Hatsan What is the diameter of the transfer port on the Hatsan 125 FAC and have you seen anything this unusual?
- Thread starter Airfuture
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Until you know the stroke ,tube size and piston weight ..
port work is a shot in the dark
Ive made 4 prototype break barrels of my own , 35 to 20:ft lbs. and ,have mucked up many tubes and time.. it’s not a waste as what I learned cost both.. knowledge is power …
longer stroke guns need a bit bigger port. That being said, they also need mass to tame spring return and to slow the piston advance..
Tuning a 12 ft lb gun vrs a 20 plus ft lb gun is worlds different.
Short stroke guns with big tubes like the Hw 80/35 , bsa lightning need smaller ports to generate the heat transfer cycle..
The Hw 80 as rewarding of a lifetime it’s had was great but still lacked a bit of refinement
96 mm stroke , 400 gram piston, proper made seal, not a parachute, and 3.9 mm port will net you the smoothest 25 ft lb dead blow shot cycle in any hunting gun you will have shot
port work is a shot in the dark
Ive made 4 prototype break barrels of my own , 35 to 20:ft lbs. and ,have mucked up many tubes and time.. it’s not a waste as what I learned cost both.. knowledge is power …
longer stroke guns need a bit bigger port. That being said, they also need mass to tame spring return and to slow the piston advance..
Tuning a 12 ft lb gun vrs a 20 plus ft lb gun is worlds different.
Short stroke guns with big tubes like the Hw 80/35 , bsa lightning need smaller ports to generate the heat transfer cycle..
The Hw 80 as rewarding of a lifetime it’s had was great but still lacked a bit of refinement
96 mm stroke , 400 gram piston, proper made seal, not a parachute, and 3.9 mm port will net you the smoothest 25 ft lb dead blow shot cycle in any hunting gun you will have shot
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I'd like to know the stoke length of a Webley Patriot. while beeing quite aware of the 80's stroke and piston. Yet the right TP is guesswork to find, it's rather experience.
I don't think that the longer stroke needs a larger TP, a bigger swept volume is rather able to cope with a too large TP.
It's not just the diameter it's, as much the length, say the issue is dead or lost volume of the TP, so the optimum diameter depends very much on the TP length, the longer it is the smaller the diameter must be, Try the 3.0 mm once, I bet it'll do fine and better than the 3.9 mm
So you made a HW80 with 96 mm stroke? This really can be a cool, powerful rifle half the way to the Webley Patriot.
I machined the stroke of a HW 35 up to 80 mm for this is the big flaw of the 35, its short stroke (and long pressure nozzle). A pity it worked properly for just a few shooting cycles, the cylinder extension had 30.3 instead of 30 mm diameter and the air broke through any seal after a while each time. But before I can confirm, the cycle was very smooth and the power output at about 16 ftlb @ 0.177
It was the 35 with 35 piston and 35 spring, 80 mm stroke and 10 mm TP length. Properly machined it could be my very favourite rifle, at moment it's just a remainder to a failed project.
And yes, you're right, powerful springers quite differ from such German popguns at 5.5 ftlb. (At that power not even a decent popgun )
And in general the proper caliber must be found for the action part. HW 80 and 35 as well as Diana 52 must have 0.22" everything else is a waste of metal. (The 35 can do fine at 0.177 but it's made for the larger caliber). Ther're so many good rifles out there which do well at 0.177" no need to restrain a HW 80 so badly.
Guess what people do. They machine down HW 80, 35 and Diana 52 pistons for less weight and short stroke them for that they do as smoothly as the HW 50 @ 12 ftlb or the 30 @ 5.5 ftlb. Pretty sure these rifles were not designed to be subject to such a castration.
Ok, the Germs when they're not allowed to exceed their 5.5 ftlbs they can hold a heavy gun at least.
I don't think that the longer stroke needs a larger TP, a bigger swept volume is rather able to cope with a too large TP.
It's not just the diameter it's, as much the length, say the issue is dead or lost volume of the TP, so the optimum diameter depends very much on the TP length, the longer it is the smaller the diameter must be, Try the 3.0 mm once, I bet it'll do fine and better than the 3.9 mm
So you made a HW80 with 96 mm stroke? This really can be a cool, powerful rifle half the way to the Webley Patriot.
I machined the stroke of a HW 35 up to 80 mm for this is the big flaw of the 35, its short stroke (and long pressure nozzle). A pity it worked properly for just a few shooting cycles, the cylinder extension had 30.3 instead of 30 mm diameter and the air broke through any seal after a while each time. But before I can confirm, the cycle was very smooth and the power output at about 16 ftlb @ 0.177
It was the 35 with 35 piston and 35 spring, 80 mm stroke and 10 mm TP length. Properly machined it could be my very favourite rifle, at moment it's just a remainder to a failed project.
And yes, you're right, powerful springers quite differ from such German popguns at 5.5 ftlb. (At that power not even a decent popgun )
And in general the proper caliber must be found for the action part. HW 80 and 35 as well as Diana 52 must have 0.22" everything else is a waste of metal. (The 35 can do fine at 0.177 but it's made for the larger caliber). Ther're so many good rifles out there which do well at 0.177" no need to restrain a HW 80 so badly.
Guess what people do. They machine down HW 80, 35 and Diana 52 pistons for less weight and short stroke them for that they do as smoothly as the HW 50 @ 12 ftlb or the 30 @ 5.5 ftlb. Pretty sure these rifles were not designed to be subject to such a castration.
Ok, the Germs when they're not allowed to exceed their 5.5 ftlbs they can hold a heavy gun at least.
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no need to. Just widened their ends a little and pressed them into the bore. Watching once in a while to find they don't move
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The length of the transfer port on this Hatsan 125 is 12-13 mm, diameter 3.9 on the cylinder, this insert diameter 4 mm...
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That short is good and those 3.9 mm won't hurt too much while no advantage with respect to 3 mm.
And stroke length, you're going to read as said above? My guess is about 110 mm.
Well those Patriots were decent guns, a pity their reputation suffered from the takeover by Hatsan.
To me they've always been sort of an extended HW 80
And stroke length, you're going to read as said above? My guess is about 110 mm.
Well those Patriots were decent guns, a pity their reputation suffered from the takeover by Hatsan.
To me they've always been sort of an extended HW 80
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I'm also thinking about honing the cylinder of the compression chamber, but... I will damage the protective metal and then corrosion will occur. Why aren't the factories honing the cylinder and barrel, installing plastic rings on the piston, better spring guides and other fine processing, it doesn't cost them much and they wouldn't be so embarrassed, Hatsan has disastrous locks on the barrel. I don't know where the Walther LGU Varmint is made (400 euros not much if it is made in Germany) but it has a great price and should be the standard for all spring airguns.
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Piston weight is 440 grams, compression chamber diameter is 29 mm, piston stroke is 117 mm, TP is 3.9 mm - 4 mm. The main spring is 360 mm long, wire thickness 3.6 mm, 48 windings, i.e. 46 active, OD about 21.6 mm
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That's a true magnum gun. I think the Gamo Hunter has similar stroke length and same piston dia.
But the Beeman Kodiak looks better
But the Beeman Kodiak looks better
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This is a new OEM Hatsan spring that was 440mm long, stayed cocked overnight and shrunk to 360mm.
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It just got set "scragged".
Kinda like said here
https://www.pyramydair.com/blog/2012/03/resizing-a-mainspring/
Arh for a small fee will preset the spring you order as well
Most just do like yours and put it in and leave it cocked overnight...
I do the scragging thing myself I find makes compressing / install easier and less chance you kink a new spring (opinion)
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I know about it but this is too big of a reduction, about 5% reduction would be reasonable. Quality springs are already stabilized and long max. load does not affect its characteristics...
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I think a new unset vs a set form my pile , but you get some " shrinkage".
Also with the set spring I don't have to fight in that extra inch or 2 to get it in the gun ..lol
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Hatsan 135 30mm piston 120mm stroke
Tp 4x 14
Hatsan 125 29mm piston 120mm stroke
Tp 4x14
Patriot uk 30mm piston 114mm stroke
Tp 4x15
Gamo h1250 pro 29mm x 118mm
3.8 x 20
Theoben eli. 31.4mm x 100mm
Tp 4 x 6mm
Dual magnum 31.4 x130mm 2 stroke
Tp ?
Im made a h135 with 30 x 125mm
It do around 34 fpe .25
100kg gasram.
Tp 4mm
Tp 4x 14
Hatsan 125 29mm piston 120mm stroke
Tp 4x14
Patriot uk 30mm piston 114mm stroke
Tp 4x15
Gamo h1250 pro 29mm x 118mm
3.8 x 20
Theoben eli. 31.4mm x 100mm
Tp 4 x 6mm
Dual magnum 31.4 x130mm 2 stroke
Tp ?
Im made a h135 with 30 x 125mm
It do around 34 fpe .25
100kg gasram.
Tp 4mm
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Also tested TP sizes
Hw80 3.2 mm oem
Bigger fps go down piston slam
Only heavy pellets.
The hatsans 4.0 4.2 mm depends on cal and pellet weight
Hw80 3.2 mm oem
Bigger fps go down piston slam
Only heavy pellets.
The hatsans 4.0 4.2 mm depends on cal and pellet weight
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Wow, that Hatsan 125x30 mm gasram must be a monster.
What is the Dual Magnum 2 stroke? A Theoben?
What is the Dual Magnum 2 stroke? A Theoben?
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