Umarex Umarex Hammer surgery

.50 Hammer leak is found.What do you bet that I can't buy this part? I can't even find a parts list to even give the broken valve (?) a correct name :(
Oh yeah, a dilly of a pickle to tear down the rifle to find the leak. I was expecting a blown o-ring that I could easily replace. Hate to send it in as shipping both ways is more than the part and o-ring cost. Never mind the labor charge.
Worst of all, this rifle is a "clover leaf" shooter at 55 yards and 3 " at 100 yards. :)
Any suggestions or suck it up?


PXL_20250209_011920930~3.jpg
 
.50 Hammer leak is found.What do you bet that I can't buy this part? I can't even find a parts list to even give the broken valve (?) a correct name :(
Oh yeah, a dilly of a pickle to tear down the rifle to find the leak. I was expecting a blown o-ring that I could easily replace. Hate to send it in as shipping both ways is more than the part and o-ring cost. Never mind the labor charge.
Worst of all, this rifle is a "clover leaf" shooter at 55 yards and 3 " at 100 yards. :)
Any suggestions or suck it up?


View attachment 537063
Wow your hammer is a impressive shooter...I would defentily fix it...I would hope that Umarex would sell you parts for it considering it is still being made..Keep us posted. Keep up the good work
 
Power can be adjusted on the hammer. You have to take bonnet off regulator and add or subtract shims. No shims, it shoots with less power and you get 4 shots. If you get a shim like the ones in regulator and add a thin shim, it will increase about 100 FPS using a 350gr. My stock hammer shot 350 gr, at 840-850. With the added shim 350gr goes 935-950 FPS.
 
Power can be adjusted on the hammer. You have to take bonnet off regulator and add or subtract shims. No shims, it shoots with less power and you get 4 shots. If you get a shim like the ones in regulator and add a thin shim, it will increase about 100 FPS using a 350gr. My stock hammer shot 350 gr, at 840-850. With the added shim 350gr goes 935-950 FPS.
@SLICKNICK By “shims” are you referring to Belleville washers? A photo would help me understand a little better. Can you post a photo of what you’re talking about?
 
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@SLICKNICK By “shims” are you referring to Belleville washers? A photo would help me understand a little better. Can you post a photo of what you’re talking about?
There's flat shims along with the washers. It's just adjusting the actual pressure the regulator allows into the shot bottle.
 
Not my listing but this is the regulator seal kit. I can’t tell you what happens if you add more because I just added 1. They are different thickness in the kit.
 
No, those are the spring shims. They need to go back how they were
The lower one in the picture is a spring shim. They're are multiple designs. I promise. I did the valve and hammer upgrades for Umarex when it originally was released. Very minor changes so not enough to really consider it a Gen II.
 
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The pressure in the shot bottle determines power output as it's essentially a dump valve design. View attachment 540078View attachment 540079
You can control pressure with shims. It’s roughly around 200psi per shim. I put mine on a gauge, and stock does not output 3000 psi. You can check pressure before mounting reg on rifle with a similar setup

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