Power Plenum…benefits?

[peaceful_ruler]

I have a Taipan Vet Long .22 that I want to power up a bit for shooting 25 grain slugs close to 1000 fps. I’m using a 700mm barrel w/ barrel tension, HUMA reg, and a power plenum. Does anyone know if two power plenums would give an increase in power? Along with that…the point of a larger plenum is to have more air to maximize the power output of a longer barrel, yes? Therefore, there is no point to install a power plenum on a compact gun/short barrel, yes?

 

[heavy-impact]

No...In an airgun the plenum holds air at the regulated pressure. When the valve opens and the projectile starts to travel, the high pressure air expands and pressure drops. The larger your plenum the lower the rate of pressure drop so the projectile travels faster. The rule of thumb for maximum performance is 1cc per fpe. Larger calibers benefit most from a large plenum volume. A large plenum in line with the valve can cause a fairly loud ping. 70cc should be plenty on your .22

 

[Seeker]

If you have a 500mm barrel and you plan to shoot slugs then you do not need 72ccm plenum. The one from the Mk2 with high pressure is enough.

 

[Airgunmann]

Larger plenum means you could use lower reg settings to get the same speed

 

[Seth0764]

I have my vet set up the same as you minus the huma regulator. I had two power plenums installed, I removed one for some reason or another but I wish I hadn't. I'll be reinstalling it asap more power more shots

 

[peaceful_ruler]

I have my vet set up the same as you minus the huma regulator. I had two power plenums installed, I removed one for some reason or another but I wish I hadn't. I'll be reinstalling it asap more power more shots

With a 700mm barrel? What's the most power it can do with one PP and with two PP?

 

[Seth0764]

Yes 700mm .22 barrel, 2 power plenums reg is factory set 140 bar from what I can tell. I also put a washer behind the hammer spring. The maximum fps with a 25 grain slug is 970 fps I shoot them 930 fps. I have considered raising the reg to 150 bar for heavier slugs

 

[bigHUN]

I have a .25 MK2 original PP but with peek poppet, rear block and valve house re-machined (enlarged) air path.
Reg not exceeding 150 bars. Never ever shoot higher Reg.
37gr ZAN 1039 fps = 120 joules (89 fpe)
41 gr ZAN 1010 fps = 126 joules (93fpe).
44 gr ZAN 990 fps,