bsa ultra problem

[hawkfanz]

hello pw,ers my ultra reads full from the tank,but on fireing no air is released an pellet stays in the barrel,what do i need tto look at?and if i need to strip,how do i empty reservoir.any help appreciated,mmc type ultra.

[Ultrastu]

First the pellet probe seal .

Is it there or nicked .

I take it the hammer is actually going forward on firing (you can see if it's a multi shot in the mag well - below where the mag goes .) 

It could also be a small oring and it's circlip keeper that goes around the valve   stem if this is missing it will bleed air into the magwell on firing .

I need more information   

Is it a multi shot ?

Does air come out of the gun at all (mag well area or probe area when fired ) 

 

[oldypigeonpopper]

Hello, as above , first replace the breech seal, but it sounds more like an internal seal, buy a service kit it is not that difficult, 

[hawkfanz]

yes its a multishot,its off the wood now an u can see the the hammer strike i cant here or feel any air escapeing.just the noise of the hammer strike.

[hawkfanz]

probe seal is ok,

[Ultrastu]

OK. If no air is coming out any where (and there isn't a pellet jammed in the barrel ? ) 

Then either the hammer spring is broken .or you have valve lock ..which is when you have mistakenly put too much air in the gun  ie 250 bar plus .and the hammer can't tap open the valve 

 

[Ultrastu]

The most likely problem is that you have been shooting the gun and let the air pressure get too low ..around 50 bar or less and a pellet has stopped in the barrel .then you have fired a couple more on top of it .jamming the bore up tight .when you refill back to 190 bar ( max for a .22 mmc ultra ) 

The barrel won't clear and no air escapes the gun on firing .

 

If there barrel is clear and still no air escapes anywhere .then I suspect valve lock .the solution is to try and leaver the valve stem open with a screw driver a bit to release some air from the valve  as the hammer isn't strong enough .

What pressure does the gun equalise your tank at  ? Ie when your filing the gun and you hear the fill valve "tink " open ? It should be no more than 190 bar .if you up around 250 bar that's your problem  

[hawkfanz]

yeh stu barrel is clear,sounds like u might av nailed it with too much air,will try n lever valve open it is a 177 also.i was topping it up to loan to a mate,never ad a problem b4,in fact its the most consistant an accurate rifle ive got.

[Ultrastu]

Fixed it yet ? 

[hawkfanz]

no stu have ad bar in the vice to push open the valve,it moves against the spring ok then stops solid,dont know how hard it would be to open against pressure,but i would expect my 121/2 stones to be able to shift it,but no luck as yet also if i cant get air out,i wouldn,t be able to strip it.

[Gas seal]

Hi hawk fans if you look up XTX Air how to strip ultra multi shot on the website he shows how to release the air from the cylinder. I fitted a regulator to my ultra mmc a few years ago and I used the film on his website. Be aware of the loud noise if you have to release the air as he shows on the film. I released the air by firing the gun (unloaded). Hope this helps.

[Mice!]

9 hours ago, hawkfanz said:

no stu have ad bar in the vice to push open the valve,it moves against the spring ok then stops solid,dont know how hard it would be to open against pressure,but i would expect my 121/2 stones to be able to shift it,but no luck as yet also if i cant get air out,i wouldn,t be able to strip it.

If your gun has a gauge mate you can release the air by SLOWLY undoing the gauge,  listen for the air release then leave it at that, give it a few minutes have a brew and the air will be out, but I'm not sure if you will still have air in the gun though with it being cocked?

[hawkfanz]

update.....after trying allsorts of tinkering with hammer system to no avail,i put the tank back on to it,tto see what pressure it was at,200 bar.then i heard the valve go,tried again an back to normal working condition,havent a clue what was going on except maybe valve got jammed somehow.

[Ultrastu]

So it's at 200 bar .and once you reconnected the bottle .the locked valve has some how released its self and it now fires  as normal ? .

Well that's very strange  and a new one on me .

[Ultrastu]

This is the bsa valve as you can see there is very little to go wrong in there and the only thing I can think of that would stop the valve stem from being tapped backward and releasing air  is either a broken valve spring or a foreign  body in there jamming it up .

I'd be very tempted to shoot all the air out of it while you can and strip the gun to find the issue .it's likely to do it again and you may not be so lucky to have it release a second time .

[Ultrastu]

[hawkfanz]

good diagrams stu,yes really wierd whats happened av had the ultra 10 years now,an never ever had any problems before,but happy its workin ok,

[Rockhamster]

Ditto here, no issues with my Ultra to date, hope you get this one sorted👍

[Mice!]

10 hours ago, hawkfanz said:

good diagrams stu,yes really wierd whats happened av had the ultra 10 years now,an never ever had any problems before,but happy its workin ok,

Is it possible you haven't used it for a while and something had ceased?

[Ultrastu]

The only other thing I can think of is that your ultra has a depinger fitted inside (I've never seen one in any of mine over the years  ) but apparently the very early ones might have had them . It's basically a rod that screws into the air tube end of the valve and reduces the internal resonance of the air tube when it's fired .  If its some how slipped or been screwed too far into the valve it would stop the valve stem from being pushed in .

 

Here is Darrin fitting a depinger it's a long rod with an end cap that screws into the valve .some people fit them aftermarket  

Is your ultra sh. when u got it ? 

[hawkfanz]

yes stu bought 2nd hand bout 10 years ago now,got from a young lady who was giving up target shooting due to baby arrival.but its not used a lot these days my rabbits seem to have disapeared now.