Bowkett Meteor (stripped, pics and questions)

[lightning22]

Hello,

The Story

In the mid 80's I was unleashed on an unsuspecting world with a BSA Meteor 'S' in Mk5 flavour. Over the next couple of years it was in pieces more often I care to remember, being polished and relubricated...... it was even 'treated' to an OX spring.

Had I had the money it would have been sent to John Bowkett for his 12ftlb conversion which IIRC cost £25 plus a couple of quid for postage. It was eventually chopped in for an Airsporter and the conversion never happened, though I've looked for one ever since........

Then one came up on here without a stock and it was mine!

As is typical I shot it a couple of times, winced at the recoil and put it away as my FAC came through. I bit the bullet the other day, stuck a scope on it and took it to the club. It was bloody horrible! I haven't worried about breaking a scope for ages.

Closer inspection revealed a breech seal made of cheese so it went away again and I ordered the bits.

Today I dropped my Spitfire off with the man himself and dragged the old Meteor up for him to have a peer at for old times sake. Thus galvanised into action, I've stripped it down tonight to have a look-see.

Pictures

.... and this is what I found..... the main bits, given that this is a small rifle with a reputation for doing 12ftlbs in .177 I was expecting a bit of preload, I wasn't wrong. A notched delrin bar and a sash cramp took care of the safety side of things and a rather odd looking spring and guide arrangement came out. At first I thought it was a square section spring, but it was just a thick layer of moly giving the impression of round being square. I had expected one of the custom guides that John used to sell, instead a section of spring has been wound into the spring on a standard guide, locking the spring to the guide. It can't twang as there isn't much chance of the guide touching the spring.

Next out was the piston which has also been heavily modified with a new head, a thin plastic buffer and a square section seal. The piston is retained in the piston by a large threaded bar, which together with the ring that preloads the spring acts as a substantial piston weight.

Inside the cylinder there is evidence of cross-hatch honing and what looks like a 45 deg angle applied to the transfer port.

The spring spec on the beastie is as follows......

Overall length = 240mm

No. of coils = 30

Inner diameter = 12.8mm - 0.5"

Outer diameter = 19mm - 0.748"

Wire diameter = 3mm - 0.118"

Questions

John reckons he's done 'hundreds' of these, anyone else out there got one?

Any idea where the piston ring originates from? Does it look familiar to anyone?

I will ask John, but thought I would share this here and hope that someone might know.

Rich

[Hsing-ee]

At last the secrets of the 12 megaton Meteor! Thanks for posting this always wanted to know how it was done.

There were also some Airsporters that he did which had very short springs and almost no recoil.

[I. J.]

Thanks for that interesting info.

ATB
Ian

[Paddy_SP]

I look forward to trying out the finished article!

[lightning22]

At last the secrets of the 12 megaton Meteor! Thanks for posting this always wanted to know how it was done.

There were also some Airsporters that he did which had very short springs and almost no recoil.

You'll be glad to know it has a threaded breech bolt..

[Garvin]

Fascinating. Thanks.

[lightning22]

The spring spec on this is as follows......

Overall length = 240mm

Inner diameter = 12.8mm - 0.5"

Outer diameter = 19mm - 0.748"

Wire diameter = 3mm - 0.118"

I'm guessing that the nearest thing to this off the shelf would be a Titan XS.

Rich

[Hsing-ee]

The spring spec on this is as follows......

Overall length = 240mm

Inner diameter = 12.8mm - 0.5"

Outer diameter = 19mm - 0.748"

Wire diameter = 3mm - 0.118"

I'm guessing that the nearest thing to this off the shelf would be a Titan XS.

Rich

POK! could wind one up from those specs I guess.

[lightning22]

POK! could wind one up from those specs I guess.

I'm sure he could! I thought putting it here would be safer than writing it down somewhere and losing the paper.

Rich

[lightning22]

POK! could wind one up from those specs I guess.

POK! isn't doing springs again at the moment..

[Tenuc]

Thanks Rich for revealing the mysteries of the JB Meteor tune, it's an excellent guide.

My first new gun, some 50 years or so ago, was a MkI Meteor in .22 calibre. I used it as my main hunting gun for about 10 years, before moving on to a HW35. I re-furbed it 10 years later, and both my boys learned to shoot with it, until they moved on to bigger and better things.

I retired 18 months ago, and with nothing much to do, got the old meteor out of the wardrobe. It was in a sorry state, with erratic cocking and little power, so I fitted a new mainspring, washer and seal.

When I chrono'd the gun after it had settled in, I found it was pushing out 11.4FPE with Daystate FT pellets!!! I think it's amazing that a gun of that age, with such a small swept volume can deliver this result???

I hope you have fun with yours, when its back together again.

[lightning22]

That's excellent power for a Meteor!

I spoke to John the other day, the seals were made specially to his spec and are no longer available

The good news is that you can always use the std seal.

Rich

[Hsing-ee]

When I chrono'd the gun after it had settled in, I found it was pushing out 11.4FPE with Daystate FT pellets!!! I think it's amazing that a gun of that age, with such a small swept volume can deliver this result???

That is very high power for a Meteor, mine does about 9.5 ft/lbs and seems to be happy with the standard spring. The sear arrangement doesnt look like one that would respond well to increased mainspring pressure.

One thing about the Meteor is that its transfer port is very short and has a very small volume. Perhaps this is the secret to its efficiency?

[Tenuc]

That is very high power for a Meteor, mine does about 9.5 ft/lbs and seems to be happy with the standard spring. The sear arrangement doesnt look like one that would respond well to increased mainspring pressure.

One thing about the Meteor is that its transfer port is very short and has a very small volume. Perhaps this is the secret to its efficiency?

The spring I used was a Titan from J Knibbs, and there is a thick steel washer in the breach end of the piston. The piston seal is home-made from some shoe leather, soaked for a week in Neatsfoot oil. It had a new breach seal and I lubed the compression chamber and spring with a 50/50 mix of LT2 moly grease and lithium grease, liberally applied.

I've found old springers with leather washers like to run 'wet', with a nice puff of smoke lingering in the barrel after the shot, although not too much or you get detonation and poor accuracy. I also put 2 drops of motor oil down the transfer port after each tim of pellets, and leave the gun standing barrel up over-night.

As you mentioned, the mk1 trigger was never the best bit of design, but it is no worse since the rebuild than it ever was - heavy but predictable. I can still get 1" groups with it at 30yd on a good day!

[Hsing-ee]

This approach to tuning seems to rely on spring power. What about the dishing of the transfer port, would that not create lost volume?