tuners, Q about the bsa meteor

[Silverfox1307]

I think you are confusing T20's SMK B2 tune with another one on the BSA Meteor.

Bowkett got the BSA Meteor up to 12 ft/lbs in .177 (!) but it was a nasty rifle to shoot (according to eye witnesses) heavily sprung and recoiled harshly.

A well run-in one .22 one in standard fettle and the right pellet will give a good 10 ft/lbs, the .177 about 8.5 ft/lbs.

Jon Budd has a thread on his one somewhere that is doing quite well energy-wise and is pleasant to shoot.

I am converting one of mine to a HW 26mm piston seal, which should give a bit more swept volume and a bit more efficiency. The bore x stroke is smaller than a B2, I've got it written down somewhere... But the potential is for 10 ft/lbs in .22 with a standard spring and transfer port... I know this because my old 1973 model does this, no mods just see alot of shooting and a bit of Dri-Slide. I think there are leakage or 'O'-ring tightness issues with some Meteors, they are made from rolled sheet steel and the compression chambers are rarely truly circular. A parachute seal should seal much better as it is more flexible and forgiving than the 'O' ring... the old leather-seal ones would be quite powerful when run in so I believe. Jon Budd found the piston is too light (another piece of rolled and welded steel sheet) so putting a steel top-hat in might help with power.

I think you can get them going NICELY up to about 10 in .177 and maybe a tad over 11 in .22.

T20s sleeving-down of the SMK B2 port made the little chinese rifle jump from 8.5 to 12 ft/lbs; however there is no similar trick with the BSA Meteor.

I like the sound of doing this conversion to HW piston seal from o-ring and would like to have a go on my Mk3 Meteor, what needs to be done, does the piston head need new mods or a different type of piston head to get it to fit? My piston head measures 25mm so would the 26mm seal be too tight in the chamber? Intreaged!

[Shed tuner]

http://www.airgunbbs.com/showthread....wer-BSA-meteor

If a 26mm is too tight in yours, a 25mm would work, or an LGV/U 25.3mm

[Silverfox1307]

http://www.airgunbbs.com/showthread....wer-BSA-meteor

If a 26mm is too tight in yours, a 25mm would work, or an LGV/U 25.3mm

Thanks for the link Jon, what I thought was a simple fix is looking to be a bigger operation than I thought as I don't have the machining equipment in my garden shed to perform such a task! but I may just buy a HW77 seal (25.5mm on JKI) to measure up and see what needs to be achieved, I have both a threaded and keyhole piston head so one may suit better, the threaded one gives enough thread to be able to add a few washers for weight.

[greenwayjames]

One of the most important features of the 12 ft/lbs Meteor conversions the Bowket used to do was the improved barrel hinge pin and lock up. He bored out the breech block and one of the jaws, made an oversize bolt and threaded it into the other breech jaw. It was then locked in place by a scew to prevent the bolt rotating and working like a cam to alter poi. I had one which I didnt mess with but just shot it and the recoil and accuracy were perfectly adequate for bunny popping out to the distances my FWB and HW35 were used at. I was told that once the piston was taken out of the cylinder it was , so I didnt

[Silverfox1307]

Thanks for the link Jon, what I thought was a simple fix is looking to be a bigger operation than I thought as I don't have the machining equipment in my garden shed to perform such a task! but I may just buy a HW77 seal (25.5mm on JKI) to measure up and see what needs to be achieved, I have both a threaded and keyhole piston head so one may suit better, the threaded one gives enough thread to be able to add a few washers for weight.

Jon, see link below, would this be the answer (for those of us who dont have the machining equipment) to convert to a Meteor to HW type seal?

http://www.vortekproducts.com/oursto...?product_id=95

[Shed tuner]

Jon, see link below, would this be the answer (for those of us who dont have the machining equipment) to convert to a Meteor to HW type seal?

http://www.vortekproducts.com/oursto...?product_id=95

it's basically there, but you need to somehow screw it to the piston head...

[Silverfox1307]

it's basically there, but you need to somehow screw it to the piston head...

Is that not what the countersunk bolt as seen in the image would be for and using a washer and locknut inside the piston in similar fashion to the threaded type of meteor piston head?

[Shed tuner]

Is that not what the countersunk bolt as seen in the image would be for and using a washer and locknut inside the piston in similar fashion to the threaded type of meteor piston head?

Could do yeah, but a washer and locknut might be a bit sloppy. Maybe adding a bush to where the bolt passes through the piston would address that. Or drill out the bolt hole to take a larger OD bolt.

I guess I worry slightly that the bolt is quite skinny... in a Gamo, it would be screwed straight into the piston, so no movement = not a problem, but in the Meteor it would be floating around, and subject to some forces that it might not be able to withstand - hence the bush idea. In fact, a threaded bush would be perfect - but a bigger bolt would be easier.

[Airsporter1st]

In 1971 my dad's mate said he shot a rabbit dead at 178 paces with a BSA Meteor, open sights, firing a Champion pellet.

It was later discovered to be an Exaggeration - the story, not the airgun.

That could be less than 30 yds if he was pacing with the heel of the fromt foot touching the toe of the back one!

[Silverfox1307]

Could do yeah, but a washer and locknut might be a bit sloppy. Maybe adding a bush to where the bolt passes through the piston would address that. Or drill out the bolt hole to take a larger OD bolt.

I guess I worry slightly that the bolt is quite skinny... in a Gamo, it would be screwed straight into the piston, so no movement = not a problem, but in the Meteor it would be floating around, and subject to some forces that it might not be able to withstand - hence the bush idea. In fact, a threaded bush would be perfect - but a bigger bolt would be easier.

I see where you are coming from and agree with the larger bolt idea, this would possibly be more achievable for myself with only basic tools, fashioning a bush might be a bit out of my league! - I see that there is a Uk outlet for this part, I just might just send for it for the sake of a few quid and see how I get on - I'll let you know.

[TonyL]

. I was told that once the piston was taken out of the cylinder it was , so I didnt

Blimey!

[Meno]

The BSA tuned is capable of delivering in excess of 12ft/lb even in .177 but needs some machining and other work to obtain it

[Silverfox1307]

Could do yeah, but a washer and locknut might be a bit sloppy. Maybe adding a bush to where the bolt passes through the piston would address that. Or drill out the bolt hole to take a larger OD bolt.

I guess I worry slightly that the bolt is quite skinny... in a Gamo, it would be screwed straight into the piston, so no movement = not a problem, but in the Meteor it would be floating around, and subject to some forces that it might not be able to withstand - hence the bush idea. In fact, a threaded bush would be perfect - but a bigger bolt would be easier.

I now have the part and seal in 25mm and fitted it to the piston but I fear it may be slightly to small as when I push it up in the chamber it slides quite easily even with my finger over the transfer port, perhaps I should have ordered the 26mm and sized it to the chamber.

[Shed tuner]

I now have the part and seal in 25mm and fitted it to the piston but I fear it may be slightly to small as when I push it up in the chamber it slides quite easily even with my finger over the transfer port, perhaps I should have ordered the 26mm and sized it to the chamber.

yes, as I suggested above
You could try the lgu seal which is about 25.3/4mm. My guess is the meteor bore is 1" 25.4mm, so just go with 26 as I did... no sizing needed.

[Silverfox1307]

yes, as I suggested above
You could try the lgu seal which is about 25.3/4mm. My guess is the meteor bore is 1" 25.4mm, so just go with 26 as I did... no sizing needed.

point taken!
25mm being returned to be replaced with 26mm next week.