Hammerli Pneuma Mod update

[mtbdrew]

Got the gun back from Umarex, they replaced the barrel, adjusted the tank so the fill port aligns correctly and, calibrated the pressure gauge.

Have about a hundred rounds through it since getting it back and it is shoot a lot more consistently now. Very happy with the gun and as the warranty is now expired it was time to proceed with some mods.

Took the tank valve off and did the three bottom hole plug mod, looking forward to seeing how this affects the chrony results.

This gun is very loud, the shot itself which I hope to tame soon with a TKO brake. However the gun also had a very sharp metal to metal clank and some spring twang. Took the hammer out and polished it and added some lube to the spring and other parts. Noticed the manufacture uses a regular screw threaded through the side wall to prevent over travel of the hammer. This was causing the metal clank every time the gun was fired. Removed this and replaced it with a 0.25" piece of 1 1/4" soft tubing from Homedepot. This appears to have cured the clank but will need to test tomorrow to see for sure once full pressure is applied.

Have a selection of pellets on order. Looking forward to seeing what type and weight this gun really likes.

[supertech77]

is there a barrel porting mod for this gun as there is the 850 hammer. http://www.network54.com/Forum/583201/thread/1226779394/At+last%2C+Pics+of+the+breech+and+port+mod. i know this increased the power a lot on mine.and the smoothness of loading.

[mtbdrew]

Interesting, the 850 has multiple port holes? The Pneuma/Hatsan AT44 on has the one. So far haven't had any issues loading pellets but if I do I will add this mod. As for widening and counter sinking it that is possible.

Anybody else tried it on there Pneuma or Hatsan AT44?

[rsterne]

IMO, one large port, properly sized and aligned, is better than several all the way around either the barrel or the valve.... The Hatsans are more efficient with the lower holes blocked.... and when they mod the 850, they only mod the bottom port.... The problem is the wasted volume in the groove around the barrel or valve feeding the other ports.... not to mention all the extra corners for the air to turn....

Bob

[mtbdrew]

Have no experience with a barrel that has multiple ports but whole heartily agree when it comes to the valve stem ports on the Hatsan/Pneuma tanks. Just doing the bottom three port plugs increase my shot counts from 20 to 30 at 190bar and 3 1/2 turns of pretension on the hammer spring. That tells me there was a lot of wasted air going out the bottom ports that wasn't making it to the pellet.

[Miguelor4469]

Have no experience with a barrel that has multiple ports but whole heartily agree when it comes to the valve stem ports on the Hatsan/Pneuma tanks. Just doing the bottom three port plugs increase my shot counts from 20 to 30 at 190bar and 3 1/2 turns of pretension on the hammer spring. That tells me there was a lot of wasted air going out the bottom ports that wasn't making it to the pellet.

Can anyone post some pictures as to how this is done? I have the Hammerli Pnuema in .177 and would like to do this to mine. And if possible what are the advantages to doing this.

[ralphtonka]

I used 2 part epoxy putty, disassemble,  opened targeted port,cleaned with brakekleen, inserted drill bit in port and stem area, filled with epoxy, cleaned up with a dremel and knocked high spots off on mini lathe. This was one of the first at44's to come to Canada, has been holding a couple years now. Some are using setscrews.......still need to fill channel.

[Miguelor4469]

newbielink:http://s678.photobucket.com/user/ralphtonka/media/IMG00161-20110412-1916.jpg.html [nonactive]

I used 2 part epoxy putty, disassemble,  opened targeted port,cleaned with brakekleen, inserted drill bit in port and stem area, filled with epoxy, cleaned up with a dremel and knocked high spots off on mini lathe. This was one of the first at44's to come to Canada, has been holding a couple years now. Some are using setscrews.......still need to fill channel.

Hi, what exactly does this do? I have the Hammerli Pnuema in .177 and took out the tank and it looks just like this. Any tips would be nice because I am under the impression that my gun is wasting air that does not make it to the pellet. Here is my e-mail if you like. I plan to have a nice FT gun and bought the Hammerli with this intentions due to my tight budget. if this is good then all I would need after this is a good quality scope and a front port.

[Miguelor4469]

newbielink:http://s678.photobucket.com/user/ralphtonka/media/IMG00161-20110412-1916.jpg.html [nonactive]

I used 2 part epoxy putty, disassemble,  opened targeted port,cleaned with brakekleen, inserted drill bit in port and stem area, filled with epoxy, cleaned up with a dremel and knocked high spots off on mini lathe. This was one of the first at44's to come to Canada, has been holding a couple years now. Some are using setscrews.......still need to fill channel.

Hi, what exactly does this do? I have the Hammerli Pnuema in .177 and took out the tank and it looks just like this. Any tips would be nice because I am under the impression that my gun is wasting air that does not make it to the pellet. Here is my e-mail if you like. I plan to have a nice FT gun and bought the Hammerli with this intentions due to my tight budget. if this is good then all I would need after this is a good quality scope and a front port.

izbetter@yahoo.com

[ralphtonka]

Much less air wasted/less room for the pressurized Air to expand. This forces the air into transfer port. This along with a sail (a washer) between valve spring and valve stem (sail helps to close valve quicker) can make a consistent and efficient combo, Gun becomes quieter, you will lose some fps, but you still have a hammer spring to lean on. If you are after max power this is not for you.  My at44 (.22) and Bt65 (.25) are both tuned this way........both are running in the 900fps area.

[jd72ke9z]

Was wondering how much it was to get this regulated. Was it esxpensive? Do they have longer barrel?