Hatsan Bully 25

[Jorgo]

Need some advice at barrel port.

I take out the bullys barrel to see how big tje barrel port is.

The caliper shows 0.181

I want to shoot pellets and slugs

Can i make it bigger? Is my question or longer to 0.200 or 0.195.

The pellet probe has 0.137 i think it will be stable at .0100.

I have instal a Altaros regulator.

Altaros send me on that i can adjust to 170 bars.

Actually it is on 150 bars and shot the jsb 25 gr at 950 fps and the 34gr at 850 fps at lightest hammer spring set.

Like bevor at that pressure without reg

Have no fps drop with the reg it seems like the plenum in the gun is large enough.

Tomorrow i install the scope and make some string test.

Gun look with the reg not bad

It just fills now realy slow.

 

[Seth0764]

Very cool! I'm interested in the shot string.

 

[Bigragu]

Yeah, me, to Jorgo. Show us the shot string! 



Thank you you for posting your results so far.

 

[Jorgo]

So for first i must correct somthing.

I dont like glasses but maybe i think about it

The reg pressure was not 150 bar it was 145 or 140 like on the image

First test was with jsb kings..filling the gun to 3350 Psi

Here the results in meter/second

At this speed tje kings dont perform well

960/970 fps are to fast out my rifle for them

From shot 35 comes the drop

I have cast some slugs with a mp.mold and shot just for fun a few

I know they need a higher pressure not just 145 bar

Dont perform good at 750 fps

Next one was JSB Heavy 34gr

Becouse the light a have much errors at the chrony i will try it another time to make a full string

Here are a few shots with them

 

[Seth0764]

Those are some nice shot strings. Where did you get the regulator? 

 

[Jorgo]

Hello Seth, i order the Regulator from Altaros 

It can be set till 170 bars.

Just the filling times are longer with this bottelregulator 

But it makes a good Job

 

[Jorgo]

This rifle have a real big plenum

 

[Jorgo]

The tube with the valve have 34 ml inner plenum...without the block

 

[Jorgo]

Cant take down the valve from the tube with two people ..who knows how they put it on the tube mabe with some maschine



i want to block the.lower holes and.line up the valve with the tp port...bit cant do it now

 

[Jorgo]

..

 

[Jorgo]

Orginal Barrelport was 0.177 

I enlarge it to 0.190 ..maybe go step furter to 0.20.

Transferportsize was around 0.23 inch

 

[Jorgo]

Pelletprobe original 0.138 sized down to 0.10 inch

 

[Jorgo]

Velocity and power test

With Jsb 25gr and 34 no changes at 250 bar with full hammer strike.

With the cast slugs 48 grains velocity

Before portwork and probeworke was 820 fps...after 903 fps or 11 fpe

Sttrange that with tje pellets i have no changes at max power just gaining more speed at lower psi but it reaches a maximum and more pressure dont give more speed.

With the heavier slugs this little porting give me 80 fps.more speed very stabel from 250 till 300 bar after it drops