Some help please. Where am I going wrong....

[Punchsteve]

I stripped, degreased and relubed a BSA Meteor according to Hsing's tuning guide posted elsewhere on the site. New piston spring, seals, breech seals etc.

Put the rifle back together and when cocked, there is a clack clacking sound (not dissimilar to the sound of an anti beartrap on some rifles.

At first I thought I'd bodged putting the trigger back together and this was catching, but checked it and it's fine. Then I noticed shallow parallel scratches along the length of the spring and it turns out that the 'teeth' on the cocking slide that slots into the cocking slot is catching on each coil of the spring as I cock it.

The spring seems the same diameter as the original and is supposedly the 'factory' spring for it.

Anyone have any ideas? As it is starting to pee me off.

(On the plus side, the tune worked as it shoots beautifully).

[Phil Russell]

Well: instant diagnosis is that the problem is either the cocking link or the spring.
Firstly check the spring ... do you have a caliper that you can accurately measure the outside diameter with? It does not necessarily have to be accurate, just able to let you see if the new spring is a little bit wider than the original. Is the spring an easy fit into the piston? You might like to try and fit a piston sleeve if there is room.
The cocking link arms may be a little bent and so catching on the spring but my advice is to not touch them. I assume the cocking link can move smoothly in the cylinder and piston when there is no spring there.
Cheers, Phil

[Punchsteve]

Hello Phil, thanks for your reply. I do have a set of calipers somewhere, so I will dig them out and have a look. The spring slid easily into the piston on assembly and the cocking slide moved easily along the cocking slot without the spring. Will have another tinker and post back the results. Thanks for the reply.

Steve.

[I. J.]

Have you tried putting the old spring back in to see if its something post tune up thats causing the noise?
Have you also tried reversing the new spring. I know this sounds daft but I have done this previously with a noisy gun and the noise went. Spring tolerances out?

Good luck.

ATB
Ian

[Punchsteve]

Have you tried putting the old spring back in to see if its something post tune up thats causing the noise?
Have you also tried reversing the new spring. I know this sounds daft but I have done this previously with a noisy gun and the noise went. Spring tolerances out?

Good luck.

ATB
Ian

Haven't tried putting the old spring back, it was as bent as 3 bob note , but I'll try both your suggestions, tomorrow probably, as I'm not the most patient of chaps when things go wrong and the poor old Meteor is likely to end up with an unique U shaped barrel if I keep tinkering with it today.

Thanks Ian.

PS: Yes Phil, the spring was the same size

[Punchsteve]

No mate, it's a series of 'clacks' as you cock it. It seems to be the cocking arm thingy hitting each coil of the spring as it pushes the piston.

Thanks for all the suggestions everyone, will try them all out tomorrow, or tonight if I have time.

[Phil Russell]

I am returning to this discussion as I have just experienced something similar. Replaced a spring with an identical diameter size one (as far as I could see) and got a few 'clacks' at a certain point in the cocking stroke ...started around the middle. The only difference was that the new spring had 2 more coils than the old one. My theory now is that because springs expand a little as they compress, then the slight expansion in outer diameter may have been more for the longer spring as it was under more compression at that point in the cocking stroke, hence it may have caused the cocking arm to catch a little. Either that or the spring buckled slightly towards the piston slot. Replacing the old spring restored quietness! Maybe I need to make a spring guide (Osprey does not have a guide).
Hey ho, hey ho ...
Cheers, Phil

[Mike95]

I think I would first smooth off the cocking arm lugs and grease them....almost everything in the later Meteors would benefit from smoothing off. A bit of grease on the upper section of the spring might help...also make sure the piston is central to the cylinder slot. The pistons sometimes move off centre, making the lugs stick. Make sure the cocking lugs are not out of shape..they usually are. I have had to take some of the edge off lugs to get a smooth fit in some guns. Most of the pistons on the later models are oval, rather than round!

As a previous post, always possible that the new spring diameter is slightly larger than the norm. Not a square section spring I assume, or one of the Knibbs "Titanic" jobs?

I do not have a standard spring to hand to measure o/d, possibly someone else can do this?

Mike95

[Punchsteve]

Hello Mike, it was a standard 'factory' spring ordered from Chambers (round section). Tried some of the suggestions on this thread (and some sent via PM) and the noise is still there.

I'll try lightly filing the lugs next, then if that doesn't work, it can go back into the cupboard for a rainy day.

Perhaps as suggested the spring is slightly long and bowing when compressed and could do with having a link hacked off and finished. The cocking link lug can be seen to be lightly touching the spring even when the gun is not cocked.

It's a bit of a pain actually as, other than the noise when I cock it, the gun is firing much nicer after following the tuning guide.

Thank you for all the help and suggestions gents. Much appreciated.

[brownie]

Hi mate,try making your own piston sleeve.This will give the cocking lever arm something to run on during cocking.A 2ltr coke bottle is all you need or if this is to thick then use a beer can!.
ATB
Steve

[Punchsteve]

Hi mate,try making your own piston sleeve.This will give the cocking lever arm something to run on during cocking.A 2ltr coke bottle is all you need or if this is to thick then use a beer can!.
ATB
Steve

Again something to think about. Thanks Steve.

[mikewareing]

Just to throw a "cat amongst the pidgeons", I had a similar problem a few years ago, the cracking noise was at the end of the cocking stroke, this turned out to be the two piece cocking arm clicking over centre and striking the inside of the stock.
This was remidied by some chipboard edging strip on the inside of the stock to fill the gap.

Just a thought!

[ggggr]

Your inbox is full Steve. Re above post and earlier pm. The mk5 has a little piece of plastic or similar stapled on the inside of the stock. This can crumble and break (like the breech seals and piston buffers). Red Bob sent me some similar stuff and I cut a thick slice and glued it in, Only to realise that I could not get the action in the stock and I had nothing that would get in to "shave" it down. I spent half an hour heating up a bit of metal and melting the piece enough for the action to go in the stock.

[Punchsteve]

Your inbox is full Steve. Re above post and earlier pm. The mk5 has a little piece of plastic or similar stapled on the inside of the stock. This can crumble and break (like the breech seals and piston buffers). Red Bob sent me some similar stuff and I cut a thick slice and glued it in, Only to realise that I could not get the action in the stock and I had nothing that would get in to "shave" it down. I spent half an hour heating up a bit of metal and melting the piece enough for the action to go in the stock.

Thanks for the info and the PM Guy. I don't remember seeing such a piece when I had it apart, so this may well prove to be the case!

[ggggr]

A few quick thoughts here. I would actually refit your old spring and guide and see if the problem goes away. If it doesn,t then it is something else ( logic) If it is something else then you can refit your new spring and guide and look elsewhere. Check you have the little placky spacer between the two bits of the short cocking links. It should not make a difference but might. Make sure you have the shake proof washers under the front stock screws and try undoing each stock screw a bit and see if the noise goes then. Sometimes on my crappy guns, a screw being tightened all the way before the other side is fitted, can pull an action to one side. Try to undo the rear stock screw half a turn and then try it. This may give you some idea of if the arm is hitting the stock. The arm should rub on that piece in the stock. The cocking arm seemed ok with your old set up but check for burrs. I assume that you fitted the piston head and buffer washer ok with no slop? I have seen heads with a lot of play because a tap washer was used and it is not quite thick enough ( I pack it with a washing machine hose one as well ). Also if it is the circlip piston rather than the keyhole, is the circlip properly fitted with the plain washer on top of it? If all else fails, scrounge a cocking arm off here to try.