Hatsan Flashpup from 23 to 46 joule Tuning

Check out BROTHER'S IN AIR over on the you tube channel.he has made some very good video's on the Hatsan flashpup.I have .22 & .25 cal flashpup's.have mod's to the.25 cal. .193 dia transfer port and receiver,then hammer spring adjustments.you need a crony to check speed of shots.I have adjusted mine to push the JSB'S king heavy 33.95 mk2 pellets in the 840 fps range at the top of the power curve.i get 10 shots in the 800's,next 10 shots all in the 700's fps.then refill back to 200 bar.any way check out BROTHER'S IN AIR,on you tube

My guess is that they do it the same way they do the At44. If you look at the Parts breakdown for the AT44 and the Flashpup the valve stem is listed as #2312.

In the reduced power market the valve stems are larger in diameter, to block the amount of air that flows thru.

If you look at the pic below (I borrowed from the SA forum) of the 3 stems shown the bottom one will put out the most power, the top one the least. If you were to take the top stem, chuck it in a drill press and hold a file to it while spinning you could make it just like the bottom one.

Thank you so much for that picture. You the old saying "one picture is worth a thousand words"? Yep!

Are they different Hatsan Stems or are they different cuts on the original stem.

Thank you so much for that picture. You the old saying "one picture is worth a thousand words"? Yep!

Are they different Hatsan Stems or are they different cuts on the original stem.

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Pretty sure they are all "original" stems. If you look at the bottom one (highest power) you notice the part where the hammer strikes (far right in pic) is not tapered as much. I would think this is since the higher power one will likely be getting struck harder, so they made it beefier

Would be nice to know the part #s. In looking through the Hatsan diagrams I can see they have more than one for the same action. I had noticed the different striker ends but your explanation now makes that difference make sense.



Thanks again for posting the picture. Now when I disassemble mine I'll have and idea of what I've got and if it's worth it to acquire another or machine it myself.

Thank you very much! Now i have an idea where i have to look and what i can do(or not). Do you know if i can buy these original valve stem as an single part somewhere?

Greetings Ronny.

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Not know where you are from (you mention Spain) I would suggest you get a hold of:

https://hatsanairgunsusa.com/ - if in the USA

http://www.airgunspares.com/store/product/14387/Hatsan-AT44-Valve-Pin/ - if in the UK

or

http://www.hatsan.com.tr/index.html - if somewhere else

Ronny who sell this valve stems.

Can you send me the contact.

I need on for a Atp2

Ronny, did the valve stem fit the flash pup ? It appears the same valve stem fits several hatsan models !