Any US importers carrying this gun?

[darkcharisma]

I got one of the cheap clamp on chronographs from Aliexpress and was able to take some readings off my liberty this evening. I am thinking I need to turn the reg as it seems a little slow but IDK for sure. What do you guys think.

I dont think you'd want to run 14.3 CPHP's any faster than that.  You should see how well they group at 50+yds at this speed for a baseline if you do decide to turn up the reg.

In my experience, CPHP's usually start getting a little unstable beyond 865-875 fps.
 If you decide to run heavier pellets, you could probably get away with turning up the reg. to maintain the 850-900 speeds that most diablo type projectiles prefer to run at.

 Generally speaking, if you want to run pellets at speeds over 900 , they need to be a minimum of 25 or 28 grains.
Of course, Your mileage may vary.

Yes my mileage is different. I run CPHP 14.3 above 950fps out of my Gauntlet and I can hit a birds head at 50yards (2 confirmed kills). And a light pole at 100 yards. It's not that unstable...seems to flight as straight as the wind allows.

My Liberty drives them at 950fps stock setting. I opened the barrel port to 85% of .217 and got maximum 990fps and min 970fps. This is just barrel porting, not shimming hammer spring or turning the reg adjuster yet.

[Gertrude]

Ok guys a little help please so I don't bave to go through 35 pages.
I am sitting on the firing line as I type this, and do not have the manual with me. This is oh the second time out with the gun.
I want to lighten the trivger5 pull weight.
What screw do I adjust ?
Thanks

[TheSaint]

Ron,
You'll have to remove the trigger group to lighten the trigger the correct way. It involves removing the rear most screw, and moving it to the hole that has the blanking screw in it.

It takes some trial and error. Don't think it can be done at the range unless you have the tools with you and about an hour.

[Gertrude]

Thanks
Yeah, probably not going to do that here at the range.

[cosmic]

Yes just swap the screws , The one behind the trigger with the one all the way back.. You will have to remove the trigger since the back dust cover screw is put in upsidedown, head toward the breech.. Swap and adjust until it trips the sear, adjust back until you like it. If you back it off enough the safety will work...

[TheSaint]

Ron,
Even with the heavy trigger, and without upping the reg, shimming the hammer spring or opening up the barrel port to 11/16 th's, what are your initial thoughts about the Nova?

[Gertrude]

Ron,
Even with the heavy trigger, and without upping the reg, shimming the hammer spring or opening up the barrel port to 11/16 th's, what are your initial thoughts about the Nova?

Well, All I can fairly comment on is the firing cycle, and the smoothness of the cocking lever. Both seem very nice and function very smoothly.
 I can not comment on how well it groups due to we got completely blown out with wind today. maybe nexy weekend I can do some groupings and shot strings.

 Hopefully I'll get some time during the week to take a inside look at it and do the trigger work while I'm in there.

[darkcharisma]

Hey guys. I got a problem with my Liberty. I am now unable to pull the lever back to load. Still air in tube and pellets in mag. It got stuck pretty good. Im Suspecting the hammer and trigger mechanism got bind up somewhere. Anyone had this problem?

[Back_Roads]

 Is the mag stuck in the receiver ?

[darkcharisma]

I tore it up and found a loose screw underneath the lever.

[Lastdog]

Any pictures? Like to know what screw I need to lock tight.

[darkcharisma]

Should be a Philips head under the lever linkage.

[Lastdog]

Thanks for the heads up.

[darkcharisma]

I haven't seen anyone talk about working on the valve yet. So here's what the valve looks like. There are some areas I think it can be improved upon.
 
I think I am going to mill some 45 degree angles here and there and open up the trench.

[Abefroman]

Ok, I got my Liberty .22 wood stock in saturday 1-26-2019.  I immediately cleaned the barrel and it didn't seem that it was all that dirty.  I ran 4 patches through it, then a mop.

pumped it up to 4000 then started shooting it.  initially, over my cheapo chrony, it was shooting CPHP 14.3 around 790 fps, then started shooting faster.  after around 40 - 50 rounds and topping up the cylinder, it was shooting CPHP around 860 fps.

then something really strange happened - I switched to JSB Heavy 18.13 and it was shooting exactly the same as the CPHP 14.3 !!!!  WHAT ?  so I loaded up a few more magazines with both CPHP and the JSB's and,  exactly the same FPS !!!    After a few more fills and a lot more shooting, it maxed out around 890 FPS

So, the next day - sunday - I started shooting again and it stared out around 790 FPS, but gradually increased to around 850. 

Does the barrel need to "warm up" or something ?  why does it start out low and eventually creep up in FPS ?   Maybe it needs to "break in" some ?  I'm assuming that it's regulated, so I would think that the FPS should stay pretty constant, right ?

So, I took it apart, turned the brass regulator disk 180 degrees counterclockwise, then added two washers to the hammer spring = 0.1 inch added.   I then shot it over the cheapo chinese chrony and maxed out at around 980 FPS with the 14.3 CPHP.

I dont know how you guys are getting 950 FPS right out of the box and 1050 FPS with 18 grain JSB's after reg adjustment and hammer shimming !!!

This morning I ordered a Competition Electronics ProChrono Digital Chronograph

Hopefully, a lot of my strange readings are due to the crappy chinese cheapo chrono I was using !!!    ProChrono should be here wednesday 1-30-19 and I plan to repeat all of my testing

So far, I really like the gun, however, the FPS and accuracy is all over the place.   But, maybe its just me, the cheapy chrono, and maybe it needs a several hundred pellets through it.   I guess time will tell.

one other note - after ONLY TWO uses, the magazines broke.  I took them apart, fixed them, but the spring keeps coming out of the little hole in the back piece.  I stretched the coils on the spring on one of them, put it back together, and it kinda works.  I need to do the same to the other magazine.  However, both of my Gauntlet magazines work flawlessly in the gun.  In fact, they seem to fit the breech even better than the 2 mags that came with the gun.  The original mags seem to be a little too thick in the breech and dont let the internal wheel rotate freely.  I'll probably file down the body of the magazine just a little bit to see if I can get it to fit and work better.

Right now, my Gauntlet is more accurate, but the fact that the Liberty can be adjusted and made much more powerful, and especially the awesome cocking lever mechanism,  I'm definitely keeping it.

one more note..  IT AINT LOUD !!!  in fact, it's probably quieter than my gauntlet.  I ordered the crosman silencer from pyramid air, but, I'm not sure I'm even gonna need it !

Thats it for now... please comment !!! 

[darkcharisma]

My liberty did the same at first. 850fps then 950fps with 14.3grains. I just fill it to 3600psi and shoot it down to 2400psi to keep the spreads low. The point of impact seems to change from left to right as the fps increases.

 
I shimmed the hammer spring and turn 1/4 turn on the wheel. Now it's shooting like it's unregulated from 1050 constantly down to 950 with 14.3 grains. This is after a barrel port and shortened regulator pin on the input side. The brass wheel adjusts tention on your valve spring. So you have to play with your hammer tention and the brass wheel to get Your desired fps within a shot string. There's no way to tell what the regulator is doing unless you mounted a nanometer in the plenum

[Rat Sniper (AKA: PaulT58)]

Anyone have pictures of the 2 trigger screws you are swapping to improve the trigger action? 

[nervoustrigger]

why does it start out low and eventually creep up in FPS ?   Maybe it needs to "break in" some ?  I'm assuming that it's regulated, so I would think that the FPS should stay pretty constant, right ?

Couple of possibilities.  One is the issue that Duy described, that the regulator is nonlinear and its setpoint is higher when the reservoir is filled to near max pressure.  With the symptom you are experiencing, what would be happening is the gun would be operating at a partial valve lock.  The pressure in the valve is higher, therefore the hammer is unable to knock it open sufficiently and the velocity is reduced.  Note the opposite velocity trend would occur if the hammer were hitting the valve harder...the velocity would start high and then taper off as the fill pressure falls.

The other possibility is the regulator is creeping.  Meaning when the gun sits idle for a while, high pressure from the reservoir seeps slowly through the regulator.  Thus the first shot will be slower than expected (or faster, depending on how strongly the hammer is hitting the valve).  In some cases it can persist for a few shots, however for a gun at this power level and assumed plenum volume, I would expect it to only affect the first shot, maybe 2 shots.  So if you're seeing the velocity gradually rise over several shots, I'd be more inclined to blame it on the nonlinearity that Duy described.

I don't know how one would go about addressing nonlinearity.  I would think that's a fundamental design fault.  The closing force is varying substantially with input pressure.

Creeping on the other hand is fairly typical with a new regulator, and may go away with some break in as the regulator's valve seat material wears in to match that of the piston.

In both cases, your best bet is to carefully adjust the hammer spring to find the velocity knee.  That's where the system will be least sensitive to variations in pressure.  To find the knee, keep increasing hammer spring preload until the velocity no longer increases.  The back off until the velocity falls to about 97% of that maximum.  So if it maxes out at 950fps, back off until it's about 850 * 0.97 = 825fps.

[Abefroman]

Umm, Ok, did you mean that if it maxes out at 950, to adjust down to .97 x 950 = 920

right now the regulator has one half turn (180 deg.) counterclockwise on it   The hammer spring has been shimmed by 0.1 inch.

should I adjust the regulator ?  increase ? decrease ?
should I add more shims to the hammer spring ?

I would imagine that I should (like you said) set the regulator adjuster and then add shims to the hammer spring until the FPS maxes out, and then remove hammer shims until I get 0.97% of max velocity.  At that point, if I dont get the velocity I'm after, adjust the regulator again, and then add/delete hammer shims until max, then remove to 975.

a very iterative process.

I think first I'll adjust the barrel port, then go from there.

thanks !!!

[superchikn]

Anyone have pictures of the 2 trigger screws you are swapping to improve the trigger action?

https://www.gatewaytoairguns.org/GTA/index.php?topic=149431.msg1555137#new
Go to the top of the page post #660.