I bought this little gem about 12 months ago, and I absolutely love it. Well made, yet simple and effective.
As bought it shot around 11.2 ft.lbs but only gave around 10 shots from an 8 gramm sparklets bulb, and .... it had a slow leak. It would leak out , if left to stand in about 1 and a half hours.
After trying 4 different types of valve seal, without success, I eventualy discovered that the brass valve seat had a nick in it. As the valve body is not removeable I had a choice, ... live with it or de-solder the valve block and repair. I decided on the latter.
So after grinding out the spot welds on the barrel bands and lifting the barrel to remove the transfer tube, then removing the valve block and re-facing the valve seat on my small lathe ,I then had the daunting task of re-soldering the block back into the gas tube. I was very unsure if I could ever be certain that I had a continuous bead of solder around the valve block, without any gaps in the solder through which the co2 could escape. After 2 atempts I succeeded.
Now, how to re-attach the barrel bands, as I don`t have access to spot welding or tig welding. What I did was to drill 2 holes in each side of the clamps,( one either side of each spot weld ), so 8 in all, then clamp the barrel in position on the gas tube and drill through all 8 holes in the barrel bands into the gas tube.
Hope you are still with me... Then I tapped the 8 holes in the gas tube m3 and secured the barrel to the gas tube with 8 countersunk screws. Those at the front ( into the gas chamber ) I sealed with threadlock. The rear ones I did not need to seal as they are to the rear of the valve block.
This repair was successful and not too unsightly. The rifle holds gas fine now with my ptfe valve seal.
Next job was to fit different valve and hammer springs to give me more shots per fill. It now shoots at 9 and a half ft.lbs and gives 18-20 shots per bulb.
Very little is known about this rifle here in the U.K. , indeed I have never seen another 352 in all my 63 years.
What are your thoughts on this model.???
P.S Can`t figure out how to upload pics.
I have to admire your persistence, and skills to make this re-seal work that way. I've never worked on a 352, but other CO2 Benji's of that era have a snap ring that retains the valve assembly, and you need to get the ultra-long nose, special benjamin pliers to get it out. Its shown on the parts diagram, but no mention of the pliers. Then everything just falls out the front of the tube. Benjamin was always concerned that people be able to service their own guns, so I'm having a hard time seeing how this model would be different and have no potential for servicing. Sounds like it worked out for the best, however, with more shots from those little powerlets.
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