by Tom Gaylord
Writing as B.B. Pelletier

Avenger
Air Venturi Avenger.

Part 1
Part 2

This report covers:

  • Adjust the reg.
  • What’s next?
  • Beeman Kodiaks
  • JSB Exact Jumbo Heavy
  • Velocity
  • Baracudas on the lowest setting
  • JSB Exact Jumbo Heavy on the lowest setting
  • Dae Sung on the lowest setting
  • Discussion
  • A special test
  • Shot count
  • Trigger adjustment
  • Summary

Today I lower the regulator pressure setting and see what kind of performance we get with the Air Venturi Avenger. Because the regulator is user-adjustable and the hammer spring is also adjustable, the Avenger is flexible in its power settings. Today I hope we will determine the lower limit of that range, but because of the hammer spring adjustment there is a lot more to test. I will tell you everything I do, but I may not be able to test each and every possible combination, if the regulator settings and hammer spring adjustments have too wide a spread.

Adjust the reg.

First things first. Before you adjust the regulator you must first exhaust all the air in the reservoir. I read the manual carefully before proceeding. I was surprised that the Allen wrench that was included with the rifle wasn’t the right size for the air bleed screw. The wrench they sent is 2.5mm. It adjusts the hammer spring tension fine. We did that in Part 2.  But the bleed screw needs a 3mm wrench.

Once that was resolved I carefully turned the screw counter-clockwise. The manual says not to turn it out more than 2 turns, but I found only a quarter turn was needed. The air exhausted from 2,000 psi to zero in about three minutes. The reg. gauge was also reading zero at this point.

Avenger bleed screw
The 3mm air bleed screw only needed a quarter turn to exhaust the air from the reservoir. The rubber plug on the left of the bleed screw hides the regulator adjustment screw. 

Now the regulator can be adjusted. I read the manual for this, as well. To adjust the reg. they recommend you turn it as low as it will go, which is clockwise, until the screw stops. Then turn the screw back a quarter turn.

Avenger reg adjustment screw
Turn the brass reg. adjustment screw clockwise until it stops, then a quarter turn back.

Now, fill the reservoir to 300 bar. When I did I noticed that the reg. gauge needle stopped in the yellow, just below the recommended minimum setting.

Avenger reg gauge 1
After the reservoir was filled to 300 bar and allowed a few minutes to settle, the regulator gauge read like this.

The manual says to open the regulator adjustment (a counter-clockwise turn of the screw) slowly and allow the gauge time to catch up. I will say to do this EXTREMELY slowly, because even a slight movement of the screw affects the setting! I probably turned the screw 8 times, but I kept my eyes glued to the gauge needle, because I did not want to go through the process of draining and refilling the reservoir again. All those tiny adjustments probably turned the screw a total of another quarter turn and got the needle up to the start of the green area.

Avenger reg gauge 2
After all my adjustment the reg. gauge now reads like this. Two hours later the gauge was still in the same place.

What’s next?

Now that the regulator has been set to its lowest setting, I can either shoot the rifle for velocity with the hammer spring set to its highest tension, which it is at this time.  I adjusted it up all the way in the last test. Or I could adjust it as low as it will go. I decided on the first thing — leave it set as high as it will go — and see where the regulator adjustment has taken us.

We learned in Part 2 that regardless of the pellet used, the power stayed pretty much in the same place — 36 and a fraction foot-pounds. What will it do now that the regulator is set to the lowest pressure it can function at. with the hammer spring set as high as it will go? For this test I only shot a few of two different pellets.

Beeman Kodiaks

The 21.14-grain Beeman Kodiaks gave the following string.

Shot……….Vel.
1……………790
2……………747
3……………750
4……………749
5……………753
6……………751

The first shot was high because the gun sat awhile and the reg filled. But the average of the 5 shots after that is 750 f.p.s. For this pellet that gives a muzzle energy of 26.41 foot-pounds with a velocity spread of 6 f.p.s. In the previous test the average energy for this pellet was 36.94 foot-pounds, so with the reg set as low as it will go and the hammer at the highest possible setting the power range is just over 10 foot-pounds or 37 f.p.s. 

That tells us a lot about the Avenger. That will make the rest of today’s test much easier, because there isn’t that much more to test.

JSB Exact Jumbo Heavy

This was also shot with the reg. on low and the hammer at its highest. A short string of 18.13-grain JSB Exact Jumbo Heavy pellets gave me the following.

Shot……….Vel.
1……………802
2……………798
3……………793
4……………795
5……………794

The average for this string is 796 f.p.s. which gives an average of 25.51 foot-pounds, compared to the 36.65 foot-pounds average (at 954 f.p.s.) in the previous test.

Build a Custom Airgun

Velocity

In the comments to Part 1 Tyler Patner told reader RidgeRunner,

“The reg. is adjustable up to 3000 PSI (recommended maximum) but it can go a bit higher than that.  I found there’s plenty of room to adjust the reg down and still maintain similar power levels to where it comes set from the factory.”

Hammer spring set to the lowest 

Now I adjusted the hammer spring tension as low as it would go. That was three full turns of the adjustment screw counter-clockwise. Now both the reg. and the hammer are set as low as they will go. Let’s see what that does.

Baracudas on the lowest setting

Ten Baracudas averaged 722 f.p.s. on this setting. The spread went from 714 to 730 f.p.s., a difference of 16 f.p.s. The muzzle energy was 24.48 foot-pounds. Therefore, the power range of this pellet in the Avenger ranges from a low of 24.48 foot pounds to a high of 36.94 foot-pounds.

JSB Exact Jumbo Heavy on the lowest setting

Ten JSB Exact Jumbo Heavys averaged 782 f.p.s. at this setting. The spread went from 775 to 790 f.p.s., a difference of 15 f.p.s. That’s an average 24.62 foot-pounds at the lowest setting, compared to 36.65 foot-pounds at the highest setting.

Dae Sung on the lowest setting

Next I shot the 28.9-grain Dae Sung domes. At this lowest setting they averaged 593 f.p.s. with a low of 588 and a high of 610 f.p.s. — a spread of 24 f.p.s. At this velocity they averaged 22.57 foot pounds of energy, compared to 36.98 foot-pounds at the highest setting. This power spread is a little broader, but still biased toward high power.

Discussion

The Avenger has a narrow range of power adjustability. It’s capable of hunting power in all settings. But at the lowest power setting how many more shots can we expect? In the last test where the highest power was set we got about 55 good shots. From this point on all shots will be with JSB Exact Jumbo Heavys. I have already shot 11 shots with the hammer spring set at its highest, but the power doesn’t seem to be that much different.

A special test

Given the three strings at the lowest hammer spring setting, a total of 41 shots have been fired so far. I had noticed that the first shot in every string was faster if I waited a minute between strings. So, for the next 10 shots I waited a minute between shots to allow the regulator to fill. Remember — these are JSB Jumbo Heavys from here on.

Shot……….Vel.
42………….783
43………….783
44………….776
45………….781
46………….781
47………….776
48………….774
49………….778
50………….777
51………….779

The average for that string was 779 f.p.s. And the spread was only 9 f.p.s. Since hunters wait a long time between most shots, they should also wait long between shots when sighting in with most regulated guns.

Shot count

We got about 55 shots on a fill in the last test at the highest power. Now that the reg. and hammer spring have been dialed as low as they will go, how many shots are available?

Shot 52 went out at 776 f.p.s. Shot 61 was 773 f.p.s. Shot 70 was 773 f.p.s. Shot 75 was 768 f.p.s,. and then I waited 5 minutes before shot 76. Shot 76 went out at 782 f.p.s.

Shot 81 was 763 f.p.s. The pressure on the reservoir gauge read just under 2,000 psi remaining and the regulator gauge still reads the same as when the test was started.

Avenger reservoir gauge
After 81 shots at the lowest possible power setting the gauge reads just under 2,000 psi. The reg. gauge still reads 1,500 psi.

Shot 90 was 760 f.p.s. Shot 96 was 757 f.p.s. and I stopped shooting at that point. The reservoir gauge now reads 1,400 psi and the regulator gauge has now dropped back to that pressure as well.

So, the Avenger gets a lot of powerful shots on all power settings. I think I will leave it set where it is for the rest of my tests. It has plenty of power right now and it really uses air well. We shall see.

Trigger adjustment

The trigger was set pretty nice from the factory. It’s two-stage and not that heavy (that’s in Part 2). But stage two has some creep so I thought I would try to fix it.

Unfortunately the manual shows a trigger sear adjustment screw that’s not on the test rifle. It adjusts the amount of sear contact, so that’s probably a good idea because too little contact can lead to an unplanned discharge.

I adjusted the trigger pull weight screw and seem to have fixed the problem of creep. Maybe when I do the accuracy test I will have more to say about the trigger.

Summary

The Air Venturi Avenger is testing to be a very nice, powerful PCP with some features few other airguns offer. The power range is narrow, which makes this rifle good for hunting and, if accurate enough, for long range target shooting. Don’t forget it also comes in .177 and .25 calibers.

In the next test we will see how accurate it is. I am looking forward to that.