Air Arms S400F Carbine .177

[RichieRich612]

... unless the bad loading is due to ill fitting brassware .

Yes the brass should not be loctited into the body. Thought you were going to free that off?

It's not coming out
Held over the cooker hob for a good few minutes and tried to tap it out using a wooden spoon handle and nothing!
I did manage to free some excess loctite off the inside and on the barrel though.
Turning out to be a real pain in the bottom this 400f

[TenMetrePeter]

I like those chefs brûlée torches. Tiny little pointy flame. Or soldering iron direct on the brass.
If its green loctite it can be heat resisting.

[RichieRich612]

I like those chefs brûlée torches. Tiny little pointy flame. Or soldering iron direct on the brass.
If its green loctite it can be heat resisting.

Don't know what kind of loctite it was but heating it and tapping it back towards the bolt end and fitting the new breech seal seems to have solved the problem.
I don't think the brass barrel housing was in the correct position.
Now I've got an extremely stiff cocking bolt
On the up-side it's shooting a little quieter now just the stiff cocking problem.
Richard

[Jammy13]

Richard,
use a heat gun on it's lowest setting. You don't have to heat it very, very hot. Heat it enough so you can just bear to touch it, same for anything you are heating to loosen on the gun. I find 2 applications of heat works best with a minute between them. This will allow the heat to soak in.


You do need to remove the barrel seal holder. If you don't there is a chance you will Loctite it in place.


Keith

[Jammy13]

Richard,
as Peter suggests you must Loctite the brass to the barrel out of place.

A stiff bolt can be caused by not tightening the bolt housing evenly when rebuilding because it can cause a twist in the bolt housing. Take it off and check to see if the bolt is then free travelling. If so refit the housing.

A theory I have as to why the barrel should become loose at the brass seal housing is this. A lot of people pick up the gun by the barrel when it's stood upright. This can put weight on the Loctite and overtime it fails. There's not much on that joint when it leaves the factory.

Another reason it can come loose is trying to force load a .22 pellet into a .177 barrel. I know this cause I did it!!!!! I didn't use a lot of force. Since then I've marked all my .177 magazines so I won't make the same mistake again.

Keith

[RichieRich612]

Don't think I aligned both sections of the action perfectly, that would explain the stiff cocking. What's the best way to perfectly align everything on assembly please?
That's enough for today, back at it tomorrow after work
Richie

[tonyc]

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

I'm not sure when the block was changed but I thought it was all the f models - they are now specific to the .177 so the pellets go straight in.

If the stiffness is at the end of the cocking stroke could the probe have been bent/damaged by previous forced loading?

[RichieRich612]

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

I'm not sure when the block was changed but I thought it was all the f models - they are now specific to the .177 so the pellets go straight in.

If the stiffness is at the end of the cocking stroke could the probe have been bent/damaged by previous forced loading?

No my friend it's stiff all the way! Must be dragging the cocking dog along the inside of the block due to not being perfectly aligned on assembly. Bolt is still straight, already checked that.
Richard
P.s it's only stiff when assembled, runs really smooth when the bolt housing is free and off the rifle.

[Jammy13]

Richard,
as Tonyc said the probe end may be damaged but I doubt that.

Make sure the figure of `8` on the barrel is removed before refitting it back together. Loosen off the 6 bolts a full turn and check the bolt

movement. If it is free running then retighten the bolts diagonally a bit at a time keeping the mating gap along the sides equal.

Keep checking the bolt and if it goes stiff then you know you are twisting it's housing so back off that last bolt and tighten diagonally or opposite to it.

Bear in mind you are tightening into an alloy with steel so don't over do it.

You did carefully fit the transfer port O ring and were careful to ensure it stayed in place when offering the top to the bottom ?


Keith

[RichieRich612]

Richard,
as Tonyc said the probe end may be damaged but I doubt that.

Make sure the figure of `8` on the barrel is removed before refitting it back together. Loosen off the 6 bolts a full turn and check the bolt

movement. If it is free running then retighten the bolts diagonally a bit at a time keeping the mating gap along the sides equal.

Keep checking the bolt and if it goes stiff then you know you are twisting it's housing so back off that last bolt and tighten diagonally or opposite to it.

Bear in mind you are tightening into an alloy with steel so don't over do it.

You did carefully fit the transfer port O ring and were careful to ensure it stayed in place when offering the top to the bottom ?


Keith

Yes Keith I always make sure the transfer port o ring is always in line.
I'll try again tomorrow as have to be up early for work, I'm sure it's the alignment that's causing the issue.
Thanks very much for the information.

Richie