FX My Fx Panthera needs some help

[niam11]

I recently changed the 700mm barrel to a 300mm for my Panthera and I just tested it out this afternoon. It still holding air, the regulator works fine, the speed is ok, the accuracy is excellent. But it needs too much air for every single shot and it’s super loud with a silencer on it. The air pressure gauge drops so fast and it shocks me. I couldn’t figure it out the issue. Please see the video link below. Thank you guys.

 

[Raider03]

I recently changed the 700mm barrel to a 300mm for my Panthera and I just tested it out this afternoon. It still holding air, the regulator works fine, the speed is ok, the accuracy is excellent. But it needs too much air for every single shot and it’s super loud with a silencer on it. The air pressure gauge drops so fast and it shocks me. I couldn’t figure it out the issue. Please see the video link below. Thank you guys.

There may not be an issue, the shooter barrel will require a high reg pressure to achieve the same speed. The pressure at the end of the 300mm barrel will be higher than the 700mm barrel. That will cause the high noise level. The high reg will waste more air with the shorter barrel.
Have you changed any settings? What velocity was it running with the 700mm barrel?

 

[Ratzy]

The issue is the amount of time the round is under pressure in a barrel. Longer barrel, greater final velocity.

Once the pellet leaves the barrel acceleration ends. So you require greater initial pressure to accelerate a round in a 300mm barrel than you did for the longer barrel at equal velocity.

That just takes more air. Shorter barrel either accept high air use or reduced velocity.

Also the air exiting the 300mm barrel contains more energy at exit than the longer barrel. More energy more volume.

 

[niam11]

There may not be an issue, the shooter barrel will require a high reg pressure to achieve the same speed. The pressure at the end of the 300mm barrel will be higher than the 700mm barrel. That will cause the high noise level. The high reg will waste more air with the shorter barrel.
Have you changed any settings? What velocity was it running with the 700mm barrel?

I reduced regulator pressure from 150bar to 100bar. I shoot heavy slugs with 700mm barrel and JSB 15gr pellets with 300mm barrel. The speed is about the same.

 

[Ries]

Arent there different hammer weights?

 

[Raider03]

I reduced regulator pressure from 150bar to 100bar. I shoot heavy slugs with 700mm barrel and JSB 15gr pellets with 300mm barrel. The speed is about the same

22 caliber? First option is to reduce the hammer spring using micro adjuster. Take the speed down to 850 fps. Does the air usage and noise improve ? How much?

 

[niam11]

22 caliber? First option is to reduce the hammer spring using micro adjuster. Take the speed down to 850 fps. Does the air usage and noise improve ? How much?

I tried to use the power wheel to make adjustments, but there aren’t changes.

 

[niam11]

Arent there different hammer weights?

I really don’t know about that. I will check. Do you know the OEM hammer weight? Thanks.

 

[Ries]

I really don’t know about that. I will check. Do you know the OEM hammer weight? Thanks.

Not really, you should check with Utah Airguns.

 

[niam11]

Not really, you should check with Utah Airguns.

The issue is fixed. You are right, this hammer is a little heavier than the OEM one. I just simply turned the hammer spring down to level 1, and now the rifle is shooting about 810 fps, and 4-5 mag per fill with normal noise level. Thank you so much.