Hatsan AT44, Bullboss air/exhaust valve pin change

[@MsLampalampa]

Thank you sir for the explanation :)

[@voltron_5]

Excellent video! I need help with loosening and removing the valve body from the air tube (Hatsan AT44). It's on there very tight (as if someone used lock tite on the threads or something to keep from leaking because even the vise doesn't help, and I don't want to tighten the vise any more. It's as tight as it can be without causing too much stress on the air tube; if I haven't already). I've heated the air tube with a blow dryer, a steamer and none has helped. Now the tube is in the freezer and immediately I'll heat up the tube end (valve body area) and place in vice again, hoping this would help. I've used WD40 already hoping it penetrates deep enought on the valve body threads. I have a similar situation on a BT65 airtube which I have put aside for now - the flat areas on the valve body for the wrench application has been slightly damagae and to avoid any further damage, I've designated this cylinder as a non regulated tube to be used with an external regulator. If it leaks, I will have to find a way to loosen that valve body as well). I have a heat gun in my Amazon shopping cart to use in place of the steamer/steam gun. I Any suggestions?

[@gardenshedgunsmith1648]

Did you get this taken care of? First off, Make absolutely sure that there is no pressure left in the cylinder. If there is it will make it next to impossible to unscrew the valve body. Are you using a round tube clamp to hold the tube? If there is loctite on the threads a hairdryer probably won't get hot enough, especially if the permanent "red " was used. The heat gun will be a better option. There really is no reason it shouldn't unscrew without damaging anything.

[@voltron_5]

I was able to get it off after all without the heat gun (after I ordered the heat gun). I was also worried that if I used the heat gun not to use too much heat that might compromise the integrity of the tube. I kept the tube on the vise tight enough just to hold it in place. I used a metal rod through the fill port as leverage (about the same thickness as the fill probe). But now I also have to remove that end as well because it developed a leak (likely the valve seating) after a few fillings. That end seems to be even tighter. I think I'll use the rubber belt type car engine oil filter wrench on the tube and metal rod through the fill port. Hopefully that helps. I hope I didn't use too much force with the vice the first time that might have compromised the air tube integrity. I'm also trying to figure out how to get the plastic/delrin type ring with the rubber o ring around it that seals against the firing valve pin without damaging it. I'm thinking using the air gun connected to the Omega big air tank (I use this air gun for filling so I'm not always disconnecting air lines when filling). I'm hoping the powerful air blast will blast that sucker out of the valve body. I'll try to have it really wet with silicone oil overnight if it will help loosen it a bit. It's really stuck in there tight. Thanks for your reply.@@gardenshedgunsmith1648

[@Cisco1322]

More questions. Is it possible to put a regulator gage on the cylinder. Not just a regulator but a gage with it?

[@gardenshedgunsmith1648]

Not that I know of.

[@TheHDReleaser]

Hi. Interesting work. I have a question for you, here in Sweden, we are restricted to 10J on our rifles, by installing a valve pin, we can go back to the 57J that (bullboss) is made for, beside changing the valve pin, is there anything else needed to change? hammer spring or anything else? is just changing the valve all one needs? my .25 with 10 J is so weak it cant even penetrate a Pepsi bottle at 15 meters...

[@gardenshedgunsmith1648]

That's all that is needed. You may be able to squeeze a little more power with a stronger hammer spring though, but the biggest difference is the valve pin.

[@dutchsailor6620]

Very likely the internal transfer port will be restricted and needs to be replaced or drilled. I made one from a piece of 6 x 0.5 stainless tubing. BB .25 The barrel transfer port can be enlarged without any problems to 5mm. Check that the pellet probe is long enough and pushes the skirt of the pellet beyond the barrel transfer port.(depends on pellets/slugs used) Hammerspring tension has to be determined by using a chrono to optimize power/shotcount.

[@malcolmwatkiss881]

Hi hope you don't mind me asking put where can I get a release valve for my hatsan at44 I bought the gun second hand did not have one with it hope you can help me

[@gardenshedgunsmith1648]

Where in the world are you located?

[@Cisco1322]

Before you remove the cylinder from rifle, do you have to bleed all the air out completely in order to change cylinders to put in a full cylinder in the rifle?

[@gardenshedgunsmith1648]

No. Some people, me included actuall keep fully pressurized spare cylinders so you can just change the cylinder instead of constantly refilling the cylinder on the gun.

[@iguanagohunting4610]

Mine is too tight to break free. Was hoping you had the same problem and showed how you opened it up. I am breaking stuff and luckily havent damaged the cylinder,,,, yet.

[@gardenshedgunsmith1648]

Have you tried heating it? If there is loctite on the threads this will soften it up. It will also expand the cylinder a tiny bit which will also help. Just don't get carried away as there are plastic/rubber parts in there. Good luck.

[@joedejesus6363]

Hey Iguanago,....I had a leak in two of my Hatsan AT-44 Air tanks, I was able to remove both ends of the Air Tank. What I used was a piece of thick rubber tire tubing and two blocks of wood. I wrapped the rubber tire tubing around the Air Tank, and sandwich the Air Tank. between the two blocks of wood. I then tightened it on a vice, I used a 13 mm open end wrench on the air exhaust end, and turned it counter clockwise. If the Air Tank moves when your trying to remove it, tighten the vice a little bit tighter, being careful not to squish the Air Tank. On the Air pressure gauge side I twisted the cover off and that rotating Ring/Dust Cover turns and it twists right off, so you can access the "Fill Probe Air Port" Use a tool that's a least 1/4" in diameter and long enough to give you some leverage, and push it through the "Fill Probe Air Port". I used a "Punch" where I only had about 4 - 6 inches of leverage. Yet I was still able to remove it. I didn't see any relics of any "Loc- Tite when I removed mine. I hope this helps you out. Happy Hunting

[@shooterxchannel8102]

Liked and subscribed.👍👍😁

[@lamardaniels6625]

My hatsan bt65 .22cal was pumped all the way to 200bar, it then started to slowly leak down, to just 100 bar, it stopped leaking at 100 bar....any idea how to resolve this? Where I can pumping back up and no leaking?

[@gardenshedgunsmith1648]

The only way to be sure is to take the cylinder apart and maybe lube up all the O rings and seals with some good quality silicone grease.

[@lassesarnhult9283]

Do i need to change the spring if i go for full power valve pin and shuld i remove the regulator also. Mine gun is in 10j

[@gardenshedgunsmith1648]

Hej Lasse. Are you asking about the spring in the valve or the hammer spring? No need to change the valve spring that I know of. You can change the hammer spring but I would first just change the valve pin to the full power version. You can then adjust the hammer spring tension to get the power where you want it to balance accuracy/consistency etc. If you have a regulator fitted then it will most likely need adjusting if it is fitted to a 10j gun at the moment. I don't find the Hatsans benefit a great deal from having a regulator fitted anyway. If you are after maximum power then remove any regulator as it has to reduce the cylinder pressure to a consistent level behind the valve pin.

[@lassesarnhult9283]

@@gardenshedgunsmith1648 Thanks. Yes I was talking about the valve spring. Is there any video how to adjust hammer spring? I am new to shis with airguns so I first thinking od buying an FX but then again I think starting with a more afforable gun is the way to go. I usualy hunt wild boar and elk with a hunting rifle and a lot more bang lol. Thanks for a nice video

[@lassesarnhult9283]

I found a video how to adjust hammer spring but haven´t a clue how it should be in my case, harde or softer

[@gardenshedgunsmith1648]

@@lassesarnhult9283 The hammer spring on the Bullboss is not the easiest and most straight forward to adjust. Once you figure out how to do it though it's pretty easy. Pretty sure there are vids out there on doing it.

[@gardenshedgunsmith1648]

You will get better quality control, accuracy with a FX but if you are after more power an FX will not beat a Hatsan.

[@shooterxchannel8102]

I got 1 that is leaking in the areas that you are showing.

[@CicerocardosoSilva]

Boa. Tenho uma at44 PA ela ta com problemas na telha fica s travando me indique alguém q quebrou uma peça foi um presente do meu pai ele j faleceu me ajude