Cometa 300 Issue - Gun won't cock

[tugashooter]

I've bought this Cometa 300 brand new last year and have had lots of fun with it ever since, however recently I really got disappointed by this fault where the gun simply won't cock.

It happened during a short shooting session, nothing relevant to mention, there was no noise or weird behaviour before, I also never took it apart rather taking it out of the stock to put some grease on the spring and occasional screw retighten.

So basically now the gun won't cock, I can break the barrel and cock all the way through, the spring is resisting as expected but then it won't engage in the end.
I took the action apart from the wooden body for visual inspection and there is nothing unusual to mention, everything look good. When I've put the action and body together the gun did engage and I was able to shot once, then it wen't to not cocking again.
(repeated the disassembly-assembly process but nothing happened this time)

Any suggestions please?
Thanks

 

[Balders]

Has the trigger adjustment screws worked loose?

 

[tugashooter]

Has the trigger adjustment screws worked loose?

It is a two stage but not adjustable trigger (at least not by adjusting screws)

 

[marflow]

you would have to pull the trigger unit and inspected it Chambers has a good picture of the part but not in stock and i would also contact Cometa with what you found or the problem and see what they will do
that should not happen on a year-old rifle
it is a simple piston ride over and hook when cocking

 

[Balders]

Try pushing the trigger forward before attempting to cock it.
I know this isn't your model but it might help....

https://www.gatewaytoairguns.org/GTA/index.php?topic=106190.0

 

[Gazzy]

According to Big Dan, Cometa have a lifetime warranty on their rifles. Contact your RFD or Cometa directly and let them sort it.

 

[tugashooter]

indeed I can post it to Cometa for repair but I was hoping to avoid it if this is an easy fix. Sending it to Cometa means shipping cost back and forward to Spain from Portugal.
On the other hand if I start disassembling the gun I will probably lose warranty.

 

[tugashooter]

I don't understand a word from this video but he makes it look really simple (and safe) to make the trigger assembly to come out as a whole.
This makes it very tempting to take it out for visual inspection.
Any advice?

 

[Robbo]

Just remove to 2 end pins with a punch leaving the middle one. There are 3 on the piston tube above the trigger. The trigger assembly just falls out then. Most probable culprit is the sear that hooks onto the spring/piston and is tge one that pops out the top. The contact face nay be rounded and could do with filling back to a straight face if it's not engaging. After I took my trigger to bits it initially wouldn't engage but I just kept pulling the barrel down to the end of the pull repeatedly until it caught then it never happened again? BTW my one didn't even have an adjustment screw.

 

[tugashooter]

Happy new year everyone!
I finally went to disassemble the gun and removed the trigger. As a sub assembly the trigger seemed to be working fine, I could engage and release the trigger itself.
Aftwerwards I've put it back in the gun and the faulty behaviour is still there, can't cock it.
I am now tempted to go a step further and remove the spring, this way I would be able to simulate cocking it, and maybe see where it is hitting a hardstop or something.
Any ideas?
(I've attached a few pictures, could see nothing unusual.)

 

[marflow]

in the third picture is that fracture metal i see and yes i downloaded and enlarged or is it just mung
take the spring out
does it have a front spring top hat if so set it aside and try with the spring

 

[DaveT]

As above, I'd say the piston is cracked where the cocking link pushes against it.

 

[Neil54]

Those cracks are not on the holding face so I would have thought that wouldn't be the issue.

Possibly Coil bound, removing the top hat, if fitted, would prove this.

I would cock it out of the stock (not easy to do) and observe whats happening. Best with two people.

 

[tugashooter]

Thanks for your inputs, indeed those seem cracks, I will open and clean it to be sure.
I've tried to cock it out of the stock but it is quite a force to hold on and try to have a look at same time, so that didn't help. (unless I find a way to fixate the gun while cocking).
I am really tempted to take the spring out but it is my first time doing this, I want to be on the safe sife to prevent any risk with the spring when I release it. In the video above he has a certain setup for this, I probably hve to figure out something similar first.

 

[tugashooter]

Went back to the gun, there is no crack in the previous picture, that was only some grease.
I've cocked the gun out of the stock and took a picture where it seems to be the endstop, I don't think this stroke is enough to engage the trigger, it seems something is blocking the movement but can't understand what.
I've also found this weird think, looks a welded bit on the inside? I have no idea why that would be there, could this be the fault? It doesn't seem to be in the exact endstop though... (actually it might be the expected true endstop?)

 

[Neil54]

That silver bit looks like it could interfere with the trigger latching.

Time to get the spring out I think.

 

[paj]

Definitely need to get the spring out, clean and inspect everything.

 

[Timmy H]

Have you looked at the trigger sears? I stripped an older 300 years ago that wouldn't cock, the problem was the cheap metal used on the trigger sears, worn away to the point the sears wouldn't latch.

 

[Owain glyndwr]

Snapped spring,is my bet.

 

[tugashooter]

Have you looked at the trigger sears? I stripped an older 300 years ago that wouldn't cock, the problem was the cheap metal used on the trigger sears, worn away to the point the sears wouldn't latch.

My first look was at the trigger but in my previous post one of the pictures (pic 3) is cocking the gun out of the stock, and the trigger unit is not there. It will still find an endstop at some point.