Benjamin Trail NP All Weather .22

[northlander30]

Hey everyone, I was chronographing a few of my rifles the other night and I noticed my Benjamin Trail NP All Weather was shooting rather low in velocity. Last time I chrony'd this gun it was shooting Polymags in the 710FPS range and Crosman 14.3gr in the 690 range which is odd since the Crsoman is lighter. But anyway that's what I was getting from those 2 pellets. I tried it again 2 nights ago and it was shooting the 14.3's with a highest velocity of only 545FPS. I contacted Crosman and they said it sounds like the gas ram has lost power and or has failed. They also told me that these gas rams they put in these guns are only rated for 15,000 shots. I can get a new gas ram a Crosman OEM part but I was wondering, Can an NP2 gas ram be fitted to work in these guns? I asked a long time ago and the answer was no they couldn't. I am interested to know if anyone has fitted an older NP with an NP2 gas ram and how it worked out.



Ian

 

[acs]

 You probably already have tried 1 big drop of silicone lube in the chamber, and cleaning the barrel immaculately then seasoning it..?

My experience with np/np2 is when the actual gas ram 'springs' a leak, it fails quick and completely. Or at the very least it continues to get worse and worse very quickly, is yours doing that..?

No, the new np2 guts will not fit in a an older np gun.

jmo

 

[northlander30]

The more I shot it the lower the velocity got. The lowest was 500FPS and then i just quit and scratched my head. OK I will order the OEM gas ram.

 

[Windmill01]

Have you looked at the piston seal yet? It may be falling apart. Just a thought.

Gary

 

[fishinwrench]

Unless the outer dimensions of the gas ram are different, I don't know why they wouldn't be interchangeable. 

 

[ptthere]

Unless the outer dimensions of the gas ram are different, I don't know why they wouldn't be interchangeable.

It is my understanding that the NP2 ram has a larger piston diameter and is not directly interchangeable.

 

[ranedouglas]

. i have found that np2 rams fit into many different guns - not just crosman-made ones. i used them a lot because they were cheaper. in the .22 prowler , the np2 ram actually chrono'ed a bit slower, harder to cock, and had a more harsh firing cycle. the np2 rams are not rounded at the top like the others. the np2 rams have a bit longer stroke, too. if your barrel is accurate, i would just order the correct ram, a piston seal, and a breech seal - and rebuild it. hope that helps. - raneman.

 

[northlander30]

Have you looked at the piston seal yet? It may be falling apart. Just a thought.

Gary

Gary, I have this covered as well. I ordered the gas ram and a new piston seal. I figured while I was in there I would check the seal as well. I may even just simply replace the seal while changing the ram.

 

[donwalk]

i had the NP Trail in 22.

i never could get satisfactory performance, or accuracy, from even after much 'tweaking/tuning'

the best chrono reading was 652 fps; a far cry from advertised velocity.

 

[Windmill01]

Ian let us know how it turns out. I’ve been tinkering with the rams in my two NP’s and I feel that the sweet spot for a ram is between 55 and 60 kilos. My 177 has the original ram and it has taken a lot of practice to get it to shot accurately..It also kills scopes while the 22 np is far easier to cock and is easy to shoot, but it has a Gamo ram in it.

I would be very interested in knowing what power your new ram is and how it performs.

Good luck

Gary

 

[ptthere]

Ian let us know how it turns out. I’ve been tinkering with the rams in my two NP’s and I feel that the sweet spot for a ram is between 55 and 60 kilos. My 177 has the original ram and it has taken a lot of practice to get it to shot accurately..It also kills scopes while the 22 np is far easier to cock and is easy to shoot, but it has a Gamo ram in it.

I would be very interested in knowing what power your new ram is and how it performs.

Good luck

Gary

60 kilos? Maybe this is a dumb question, but that is around 140 pounds... Shall I assume that the rating is at the piston itself, not the cocking effort at the barrel?

 

[Windmill01]

Ptthere my bad, you are correct,I’m getting lazy, I should have typed kilogram-force (kgf). The term newton is more widely used especially in the states.

Newton

Definition: The newton (symbol: N) is the SI (International System of Units) derived unit of force. It is defined as 1 kilogram·meter/second2.

History/origin: The unit newton is named after Isaac Newton for his contribution to classical mechanics – particularly his second law of motion, which states that the rate of change of momentum of a body is directly proportional to the applied force, and that this change in momentum occurs in the direction of the applied force.

Current use: As an SI derived unit of force, the newton is the preferred unit of force, and is widely used in scientific contexts, particularly in physics. In everyday use, units such as the pound-force are sometimes used in place of newtons in countries like the United States.

Gary