Tuning Air Venturi Avenger shot count

[BobsterIT]

I have played with my .22 Avenger trying to get a higher shot count. I fill to 4000psi and even at 1200 reg and HS set to 0 I can't get more than 40 shots before it drops of reg

I have charged the gun and set it overnight with no air lost. Anyone have any ideal what I am missing or what might be the cause?

I see others getting 100+ shots at 1400reg HS1 1/2 turns

 

[Pistonjohn]

I think it's just because the small tube this gun got, only 190cc I recall. My .25 at 2900 hs max has 22 full power shots, and I have comes to terms with it.

 

[BigTinBoat]

You're wasting air. Find a little shorter, or smaller diameter wire spring if you are unable to back hammer spring off anymore. What kind of velocity numbers are you getting.

 

[BobsterIT]

I still get from 830 to 900fts at low hammer spring setting maybe I need to look at bolt o rings?

 

[Camaro454]

IMO Air is leaking past the valve. Did you purchase this gun new? If this is not the wood stock version, there is an updated valve spool material.

 

[BobsterIT]

Yes bought the gun new Where do I find valve spool material and is that something I can fix or will it have to go back for repairs

 

[Booder98]

I was looking at how fast the velocity drops off over all of the shots this evening, and I had these numbers on my .22 Avenger set to one turn of the hammer and 1400 on the reg. Shooting 14.3 CPHP.

Starting at 4000 psi - 853 fps. After 40 shots - 2800 psi - 833 fps. I end up with around 80 shots, although 70 seems to be when I really notice the loss of velocity.

 

[BigTinBoat]

I still get from 830 to 900fts at low hammer spring setting maybe I need to look at bolt o rings?

That only takes one shot to check. Single piece of 1 ply toilet paper draped over the breech.

 

[BobsterIT]

Does anyone know where to get the Probe o-rings?

 

[Booder98]

They threw a couple in with the gun. The schematic says that they are:

.177 - says "HPA2-4 O-Ring." An -004 maybe?

.22 - 2.5mm ID x 1.5mm CS, 90 durometer.

.25 - 3.0mm ID x 1.5mm CS, 90 durometer.

https://www.theoringstore.com/store/index.php?main_page=index&cPath=368_52_1002 - it'll cost you more for shipping than it will to buy 20 of those.

 

[Booder98]

I still get from 830 to 900fts at low hammer spring setting maybe I need to look at bolt o rings?

That only takes one shot to check. Single piece of 1 ply toilet paper draped over the breech.

My QB78 ate a probe ring a while back, and you could feel it puffing on your hand. Not a gentle puff, either.

 

[igolfat8]

My .22 gets about 90 shots per fill. 2600 Reg settings shooting 18 JSB’s at 860-865, 4350 down to 2600

 

[BobsterIT]

So obviously the gun has a problem. I will look at changing out the probe o-rings 1st 

after that where else shout I look? I emailed Pyramyd Air support but as of yet no reply

 

[BigTinBoat]

So obviously the gun has a problem. I will look at changing out the probe o-rings 1st 

after that where else shout I look? I emailed Pyramyd Air support but as of yet no reply

OK, I'll say it again, check the hammer spring. If you have the hammer spring backed all the way out and you are getting 830-900fps (guessing a 14.3 or 15.9 pellet) then you have way too much spring. You should easily be able to back the velocity down in the 500-600fps range at 1200psi.

 

[qq200758258]

I usually get around 7-8. Magazines before it fall under reg

 

[queenks]

The hpa2-4 o-ring fir the .177 bolt probe.. do you know where to buy that.. doesn’t find on the oringsandmore.com website…

 

[Petey350]

What regulator and hammer spring settings are you guys using with the .25 version?