Want to fit a silencer adapter to a Mk 5 Meteor or BSA Scorpion Pistol?

Just out of interest (it being Sunday and me being at a loose end) I measured the diameter of the barrels on my Mk5 Meteors and one of my BSA Scorpion pistols (the .177 one). As follows ...

Scorpion Pistol .... 15.5mm
Mk5 Meteor ......... 15.7mm

also my Mk2 Webley Vulcan in .177 ..... 14.75mm

The idea was to put a silencer on the .177 Meteor but in all honesty it would make it a bit long. Might finally get around to taking the piss-awful Webley Pro-System off the Vulcan and put a decent silencer on. It will involve cutting off the aluminium tube that's crushed onto the barrel from the internals of the silencer. I gas-rammed the Vulcan a couple of years ago and it's up there on the 12ft/lbs limit and does pop a bit without some moderation.

UPDATE - 9th June 2011



this is the tasty Webley Pro-System silencer ..


This is a later pic of the gun ..

Turns out that the tube that's crushed onto the end of the Vulcan barrel is actually steel not ally, and on closer inspection my guess it was heated up and shrunk on .. bit of a permanant fixture. Also it's noted that at some point between the gun leaving Brum and arriving at me (via North-West England which is where I bought it from) it lost about 4 inches off the barrel through some fairly injudicious use of a hacksaw and file. The gun shoots as straight as anything so whoever did it was either really lucky or they re-crowned the barrel. I've had a good look and it doesn't appear to have been crowned, but I'm not going to do anything about it on the basis that if it ain't broke, don't fix it.

I tried some Birchwood Casey Super Blue on the offending part and it's now matched to the rest of the barrel making the business end actually 15.95mm in diameter. Plan is to get one of those 16mm - 1/2UNF brass adapters off ebay and put a Weihrauch moderator on that's currently sat on the bulked AS2250X Crosman and getting bugger all use.

So it would seem I'm ending up putting a decent silencer on the Vulcan rather than on the old .177 Meteor. That's my life that is .. start off doing one thing and end up doing something else.

An email received and responded to ..

I got an email from a guy named George with some questions .. my responses are in bold/italic ...

"Hi George!

Hope you don't mind me emailing you, found your detailed blog about doing up a meteor or two and thought you might be able to advise me. – If I can help

I'm working on what I think is a mark 3.

I've put in standard spring, polished everything, relubed and put back together. – Good start!

Was putting out a measly 1.5 ft pound! I know what you mean .. frustrating.

Sorted out breech seal. – was the old one like crumbly cheese?

Now measly 3.4... Getting better though!

Will it make much difference replacing buffer washer and o ring do you think, they seem in reasonable nick? – It’s funny, you really can’t tell by looking at them. It’s possible the internal face of the cylinder is worn, and the O ring (this provides the gas seal in the cylinder) is not seating as snugly as it should. I had this problem on the .177 Mk5 I did up. I put some PTFE plumbers tape in the groove under the O ring on the piston head .. I cut the tape to half its width and wound it round twice as tight as I could get it without it snapping. Covered it with silicone oil, put the new O ring on, wiped off the excess and gently rebuilt the gun – be really careful not to damage the new O ring as the edges of the cylinder that you need to get it past can be razor sharp. It should be a sliding fit .. not so loose you can move it easily by hand, but not so tight you need to really force the piston ... hard to describe, but you’ll know when it’s right.

Could I have over polished piston so that it is letting air past? No, the piston doesn’t provide a gas seal, the O ring on the piston head does

I've spent a bit of time doing up the gun and want to get the power up to 9 any ideas what the problem could be? Gas seal .. O ring ..

I think I'll take it apart again and try pushing the piston covering the port to see if there is a leak. .. this will tell you that it’s losing air somewhere but it won’t tell you where .... Also maybe new buffer washer and oring and soak in silicon gun oil as you suggest which I didn't do before. ... this should do it

As an aside I've stripped all the parts back to bare metal (polished with gun stock wax which stops them rusting) which looks pretty cool - bluing was poor, used rust remover to remove it all. Sounds good, although it’d make it a bit visible to pigeons and squirrels!

As for the loose jaws, I think you mentioned using a drill bit? .. I did, don’t ask me what size. The best fix was to use a spring pin though.

What I did was tapped threads into the original pin at both ends and shortened it by a mil or two at each end so you can then use flat headed bolts into the pin on either side which pulls the jaws together as you tighten them, making it as tight as the ducks end you mentioned. .. sounds like a proper solution to me!

Any tips on upping power would be appreciated... .... it sounds to me like you’ve made a really good start. From what you say I reckon the issue is the gas seal provided by the O ring. There seems to be no hard & fast way to sort this beyond a little trial and error. I think I rebuilt the .22 Mk5 about seven times before I was happy with it, and the .177 was a bit more straightforward.



Thanks for getting in touch. I’m certainly not an expert, more of an enthusiastic amateur

Lee "