Benjamin Trail NP will not zero after one month

[ivanpros]

Hi,
I bought the Benjamin Trail NP (.22) from Pyramid Air back in late June. I have been taking it out on the weekends to shoot. As of yesterday I went out to shoot and It is now shooting high (Crosman Premier Hollow Point). I adjusted the vertical adjustment down and it is at it's limit, but still shooting 2 mil dots too high ( just a note that I am very proficient with the scope adjustments and adjust them for my Gamos all the time).

I changed the scope to a Leapers to see if it was the scope, but it also shoots high with the vertical adjustment all the way down.

This looks like the opposite of barrel droop. Are there any known issued or does anyone have any other tips on what to check for? 

[Jman]

did you accidently let the barrel slam shut before? Thats all I can think of. Shim the bottom of the front mount?

[ivanpros]

Nothing out of the ordinary when loading pellets. I just tried 2 shims (35 mm cut to size) and it is not enough. My grouping is still good when I shoot at 10 yds and 25 yds, other than just too high.

[Jman]

weird. You could contact crosman...thats about all else I can think of besides shims

[ivanpros]

I guess  I will try Ccrosman next. Can the shroud affect the barrel in any way or is it just aesthetic and sound dampening?

[dkwflight]

Hi
Shim the scope mount.

[amb5500c]

The shroud can affect the poi if something happened that causes it to clip the pellet as its leaving the barrel thereby deflecting the flight path.
Richard

[Jman]

As far as I know its only aesthetic and sound dampening! Cause the way it works is its just an empty pipe over the barrel that captures gas behind the pellet as it leaves the barrel

[ivanpros]

o.k. since I am getting tight shot groups I can make that a low priority for troubleshooting. I also tightened the barrel screw, for which I found was a little loose, and used goo gone on the barrel, but all that did was tighten my shot groups.

[Wee Hooker]

 Any chance your lifting your head as the shot goes off?

[josh3rd]

have someone else try to shoot and see if it may be your error or the rifle.  2nd, switch mounts.  the one thats in the front will be switched with the one in the rear.  3rd, over tightening of the barrel shroud can change poi.  try 1/16, 1/8 or 1/4 turns.

[LeadHead]

had that same prob with my NP All Weather. Swapped out my scope and got 2 slices of film for shimming. I figure it was the scope and seems there is some droop in their mounts too, according to my CMM at work, approximately 4=5 degrees

[john]

Got my Trail last March. If your groups are tight, you are very fortunate.

1. ANY change to the shroud will change poi. I have done ALOT of experimenting w/ my shroud.

2. The shroud is not easily removed due to factory glue (loktite knock off?) on muzzle threads. You would definitely NOT want to be trying to tighten that any further.

3. If you do remove the shroud, lay the gun over on its side, sight along the top edge of the compression tube and down the barrel. Presence or absence of droop is easy to see. In fact you can do that now.

4. Buris Signature scope rings for Weaver mounts plus a set of their plastic inserts will allow you hopefully to cancel out enough misalignment to get your elevation adjustment back to the middle of its range. I'm using them to cancel droop with no problems...well worth the $$$.

Keep us informed...oh, and welcome to GTA...i'm new too.

[ivanpros]

Well, I went ahead and removed the shroud of the barrel and I also found the factory glue and metal debri, which could be from the pellets or gunk left by manufacturer; It was dirty. Next I looked at the barrel and noticed that it was bent upward so I went ahead and bent it back down and it fixed the problem, but I am perplexed of how it happened. If it was dropped the shroud is so thin it would have showed damage and it would have taken a good bang to bend it. Well here are my  shot groups at 10 yards. I left the 2 shims in the fron scope mounts; since I did not want to bend the barrel too much.

[Muppit]

i have read dry firing a crosman/benjamin break barrel will bend the barrel upward. i had this problem with my g1 extreme as a beginner i would just push the pellet out and dry fire the rifle and i noticed that after a while i was always hitting a couple inches high read up on it someware and thats what was said caused it to bend upward........dave

[john]

So you've known all along how to fix droop and you just been sandbagging us. 

[ivanpros]

Actually no, everyone's comments got the mental wheels moving and common sense set in  . The answer may be right in front, but can't see it until someone else removes the mental obstacles out of the way. That was my first barrel bend and glad all went well.

Thanks to all!

[john]

No Ivan, I was kidding Muppit.  Glad you fixed your problem. I learned something new.

[ivanpros]

Thanks John. Just a note that I test fired it without the shroud after every attempt at bending it and it was just enough to feel the barrel flex slightly. When I screwed the shroud back on it did slightly change my point of zero, but was very small and I was able to adjust back to zero.

[ezman604]

Excellent, glad you were successful in straightening the barrel. Overtightening the shroud end can buckle a barrel slightly. Airgunning is fun and you learn a lot if you stick with it. One point I want to make, dry firing does not cause a bent barrel. And it's not just Crosman /Benjamin break barrels either, but ANY springer/NP gun can be damaged by dry firing. Dry firing is cocking the gun and shooting it without a pellet loaded. This can cause main seal damage and possibly damage a spring.
What causes a barrel to get bent is a different beast. What happens here is you are cocking the gun and before you can engage the sear to cock the gun, the barrel slips from your hand and slams shut. It can also happen if you cock the gun and let go of the barrel while getting and loading a pellet. If the anti-beartrap or sear fail, or you inadvertently hit the trigger while the barrel is in the break position, it will slam shut. This will most definitely cause the barrel to get bent, most likely crack a stock, possibly cut a finger tip off or worse. ALWAYS hold the barrel until you have completely loaded it and locked it into the firing position!!!!
Keep us informed on your progress.
Happy Shooting!!!!
Dave