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collierboy

collierboy

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The accuracy of my S510 started playing up all of a sudden and I managed to narrow it down to the moderator. When I took it off something could be felt and heard moving about inside, when taken apart I was quite surprised to see how complicated the device is so took a few pics rather than try to explain the gummings. The rattling turned out to be a mashed up pellet and bits which somehow got stuck half way through which was affecting the subsequent pellets flightpath and hence their accuracy. IMG_20240721_170140703_HDR.jpgIMG_20240721_170301651_HDR.jpg
 
Had this a few times
Usually on .22
Run an 7.5 - 8mm drill through cones
You probably won’t notice any difference in sound ( just as quiet ) 👍
 
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collierboy said:
It fits to the barrel by tightening a grub screw so there is no way to adjust it, Beavers idea of making the cone holes slightly bigger sounds like it might allow the pellets through without interferance.
Click to expand...
Old feller gauge in if its the body that needs alignment on the barrel .
you could also change the O rings just incase some have softened in places allowing the baffle to move off center .
 
collierboy said:
It fits to the barrel by tightening a grub screw so there is no way to adjust it, Beavers idea of making the cone holes slightly bigger sounds like it might allow the pellets through without interferance.
Click to expand...
Hello, Ok , well looking at those internal shroud parts i would scrap them and replace with hair curlers and felt, if there is very slight play with the barrel fit i have used a coke can as a shim
 
collierboy said:
It fits to the barrel by tightening a grub screw so there is no way to adjust it, Beavers idea of making the cone holes slightly bigger sounds like it might allow the pellets through without interferance.
Click to expand...
I had a PCP that went from hero to zero when a silencer was fitted. I found the problem by examining the silencer exit hole with a 10x mag glass and saw faint grey splashes around the inside. After drilling the hole out a 2mm drill bigger, the problem disappeared.
 
Ratman72 said:
Hello, Ok , well looking at those internal shroud parts i would scrap them and replace with hair curlers and felt, if there is very slight play with the barrel fit i have used a coke can as a shim
Click to expand...
And if you add penny washers as baffles, face the breech facing side with 2 or 3mm sticky backed felt. Make the felt holes slightly larger than the washer holes so you don’t get stray fibers across the hole.
 
Ratman72 said:
Hello, Ok , well looking at those internal shroud parts i would scrap them and replace with hair curlers and felt, if there is very slight play with the barrel fit i have used a coke can as a shim
Click to expand...
A bit too drastic for me Ratman but I think making the cone holes slightly bigger is worth a try because when I tried the completely empty mod tube on the gun the accuracy returned, it was just a bit noisier that's all. The mod itself is a tight fit on the barrel before tightening the grub screw, not even room for a fag paper.
 
Bit of an update, after removing the obstruction ( mashed pellet ) then slightly enlarging the cone/venturi holes with a file the rifle is now back to grouping well, even the exact heavies in 4.51 are much better ( the 2023 tin that is, not the 2022 one which still produced a lot of fliers )
IMG_20240724_190129830.jpg
 
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