Airsporter/Mercury spring clamp

[LESS THAN FORTUITOUS KENNETH]

I put the trigger unit in a vice, padded with 2 bits of wood. Then just unscrew the tube. When putting back, cut a tennis ball in half and put it over the end of the tube when refitting so that the jaws don't rip into your palm. Works for me.

[Benelli B76]

Yup! - the brute force method!
Problem is, I probably don't have the strength I had when I last did this.
The other problem being that the fine pitch of the thread makes it easy to cross thread - if you are not careful enough!
I used to scribe a very small fine line on the interface of the trigger block and the air cylinder tube (usually out of sight below the woodwork so is hidden when the stock is refitted) - so that I didn't have to guess the re-alignment - anyone else done that?
I think I will have to look at making up something on the lines of the op, using plywood, built up is a splendid idea!
(could anyone post up any pictures of a suitable clamp? Mick - you seem pretty good at this type of thing!)

ASM

Simple little job,I just cut 5 pieces of plywood, 2 plain squares and 3 with cut out to accept the shape of the trigger unit. The made up block now fits squarely to the sash clamp and the threads match. No struggling to bring the parts together by brute force, just wind up the acme thread on the clamp. Pic of block with square side not fitted and finished Mercury.

Baz

[Airsporterman]

Simple little job,I just cut 5 pieces of plywood, 2 plain squares and 3 with cut out to accept the shape of the trigger unit. The made up block now fits squarely to the sash clamp and the threads match. No struggling to bring the parts together by brute force, just wind up the acme thread on the clamp. Pic of block with square side not fitted and finished Mercury.

Baz

Brilliant - thanks Baz!

ASM

[junglie]

Simple little job,I just cut 5 pieces of plywood, 2 plain squares and 3 with cut out to accept the shape of the trigger unit. The made up block now fits squarely to the sash clamp and the threads match. No struggling to bring the parts together by brute force, just wind up the acme thread on the clamp. Pic of block with square side not fitted and finished Mercury.

Baz

God I wish this thread had been a few weeks ago when I had to pull my challenger apart to replace the buffer washer. I use the clamping the trigger block in the vice method but was in the middle of a man-flu bout & weak as a kitten. Even pushing against the wall with the muzzle on a plywood board on my chest it took a record 8 attempts to get the thread started & it back together. Would love to see the original rig bsa used to use to put them together too, but that pic will do for me to cobble something to fit my compressor for next time. 1st test shot was 666fps with hobbys as a little lube burned off then settled down to a healthy 11.5ft/lbs But it gave me a welcome laugh as it was indeed a "Devil" of a job!

[SRV1]

After years of working on these, now at 70 have not got the physical strength to hold the weird back end of these straight when fitting a strong spring. Today started making a custom socket for the action to fit in my sash clamp, should have done it years ago. I am making mine out of plywood, and thought for a laugh would ask guys on here what they had made to do this job.

Hi Benelli,

If you want some photos of the arrangement I have made, just ask......

[TonyL]

Simple little job,I just cut 5 pieces of plywood, 2 plain squares and 3 with cut out to accept the shape of the trigger unit. The made up block now fits squarely to the sash clamp and the threads match. No struggling to bring the parts together by brute force, just wind up the acme thread on the clamp. Pic of block with square side not fitted and finished Mercury.

Baz

Excellent, Baz.

The next time I have to work on one of these (I don't own one these days), I think this is certainly the way forward.

[derekj]

God I wish this thread had been a few weeks ago when I had to pull my challenger apart to replace the buffer washer. I use the clamping the trigger block in the vice method but was in the middle of a man-flu bout & weak as a kitten. Even pushing against the wall with the muzzle on a plywood board on my chest it took a record 8 attempts to get the thread started & it back together. Would love to see the original rig bsa used to use to put them together too, but that pic will do for me to cobble something to fit my compressor for next time. 1st test shot was 666fps with hobbys as a little lube burned off then settled down to a healthy 11.5ft/lbs But it gave me a welcome laugh as it was indeed a "Devil" of a job!

Excellent job How would I go about setting my Challenger trigger for a nice light let off. I understand that the rifle has to be cocked first; to be honest I were a bit worried about messing with a cocked rifle. What is your take on doing the trigger? Apparently the later Mercury's such as the Challenger have 2 stage triggers but I can't see how that works?
Hope you don't mind me asking. Atb. Derek

[junglie]

Take the stock bolts out & the stock off & you can cock the trigger mech by hand without loading. I can't remember which screw does what, but I think the front one is out for lighter in for heavier the other is sear engagement, i think. Anyhow with the stock off you can see clearly which one is sear engagement & not set it too fine then pop the stock on to test pull weight & feel. The two adjusting allen screws are not metric sizes btw & the smaller one is a hard size to find I remember. If you have trouble finding either I have them marked in my security bits set I'll look them out if you pm me derek.

[derekj]

Take the stock bolts out & the stock off & you can cock the trigger mech by hand without loading. I can't remember which screw does what, but I think the front one is out for lighter in for heavier the other is sear engagement, i think. Anyhow with the stock off you can see clearly which one is sear engagement & not set it too fine then pop the stock on to test pull weight & feel. The two adjusting allen screws are not metric sizes btw & the smaller one is a hard size to find I remember. If you have trouble finding either I have them marked in my security bits set I'll look them out if you pm me derek.

That's wonderful, I'll do as you say and cock the mechanism from there. Much safer. Thank you. Derek

[Airsporterman]

The edges of the sears on the Airsporters and Mercury's can be a little rough - resulting in drag and inconsistent 'let off' (a bit like a workmate I once had! )
A little work in these areas can be a bonus - but beware you don't overdo it or else the trigger can become very light resulting in the dreaded NDs!

ASM