Air Venturi Avenge-X Tuning Method

[superduty250]

I recently purchase the Tactical .25 caliber Avenge-X Bottle version and have run through about 2000 JSB 33.96 MK2 pellets while playing around with tuning. I have been using Steve AEAC's method and have gotten some excellent results. It seems that with his process, you end up with the optimum hammer setting somewhere close to where the "plateau" begins on the rainbow. Yesterday, I saw another method that says basically to find a regulator setting that gives a plateau fps 3 to 5% above your target speed. Then back off the hammer to get your target fps. This give a hammer setting just a little more to the left of the plateau of the rainbow. I did this yesterday and it seems to be a little more efficient shots per fill but not quite the tight es/sd that I got using Steve's method. With Steve's method, I got between 50 and 60 shots before the fps started dropping off. With the 97% method I got about 75 shots before the drop off. By the way, I have an external plenum and a little heavier hammer spring.

Anyone have any advice or comments about what method works for you?

I am attaching the graph of the rainbow test and the full shot string.

 

[Freddy J]

I'm shooting the same rifle, but I also shoot it tethered so I always have sufficient air supply. Haven't tried the 33.95 pellets only the 25.39 at 1800 PSI with HS 2 1/2 CW. Speed runs around 856 -873 FPS STD 2. Going to try a 22 barrel and see what I can do with it. I don't have the External Plenum as they are pretty hard to get here in the states.

 

[superduty250]

c88machining on ebay has the plenum that I purchased. I'm thinking about the .22 barrel myself but then I was watching AEAC Steve's video. He said the .25 was easier and more accurate so I have not done it yet. What tank are you using for the tethering? This is the plenum available on ebay. The gauge is placed a little differently than the one reviewed in the youtube video. I think that one is from South Africa?

 

[Jay308]

I would move the hammer adjuster a 1/8 at a time(up or down)and I bet you can get the ES/SD to tighten up.

 

[Freddy J]

I would rather have the one like they have in S Africa. The one om EBay sticks out too far.

 

[superduty250]

I would also, however it is almost impossible to get in the USA.

I would move the hammer adjuster a 1/8 at a time(up or down)and I bet you can get the ES/SD to tighten up.

I just received 8 tins of the 25 grain pellets from Pyramyd Air, so I am going to start over with those. I want as many shots per fillup as possible as I am only shooting paper. I'll do more tweaking with those. I am currently only shooting at 35 yards in my back yard. Once I do the tune, I will go to my gun club and do 50 and 75 (maybe 100?)