Falcon fn12 light Hunter leaking power fault

[Matt W]

Pick this up last week and it's a lovely looking thing and shoot really nice however once you fill it up to 190 take approximately 20 to 30 shots then it starts leaking from around the action area gets louder and quieter when you open and close the bolt.

When it has emptied itself it also leaks when filling until the pressure gets up


The other thing it does is it creeps up in power with every single shot, so each shot gets progressively more powerful through the shot string.

It is however extremely accurate so Id like to get it working 100%

Could anyone direct me or recommend anybody near Barnsley South Yorkshire to sort this out.

Kind regards

 

[Omega man]

@ped is your man

 

[ped]

your filling it to high and that is why you're getting a climbing shot string -about 165 bar is about right i've found unless reg'd
sounds like the stem is at fault and may just need a clean out of the valve

 

[Sharpsman]

Needs a good service and a new firing valve or reface it . Lovely accurate little guns but a poor shot count but that to be expected given the size of the tube and barrel .

 

[Matt W]

I was always told falcon can take 190 although I appreciate maximum fill sn't necessarily optimum fill

 

[ped]

if it was reg'd i'd maybe look at running 190 which is the max fill but at that pressure the shot string is ascending till you get down to 165 bar
not sure on fac settings as i haven't an fac and 190 maybe ok

 

[airgunnut]

the manual says 200 bar but it was recomended to fill to 180 as thats the sweet spot, at 200 bar the power will be a bit low, after about 10 shots it will get to about 180 bar and the power would have creeped up to maximum.
I've had a Falcon FN19 hawk (multi shot with separate cocking hammer), sold that to get a single shot FN19, then i got the FN8 pistol and then a Falcon Prairie, i still have all 3, the FN19 is about 27 years old (i got all the Falcons new)
i have never known anyone fill a Falcon as low as 165 bar, at that pressure you will only get about 25 shots from a FN19.

Pick this up last week and it's a lovely looking thing and shoot really nice however once you fill it up to 190 take approximately 20 to 30 shots then it starts leaking from around the action area gets louder and quieter when you open and close the bolt.

When it has emptied itself it also leaks when filling until the pressure gets up


The other thing it does is it creeps up in power with every single shot, so each shot gets progressively more powerful through the shot string.

It is however extremely accurate so Id like to get it working 100%

Could anyone direct me or recommend anybody near Barnsley South Yorkshire to sort this out.

Kind regards

it sounds like the gun needs servicing (reseal) did you get the gun new or second hand? if it was second hand then there is a very good chance thats its been played with, the FN's were self regulating, the valve springs were balanced to mach the pressure and ports

 

[ped]

the manual says 200 bar but it was recomended to fill to 180 as thats the sweet spot, at 200 bar the power will be a bit low, after about 10 shots it will get to about 180 bar and the power would have creeped up to maximum.
I've had a Falcon FN19 hawk (multi shot with separate cocking hammer), sold that to get a single shot FN19, then i got the FN8 pistol and then a Falcon Prairie, i still have all 3, the FN19 is about 27 years old (i got all the Falcons new)
i have never known anyone fill a Falcon as low as 165 bar, at that pressure you will only get about 25 shots from a FN19.

it sounds like the gun needs servicing (reseal) did you get the gun new or second hand? if it was second hand then there is a very good chance thats its been played with, the FN's were self regulating, the valve springs were balanced to mach the pressure and ports

200bar is over the swp of 2750psi (stamped on the breech of an fn)
funny how most on our falcon group on cheesebook all fill to around 165-170 bar and a properly set up fn19 will do about 65 shots at this fill with an fn12 giving 35ish shots in .22
most falcons these days have had someone tinker with them usually a spring kit or port from the robber

 

[airgunnut]

200bar is over the swp of 2750psi (stamped on the breech of an fn)
funny how most on our falcon group on cheesebook all fill to around 165-170 bar and a properly set up fn19 will do about 65 shots at this fill with an fn12 giving 35ish shots in .22
most falcons these days have had someone tinker with them usually a spring kit or port from the robber

My apologies you are correct about the swp of 2750. i have only just started using my airguns again after 10 years so the 200 bar fill pressure is from my falcon prairie.
my experiance says that you only need to port the falcons if your going over 14 ft pounds (in .177) over this without porting just wastes air, i have found the Fn line very accuret and constant without any porting ot regs, the only thing needed is to replace the original spring as the standad springs weaken, going from 11.6 to 9 ft lbs in just over a year, i have tried a number of factory springs but all went the same way. the other thing i added was a plenum chamber depinger.

 

[Blackmax]

My apologies you are correct about the swp of 2750. i have only just started using my airguns again after 10 years so the 200 bar fill pressure is from my falcon prairie.
my experiance says that you only need to port the falcons if your going over 14 ft pounds (in .177) over this without porting just wastes air, i have found the Fn line very accuret and constant without any porting ot regs, the only thing needed is to replace the original spring as the standad springs weaken, going from 11.6 to 9 ft lbs in just over a year, i have tried a number of factory springs but all went the same way. the other thing i added was a plenum chamber depinger.

Ped’s the man when it comes to these rifles, he even makes spare unavailable parts and supplies the seals.

I’ve had two over the years and 165 bar was best fill pressure.

 

[ped]

hardly the man Andy as many know more than me and anything above sub 12 i have no experience
i do try to keep them going though

My apologies you are correct about the swp of 2750. i have only just started using my airguns again after 10 years so the 200 bar fill pressure is from my falcon prairie.
my experiance says that you only need to port the falcons if your going over 14 ft pounds (in .177) over this without porting just wastes air, i have found the Fn line very accuret and constant without any porting ot regs, the only thing needed is to replace the original spring as the standad springs weaken, going from 11.6 to 9 ft lbs in just over a year, i have tried a number of factory springs but all went the same way. the other thing i added was a plenum chamber depinger.

there are a few size ports for the different calibers and barrel length and fac rated along with fac rated valve springs and hammer springs
you're right about original hammer springs weakening and i spec'd up a near to original size for sub 12 from a reputable spring maker as thankfully parts fitted that make one over the top can be put back to std

 

[Aston_Shooter]

My FN12 Lighthunter likes 165 bar. I'm not sure how many shots I get in .20, but I think it's around 40 (worth using).

 

[Cambelski]

I'm on the look out for fn12 bits if you know where to look or who to talk to.

Cheers