Allen screw needs to press against one of the risers between the slots and not fall into a slot!

Air Javelin front sight on
Here you see the front sight on the airgun. The Allen screw that is in the rear of the sight is aligned with and pressing against the first riser on the Picatinny rail. Note that the rear of the sight is slightly elevated. Positioning it like this aligns the front of the sight with the front of the rail.

Rear sight

The rear sight attaches to the Picatinny rail and not to the long flat spot at the rear of the rail. The screw that tightens the movable jaw at the bottom of the rear sight base is also the crossbar that interlocks with a slot in the Picatinny rail.

Air Javelin rear sight underside
Here you see the cross screw that is under the rear sight. It draws the movable jaw tight and it also bears against a ridge in the Picatinny rail to keep the sight from moving.

The sight will not attach to the long flat spot at the rear of the rail because that cross screw gets in the way. But it will attach to the first slot in the rail, and since this is a peep sight we want it as close to our sighting eye as possible. So the last slot is where it goes.

Air Javelin rear sight mounted
The rear sight is mounted with the cross screw passing through the first slot in the rail. This is as far back as the sight will go. The sight is tightened to the rail by that large knurled knob.

Adjust the stock

Once the rear sight is mounted you can adjust the stock. I told you in Part 1 that there are 5 stops in the stock, but this time I pulled the rear part of the stock off and saw there are actually 6 holes for locking it. The last hole for adjusting the stock as long as possible is very hard to feel when the pin clicks in. 

I found that I needed the stock set in the first click back to see through the rear peep sight correctly. The length of pull is set at 14 inches on the nose. My sighting eye only sees a faint outline of the peep hole this way.

Air Javelin peep
The peep hole is sized just right, from what I can tell so far.

Looking through the peep, the front sight looks huge! I can see that my traditional target-type sight picture will be no good. This sight screams center of mass. It’s like a non-optical dot sight — and a big one, at that!

Air Javelin front fiber
The orange fiberoptic up front looks as large as the side of a barn! I will have to abandon my target-type sight picture and shoot for the center of mass with this one!

Install the cocking handle

The AJ is ambidextrous. The cocking handle will go on either side of the rifle. For this feature Umarex gets the Golden BB award for innovation! Remember — this is a $170 arrow launcher! How easy it would have been for the designers to figure they had already given buyers enough, just by the low price. Many companies would do that, but Umarex saw a way to add functionality cheaply and they did! Go back to my, “What makes an airgun ‘good’?” report, because this is a shining example! This is how it is done.

I held the AJ to my shoulder and pantomimed operating it to decide that I wanted the cocking handle on the right side. It’s slightly easier for me to cock that way and, since I have to take the gun down from my shoulder to load an arrow anyway, it isn’t an inconvenience. If this was a pellet rifle, I might have chosen the other side.

Air Javelin bolt right
On the right side of the AJ receiver you see the bolt with the screw hole for the cocking knob half-hidden by the receiver. It’s on the right side of the long cocking slot.

Air Javelin bolt left
Here is the view of the bolt from the left side of the receiver. Again the screw hole is half-hidden.

I used a ballpoint pen in the hole on the left side of the receiver to pull the bolt back so I could attach the handle on the right side. The spring tension is light and this is easy to do. Then screw the cocking handle all the way in. It has a shoulder that prevents the large handle from contacting the side of the cocking hole.

Air Javelin bolt top
This top-down view shows what the cocking handle looks like when it’s attached.


I spent a lot of time today showing you the setup. The manual covers all the same areas, but the instructions fall short of the things I have shown and discussed. Now it’s time to charge the airgun with an 88-gram CO2 cartridge (which you all know can also be a 90-gram cartridge).

Start with an uncocked gun. The forearm is unlocked by a square pushbutton on the right side of the receiver. Then slide the forearm forward for clearance. I would put 5 drops of Crosman Pellgunoil into the place where the cartridge screws in every time I install a new cartridge.

Air Javelin cartridge
Slide the forearm forward and screw the CO2 cartridge into the AJ. I recommend Crosman Pellgunoil on every cartridge.

One fact to bear in mind

Once the CO2 cartridge is installed and pierced there is no way to remove it without exhausting all the gas. The manual says to not store the gun with a cartridge installed. I don’t think they mean overnight, but if you are putting the gun away for a time, remove the cartridge.

The manual also says there may be some hissing and loss of gas as the cartridge is being screwed in. I experienced that. Once the cartridge stops turning freely, get set to screw it in as far as you can with a single turn of the hand. Even then you might have to get a second grasp to complete the motion. The gas will stop abruptly when the cartridge is sealed.

Would a shutoff valve at this location be desirable? Certainly. How would they do it? Given the way the AJ is designed at present, it wouldn’t be easy. Bear in mind that the design of the gun is for slimness and convenient handling., I think I will take that over saving some of the gas. Remember, there will not be that many shots, even from this giant cartridge. 

Air Javelin 1077 AS
The Crosman 1077 AirSource had a valve to stop the flow of gas from the 88-gram CO2 cartridge. See how clunky it was!


I spent my morning setting up the AJ to shoot. She’s now got sights, a cocking handle and is charged with CO2. It’s 12:30 p.m. and it’s still just 54 degrees outside. Next week, cold or not, I will shoot it for you. Time for me upload, edit and schedule this report.

This report will go differently than others have, because of what I’m testing. But we will still get to know the Air Javelin as well as we possibly can.