2 mercury's tuning test beds

[wrowmon 1]

ok have two bsa mercury's have the gear to tune and test.tool's,chorno,and time.

 

will do the normal spring,washer,weights,porting,lubs .

 

but have you lot any ideas will do it with all the bits i have and will only use eley wasp 5.6 mm as they are best for older bsa's

 

at mo one kicking out 558 fps with 14.64gr wasp.

other 577fps with same pellet..

 

any one with an idea they wanted testing...

[wrowmon 1]

ok am tuning this gun up for countrykid come on ..he is the future of our sport..

[Countrykid 1]

Thanks again

In the future I might also take over the world

Callum.

[davyt63 1,845]

hi buddy

are you asking what fps you need it to be @, for 11.5ft/lb

 

or are you asking how its done tuning!

 

regards

 

davy

[wrowmon 1]

country kid not the best to say...try i will work with whales and save the planet...not bleeding control it...but the gun is yours even if i have to travel down to drop it off...just checked i have 13 air rifles here...

[wrowmon 1]

davy am pretty good at tuning but just asking for other ideas..i prefer smooth 10.5 than loose my teeth 11

[Countrykid 1]

13?!?!

Haha thanks again

Regards

Callum

[davyt63 1,845]

davy am pretty good at tuning but just asking for other ideas..i prefer smooth 10.5 than loose my teeth 11

 

 

ok buddy

im not a springer person but andyfr68 may have some more ideas! for ya

regards

 

davy

[Marksman 934]

I think you've more or less covered the basics tbh mate.....

 

you could try a total degrease and finely polishing the internals to make them "extra smooth" to create the least resistance also ensuring a nice tight fitting seal in the chamber.

It's more consistency you want than power mate, like you said....a consistant 10.5 is better than an all over the place 11

 

Darryl

[ulverston moocher 60]

Has any body sorted out a scope for country kid yet?

[andyfr1968 772]

Hi, mate.

 

(Davy!!) Like Markman's said, a good clean and polish session never goes amiss but don't go mad with the polishing. It's one thing to clean off any rough edges, another to widen the tolerances so that the piston slaps around in the cylinder when you fire...

 

A couple of points to watch for on those are, firstly the piston seal's a rubber 'O' ring and can be very easily damaged when slideing the piston back into the cylinder past the end of the cocking linkages slot. They are always sharp on the inside and want to shave a bit off the seal as it slides past. Useing a small round file, remove the sharp edge but still be careful! If you can find some, lube the seal with a little smear of silicon grease. Don't use normal grease or oil anywhere near the compression chamber as it will ignite under compression, silicon grease won't.

 

Also the barrel lock-up on those does not age well, poor quality steel and poor design. The early ones just had a pin to hold the barrel and let it pivot and these wear and allow a little movement even when the barrel's shut. Replace this pin and grease with molly. Also while it's in bits, replace the spring behind the barrel catch.

 

It sounds like you're clued up, mate, so all the best with it!

 

Cheers.

Edited February 22, 2010 by andyfr1968

[wrowmon 1]

hi andy have done most of the spings and the barrel pins have been modded so no wobble,am in the process of drilling the piston head and adding some lead to it to see if this helps the performance will post picks of work in due course...am sure the additional wieght will help and it will not shake loose due to the pistons travel as this mod has worked on a airsporter..

 

countrykids mercury is on hold at mo his mum was a bit worried that someone offered him a free air rifle..but it's here to be tuned..

[andyfr1968 772]

Hi, mate.

 

I've heared of that mod on Aisporters and Mercuys but I've never tried it.

 

One thing I have remembered is the piston heads on the .177 rifles allows for a greater swept volume to counter the fact that the smaller caliber is less efficient....

 

Cheers.

[wrowmon 1]

Hi, mate.

 

I've heared of that mod on Aisporters and Mercuys but I've never tried it.

 

One thing I have remembered is the piston heads on the .177 rifles allows for a greater swept volume to counter the fact that the smaller caliber is less efficient....

 

Cheers.

had not heard of that.....returns from loft with 177 airsporter...maybe thats the volume mod trobb offered.thanks will try that one too..

have fitted a ptfe type seal to one bsa today(do nites sometimes)..588fps but a bit of brunt off lube first few so will put a few hundred thru it and see what happens..

Edited February 23, 2010 by wrowmon

[andyfr1968 772]

I'm going back to the mid 's when I used to fix the bloody things for a living but I'm sure I'm right on that one.

 

It was a very common mod on those back then (a-hem..), so it may well have already been done. It is a nice way to make the .22's shoot a little better, they rarely gave much more than 10ft-lbs as standard.

 

Is it the standard or the 'S'? Lovely walnut stocks on the S.

 

Cheers.