Problem with my FX Crown...

It appears I do have a problem with my Crown... I need a little help here...

After I unscrew my bottle from the rifle the low pressure side of my regulator vents its air through the bottle connection... This is not how it was when I received it, I was shown how to properly de-gas the rifle prior to adjusting the regulator pressure down... Help please...

The only other issue I noticed about the same time, was my regulator seems to settle down about 5 bar after I I adjusted it up from my 177 configuration back to the 25 cal after a couple shots... Is this normal,..???

Thank you for any help offered... Ken
 
Thank you, but I am certain It's not the bottle side venting... It's the low pressure side of my regulator that is venting out the bottle input after the bottle is removed, it vents very slowly... When I dry fire the rifle the once recommended time there is no more "pop"...

I can't say if it's the hammer spring tension or not, I started with the FX recommended settings using a caliper...

Ken
 
There's more, I mentioned this at the match yesterday to another fx user, (head scratching)… There's definitely a problem with my crown...

The small sliding block with the adjusting screw gets "stuck" for lack of better words... I notice this when I remove the action from the stock, it "pops" back to being loose with light finger pressure...

This part...

1569772136_8397016585d90d268078ce9.55415371_This_part.jpg


The labeled part in the image above gets "stuck" towards the adjustment knob side of the opening, has a slight "hang up" and requires me to push it back towards the breech, it then slides freely back and forth...

Ken
 
I think I got my problems solved, a little tweak here, a lil tweak there... And a new tune at 900 FPS...

Bottle unscrews correctly, the low side vents with a dry fire and my trigger feels good...

I will test a little more and shoot some groups when the rain stops...

Ken

I would avoid dry firing. I'd just loosen the reg gauge.
 
I would first begin memorizing the names of the major components, and watch the FX Crown disassembly / reassembly videos that Ernest demonstrates in the FX Airguns masterclass series. That knowledge and those keywords will help you identify problems and solutions much faster. 


FWIW, the only leaks that are a little bit of a pain to fix are in the reg. You can order A full set of o-rings from one of a dozen quality o-ring shops, or you can place an order for a full FX Crown service kit (FX part #1918) from an Fx service center.
 
Instead of dry firing FX USA told me to turn the reg. up just a bit and it will let the rest of the pressure out. I dry fired mine and the valve got stuck is how I know.


Two votes for this method, I will use this method next time I need to... From talking with another member it may be my hammer spring tension is too high and my regulator pressure too low at 115 BAR... Can others offer a better starting REG pressure for JSB 25.39s...???

One thing I notice is this: no matter what regulator pressure you have the cam mechanism has a point of adjustment where each click is felt to move the slide, out of this range the cam has zero effect after a certain point, a low limit... This tells me I can only increase the hammer spring tension from that point, and to lower it I must use the power wheel... I'm no dummy and it seems there is only one correct setting for this set screw that allows for the full range of adjustment of the power wheel other than increasing the hammer spring tension... Am I missing something here...???

Hey, I'm learning here...!!! And the part I identified in my drawing above is not identified on the parts diagram I downloaded directly from FX Sweden... I don't know what it's correct nomenclature is...

Ken


 
Can't offer you advice on the air blowing out, but I can attest that making regulator adjustments sometimes need a second follow up after a few shots. Also, this is important, the pressures can fluctuate easily 10bar just from temperature variations. Last night at 80F outside temp I filled up my crown to 250bar. This morning at 60F the pressure read 240bar, immediately I jump to conclusions that I have a leak somewhere, but stay put and leave it alone. Then three hours later as the temp rose to 72F the pressure read 245bar.

On the hammer spring adjuster being stuck. Does it feel like a mechanical locking up or could it be some oil on flat surfaces that creates like a suction effect? Have you unscrewed the hammer adjuster and checked it for burrs or other reasons it could be hanging up.

The other safe option to release reg pressure after the bottle is removed (other than loosening up the bottle side pressure gauge) is to turn the reg adjustment screw CCW. As soon as you do that the reg tries to compensate to higher reg pressure, but because there is no feed pressure it all leaks out. I agree, dry firing should be avoided.

If your FPS are all over the place when your set on a specific reg pressure and hammer spring tension that usually means the spring tension is too high of the set reg pressure. You would need to make adjustments to the grub screw on the hammer adjuster until your FPS ES start to settle in.

Well if your Crown is still under warranty, this would be the time to make that call and have them check it out.
 
Can't offer you advice on the air blowing out, but I can attest that making regulator adjustments sometimes need a second follow up after a few shots. Also, this is important, the pressures can fluctuate easily 10bar just from temperature variations. Last night at 80F outside temp I filled up my crown to 250bar. This morning at 60F the pressure read 240bar, immediately I jump to conclusions that I have a leak somewhere, but stay put and leave it alone. Then three hours later as the temp rose to 72F the pressure read 245bar.

On the hammer spring adjuster being stuck. Does it feel like a mechanical locking up or could it be some oil on flat surfaces that creates like a suction effect? Have you unscrewed the hammer adjuster and checked it for burrs or other reasons it could be hanging up.

The other safe option to release reg pressure after the bottle is removed (other than loosening up the bottle side pressure gauge) is to turn the reg adjustment screw CCW. As soon as you do that the reg tries to compensate to higher reg pressure, but because there is no feed pressure it all leaks out. I agree, dry firing should be avoided.

If your FPS are all over the place when your set on a specific reg pressure and hammer spring tension that usually means the spring tension is too high of the set reg pressure. You would need to make adjustments to the grub screw on the hammer adjuster until your FPS ES start to settle in.

Well if your Crown is still under warranty, this would be the time to make that call and have them check it out.

Thank you for all of that, I will be calling FX tomorrow as my Crown is only about three weeks old... I did better tuning it with just the chronograph, although the gauge read a lower than expected pressure it was consistent... Others said it was too low at 115 (per my gauge) The gauge that is obviously faulty is the bottle gauge...

I m going to watch more videos before I get into removing the hammer adjuster, it does feel like a mechanical lock up, if I cock and de-cock the action it will release, sometimes... I do appreciate all the help and advice I get here...

Thanks again... Ken