Prosport Problem

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Posts: 18
Joined: Sat Jan 27, 2018 9:00 pm
Location: Berwyn, PA USA

Prosport Problem

Sun Dec 30, 2018 7:26 pm

Ok members, I have a .177cal Prosport. I hear something moving/sliding inside the shroud area. The area I’m talking about is like a 4-5 inch area from the breach to where the metal tapers down to the barrel/shroud sleeve. So when I tip the rifle forward and backwards out in front of me with the butt in my right hand and the tip of the barrel in my left and dip the barrel down and up (we'll call it shaking for time saving/writing) is when I hear something is rolling/sliding.
My Prosport is tuned by none other than our Prosport doctor Nitrocrushr, who did an awesome job. The spring guide and top hat were done by a man who needs no introduction, Motorhead. Nitrocrushr helped me by trying to eliminate possible problems one at a time. First I made sure that all screws were tight/secured, I removed the scope to eliminate that possibility and still heard the noise. I then removed the action from the stock and checked the cocking lever's 2 screws (1 attaches to comp tube and the other attaches the cocking lever to the action/bottom of rifle) and they were very secure. I shook it again and I still hear it. I removed the guts and checked the spring, the guide the top hat, piston seal, the transfer port, the compression tube (which I left inside and attached to the cocking lever) and nothing was broken, damaged and/or missing. But I still hear the noise. I opened up the cocking lever all the way and left the breach area open, shook it and still heard it. I thought at first that it might be the delrin washers in the piston but when I removed the piston, those washers did not move what so ever. I am wondering if it could be a fragment of a pellet possibly. If so, then how could that be? Then I looked into the barrel from the muzzle end. Wondering if a baffle or an O-ring got clipped. I shined a flashlight in both ends and could see the o-rings and no damage was noticed nor did I see any other debris or damage.
I am at a loss. She still shoots superb and I know you guys/gals will probably suggest to leave it alone but the sound bothers me. I don't know what it is or how to find out. I do not want to remove the shroud because I am afraid of damaging the finish or being unable to put it back. Air Arms, I believe, has a lifetime warranty through PA (I think) but if I send it to them, they may just want to replace the rifle. Now if that happens, then I got to replace the JM spring with the oem one, replace the Motorhead guide and top hat with the oem ones along with the comp tube that came with it. I will also be giving up a Nitrocrushr lapped and polished barrel along with his tuning of the trigger. So I am at odds of going the PA route. So any and all help would be greatly appreciated as to my situation.

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Re: Prosport Problem

Mon Jan 07, 2019 7:14 pm

I owned a 1.77 pro sport very nice gun. I tuned mine as well my self, sounds like debris in there are somthing like that i think it will be a small piece of hardener dried up and dropped off it's used to set the shroud in place. try getting a small enough pipe to fit down the shrouded/baffled end between the barrel and shroud tube, i know easier said than done, ( not down the barrel its self). and tape the other end of the pipe to the hover and block with tape so it only sucks through the pipe, see if that works, failing that give air arms a call they can remove and re fit the shroud by heating it. Mind you if you have tuned and messed with you gun from standard, sorry to say but your warranty is void.

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Posts: 8
Joined: Wed Oct 26, 2016 10:18 pm

Re: Prosport Problem

Wed Feb 13, 2019 12:27 am

The baffles in the built in moderator can come loose. Shining a light in towards the barrel won't tell you much. You'll need to poke the baffle at the front and see if you can make it move back. You might have managed to shoot one (or more) of the baffles out, leaving the rest free to move back and forth.

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