S400 Breech seal still leaks

[Simonsays]

Following on from my earlier thread http://www.airgunbbs.com/showthread....urus-out-there, I have now got my new (to me) S400 up to scratch thanks to this forum (thanks again Chris, UKNeil et all). WIth the guidance it was a doddle.

Before stripping I noticed some blow back from the breech when firing so I replaced the breech seal.

Despite all being good in terms of performance, I am still getting the same amount of blow back through the new breech seal. Is this normal? If not, is there a tighter alternative or is it a new probe required?

As ever, I would appreciate words of wisdom.

[u.k.neil]

Pellet probe 'O' ring seal mate, inside the brass bush that the probe goes in to.

Neil

[oliver13]

Pellet probe 'O' ring seal mate, inside the brass bush that the probe goes in to.

Neil

What he said.
It's really a consumable & will wear eventually, but stuffing pellets in backwards or similar can knacker them pretty quick too.
Here's a handy S400 exploded diagram on Chamber's, I don't know if you've seen it, you want part no. OR056, https://www.gunspares.co.uk/shopdisp...=24238&Search=

If you can work out the size they will be a lot cheaper from a factors, & you might as well get a few spares as well.

[Simonsays]

What he said.
It's really a consumable & will wear eventually, but stuffing pellets in backwards or similar can knacker them pretty quick too.
Here's a handy S400 exploded diagram on Chamber's, I don't know if you've seen it, you want part no. OR056, https://www.gunspares.co.uk/shopdisp...=24238&Search=

If you can work out the size they will be a lot cheaper from a factors, & you might as well get a few spares as well.

Thanks very much Oliver, but I am confused here. OR57 is the internal barrel breech seal. Where does OR 56 reside please. Didnt spot it in the strip down. Note that I feel the air escaping from around the probe tip/loading port and hence I assume, OR56, not the bolt end. I have already changed this seal.

[u.k.neil]

Thanks very much Oliver, but I am confused here. OR57 is the internal barrel breech seal. Where does OR 56 reside please. Didnt spot it in the strip down. Note that I feel the air escaping from around the probe tip/loading port and hence I assume, OR56, not the bolt end. I have already changed this seal.

OR 056 is the one I am talking about mate. If it goes too bad it can actually lift the bolt.


Neil

[Simonsays]

OR 056 is the one I am talking about mate. If it goes too bad it can actually lift the bolt.


Neil

OK, gotcha. Thanks, I'll change this out when I get the new firing valve and main spring to go in.

[gb68]

Thanks very much Oliver, but I am confused here. OR57 is the internal barrel breech seal. Where does OR 56 reside please. Didnt spot it in the strip down. Note that I feel the air escaping from around the probe tip/loading port and hence I assume, OR56, not the bolt end. I have already changed this seal.

One is a .177 and t'other a .22 seal

[Simonsays]

Pellet probe 'O' ring seal mate, inside the brass bush that the probe goes in to.

Neil

Thanks Neil. Think I missed OR56. I have a seal set and wondered about this obe. It resides inside the bolt housing I assume?

I changed the seal OR 57 but I still feel the air escaping from around the probe tip in the breech.