Stripping my s/h 0.22 Remington Express Compact

[TonyL]

I'm sure you're right with this approach. It's nice to keep the spend low, especially on a budget priced gun. Going by your description of internal finish and lubrication, I'm sure an "old-fashioned" polish and tune will yield a positive transformation. And, as evert says, once hand finished and lovingly reassembled, you'll be sure in the knowledge that all's well inside.. If you can find a way of making up a top hat, I'm sure that will be most beneficial, too.

[Mr.Fixit-Norm]

I'm sure you're right with this approach. It's nice to keep the spend low, especially on a budget priced gun. Going by your description of internal finish and lubrication, I'm sure an "old-fashioned" polish and tune will yield a positive transformation. And, as evert says, once hand finished and lovingly reassembled, you'll be sure in the knowledge that all's well inside.. If you can find a way of making up a top hat, I'm sure that will be most beneficial, too.

In its standard form the end of the spring in the piston is centralised by a raised section which fits inside the end of the spring and the spring ‘turns’ on the outside flange. I say ‘turns’, even having polished the end up a bit it’s still quite graunchy to turn. One of the PTFE (?) preload washes from my HW tinbum kit is a perfect match to the outside diameter of the spring, fits in the piston sleeve and even has the right ID to fit over the spring locator in the piston ( how lucky/weird is that )

My plan would be to make a top hat with the bare minimum thickness and length, to go up against the tinbum washer, however even then I reckon it’ll add about 5mm of preload in total ! This may make it harder to cock so ultimately I might then have to remove 1/2 a coil maybe ??

I did have a look at the breech seal this afternoon and I think I might have mistakenly said it was 8.5 OD by 2.5, it should of course be 8.5 ID
Typically having gone through a large O ring kit and my odds and ends ones I don’t have one that will fit. I know I can order them from ‘that’ place but for the time being I’ve filed down the OD of a 0.2mm washer I found and put that behind the existing seal to make it slightly more proud of the breech.

I have a new piston seal on the way as well.

I decided as I couldn’t do too much today that I’d take a load of measurements of the internals and list them, as they may be of use to someone else. Please bear in mind these are for my gun and have been measured with a digital calliper ( zero checked after each measurement )
I’ve put ‘plastic’ for the inner spring guide and piston seal as I’m not sure what they’re made of and didn’t want to look a tit quoting something they’re not

Oh if anyone knows how to date these guns, mines got 140XEX 053184 on the Cylinder

Norm

Cylinder.

ID - 28mm
Wall thickness 2.0mm
Port 4mm at front tapered to 3.5mm inside ( measured with drills as I had no other way )
Port depth 20mm
Sloping breech with sprung ball lockup.

Piston.

Seal is ‘plastic’ parachute style 28.2mm max diameter x 4.75mm depth - bear in mind this is the old one !
Piston head diameter- 27.5mm
Piston is turned steel with machined slot, not folded steel like some cheap ones.
Weight inc seal - 269g
Total length to skirt ( inc seal ) - 131mm
Head to main body 11.9mm
Cocking rod from skirt to end - 32mm x 10mm diameter
Internal spring shoulder is 3mm with further stepped 3mm reduction which fits inside end of spring.


Outer spring guide/piston sleeve

Material - steel
Length - 106mm ( when in piston it fits level with skirt )
OD - 23.0 - 23.13mm
ID - 21.6 - 21.9mm
Hole diameter at piston flange end - 15.65mm

Inner spring Guide.

Material ‘plastic’
Length - 111mm inc stepped out head which fits into recess in trigger block.
OD - 13.9 - 14.0mm
ID - 10.5mm ( average )
Metal washer between end of spring and spring guide, 26.75mm OD, 16mm ID, 1.03mm thick and appears to be blued ?

Spring.

Round section wire gauge 3.0 - 3.13mm
OD - 20.5mm
ID - 14.3mm
Length - 234mm
Coils - 28

[Mr.Fixit-Norm]

Just to add that contrary to my earlier cursory examination, the inner and outer spring guides are actually quite a decent fit and not too sloppy. Which is probably why it didn’t twang too much despite being completely devoid of lubrication

Norm

[Mr.Fixit-Norm]

Pics to go with the info above . All the below are taken as they came out of the gun !

Norm

[TonyL]

Excellent detail and pictures, Norm.

Re that extra preload afforded by the top hat, I was going to suggest maybe just collapsing a coil. But, looking at the spring ends (a little "kinked over" or just the picture angle?), I think I might be tempted to take a little off each end / re-grind square? A little bit of polishing and correct lubrication should reduce friction slightly, possibly raising power and speeding the firing cycle up slightly as well as smoothing things out? If a little too much had to come off the spring to "square it up", as you know, some preload washers will sort.

[Mr.Fixit-Norm]

Excellent detail and pictures, Norm.

Re that extra preload afforded by the top hat, I was going to suggest maybe just collapsing a coil. But, looking at the spring ends (a little "kinked over" or just the picture angle?), I think I might be tempted to take a little off each end / re-grind square? A little bit of polishing and correct lubrication should reduce friction slightly, possibly raising power and speeding the firing cycle up slightly as well as smoothing things out? If a little too much had to come off the spring to "square it up", as you know, some preload washers will sort.

Thanks Tony, re the spring ends I think it’s the picture angle. I used my phone to take the picture looked at it and thought it looks odd but the actual spring is straight and the ends are quite good. When I polished them slightly there are some little bits that remained unpolished ( I only did it by hand on some 400 wet and dry with oil on ), so I could carefully grind them a bit flatter, that would lose maybe 1-1.5mm of preload as well which would be a plus.

[Mr.Fixit-Norm]

The replacement piston seal has turned up today so I’ll start the reassemble tomorrow. I’ve had two go’s at making a top hat for the spring but failed miserably each time

The problem is that it’s such a thin delicate piece to make that I’m finding it’s beyond my machining capabilities

I made the first top hat ok but then it went pear shaped when I tried to drill the 11mm hole down the middle, then I tried to do the hole first then machine the head and shaft, that failed as it was too thin and wouldn’t hold in the lathe properly.

I’ve decided that if I can ensure the spring ends are perfectly squared off and polished and I use the ptfe(?) preload washer inside the piston sleeve then the spring when suitably lubricated should run smoothly enough. ( it certainly can’t be any worse than it was ! )

Norm