Air Arms S400F Carbine .177

[RichieRich612]

Bit of trouble with the s400f guys and I haven't a clue how to remedy it even if it's possible at all.
Loading the pellet is the issue, feels as if the pellet once pushed past the breech seal wants to divebomb into the transfer port.
I've never had this issue before with any Air Arms Rifle.
If loading the pellet slow it really does not want to go in the breech unless way too much force is applied thus damaging the pellet and accuracy.
What i'd really like to do is remove the internal brass breech section from the breech housing and inspect it for any imperfections which may be causing this.
The transfer port is standard and has not been enlarged at all.
It's really boggling me as it's a lovely rifle and not being used as much as it deserves due to this loading problem.

[Roger5]

What pellet are you using? You will notice that as you close the bolt on the .177 the pellet is pushed up into the breech, rowan engineering get round this by making a small piece of curved metal that fits in the tray, this helps to keep the pellet level as it accesses the breech, it's all to do with the fact that all the bolt housings were built as .22 hope that helps. Rog

[RichieRich612]

What pellet are you using? You will notice that as you close the bolt on the .177 the pellet is pushed up into the breech, rowan engineering get round this by making a small piece of curved metal that fits in the tray, this helps to keep the pellet level as it accesses the breech, it's all to do with the fact that all the bolt housings were built as .22 hope that helps. Rog

Yes I see what you're saying but why aren't they made like the Mpr anymore then? Loading tray is perfectly aligned with the breech and pellets slide in effortlessly.
The pellets I use are Jsb Exacts and Jsb Heavies.
So it's an aftermarket piece I need then to shoot a £600 pound rifle properly and accurately?!
Not very good is it.

[Roger5]

The MPR was only available as .177 and uses a CZ barrel, the only time I have had the type of problem you have, is when using short pellets, and that was when using a rowan mag kit, they dropped into the tray, and the probe squashed them, I don't use short pellets anymore, just stick to AADF 4.52. Is this a new or 2nd hand rifle?. Rog

[Roger5]

The MPR was only available as .177 and uses a CZ barrel, the only time I have had the type of problem you have, is when using short pellets, and that was when using a rowan mag kit, they dropped into the tray, and the probe squashed them, I don't use short pellets anymore, just stick to AADF 4.52. Is this a new or 2nd hand rifle?. Rog

A new barrel seal holder S402b might be the way to go, Julian will sort you out

[RichieRich612]

The MPR was only available as .177 and uses a CZ barrel, the only time I have had the type of problem you have, is when using short pellets, and that was when using a rowan mag kit, they dropped into the tray, and the probe squashed them, I don't use short pellets anymore, just stick to AADF 4.52. Is this a new or 2nd hand rifle?. Rog

I have an Mpr and will never let that go!
Yes it's a second hand rifle but only a year old.
The Jsb Heavies aren't a short pellet, slightly longer than both aadf and Exacts.
How would a new breech holder improve things may I ask?
I've tried to remove the breech housing by undoing the grub screw beneath it but it doesn't want to come out at all.
Is it held in place with loctite?
Richard

[Roger5]

Has it always been like this? Or just started to happen, the barrel seal holder is normally loctited to the barrel, and should come out with it, some times they stay in the bolt housing and can be difficult to remove, I only suggested a new one in case the old one had some damage .Rog

[RichieRich612]

Has it always been like this? Or just started to happen, the barrel seal holder is normally loctited to the barrel, and should come out with it, some times they stay in the bolt housing and can be difficult to remove, I only suggested a new one in case the old one had some damage .Rog

Yes it's always been like this to be honest, I've taken it all apart to see if there's anything obvious causing the roughness and didn't find anything.
The seal housing does indeed stay in the breech block when removing the barrel.
If it's held in place using loctite then it shouldn't be too difficult to remove with heat.
How would you suggest removing it?
Richard

[Roger5]

I've never myself had this problem, they have always come out with the barrel (just lucky I guess) but I think a bit of heat is the way to go, and try to push from the probe side, there is probably someone on here who knows a bit more about this. Rog

[TenMetrePeter]

Maybe it has slipped back and out of position leaving a gap. Removing and refitting the brassware may do it. Heat and loctite required.