New Old Pre War Rifle!!

[johnbaz 363]

Hi all

I recently bought this unknown pre war break barrel air rifle, It's very similar to the quarter stocked Diana mod27 but has definite differences such as the stock, Diana didn't use this kind of pistol gripped stock on them..

Also, The trigger guard on this has two screws to secure it at the front whereas the Diana has just one, Most of the rest of it is the same so maybe they made them for a retailer with the retailers name etched on the cylinder which has worn off over the decades!!

The slab sided trigger block on the Diana is slightly curved down, This one is bang straight!!, Also, The rear guard screw isn't a wood screw but rather a machine screw that screws in to the collar that the stock rod also goes in to!! Nothing like the Diana mod!!

The gun has been resprung and resealed by a (Useless) gunsmith five years ago and was said to be shooting fine! It was dieselling badly and when put through a chronoscope, It was very badly down on power, Measuring just 3.3ft lbs (My Webley Senior pistol shoots at 3.5ft lbs!! )..

I stipped the old girl to find a piston seal conversion was done (Was told it was synthetic) It had a piston head machined with a recess to take an O Ring, The recess was machined too wide for the 20x2.5mm O Ring that was fitted and when I covered the transfer port and pushed the piston down the bore, There was no resistence whatsoever ..

After work on friday I nipped in to a seals and Bearings company and bought six 20x3mm O Rings for the change in my pocket!! (They thrust the charity box under your nose every time!! ) and fitted one when I got home! I had already tried a 20x3.5 and couldn't get the piston back in to the cylinder so I reckoned the 3mm thick one would be perfect!! I wasn't diasppointed! When I blocked the transfer port and pushed the piston down the bore again, It wouldn't go to the end until I removed my finger from the tp

The breech seal was also leaking, Each shot sent a plume of blue smoke straight upp'ards! I cut three washer/spacers from some card, Put them in the recess of the barrel and replaced the seal, It still leaks slightly but nowhere near as much as it did!!, Still room for improvement by putting a stronger spring in the barrel detent or making a thicker seal..

The 'Gunsmith' (And I use the term loosely!) seems to have had a glut of grease and it seemed like he'd grease the gubbins with a number four coal shovel!

 

The gun is shooting more consistently now with more power though I had to reinstate the Ox spring as out of the thirty or so mainsprings I have, Not a single one would fit correctly!

 

 

Some pics

 

 

 

 

The stock was cracked on both sides, The gunsmith was supposed to have 'stabilised' it, They opened up dead easily prying with a screwdriver so I filled the cracks with PVA glue and worked it open and closed until capilliary action drew the glue all the way through to the other side, I clamped it for the next twenty four hours to set..

 

 

 

 

It was too dark to Chrono the gun by the time i'd done but I shot a pellet at a concrete slab from a couple of feet away before the work then again after, The pellet is deformed much more after, I think it's still only shooting at around six or seven ft lbs though, I've not had chance to chrono it since, Can't tomorrow either so i'll try to do it on tuesday!!

I've enjoyed playing with this gun and hope to squeeze a bit more power and smoothness by returning it to a leather parachute seal and round section spring in the future

 

 

 

Cheers, John

Edited December 12, 2016 by johnbaz

[Rez 4,961]

No this is a seriously epic post.

 

I shall now read your text

[3175darren 1,102]

Great right up, good luck with breathing a little life back into the old girl,

[mark williams 7,566]

Great post JB

 

 

[philpot 5,069]

Lovely old gun John and an interesting thread.

 

Sheffield only has three RFD's that supposedly have gunsmiths and I doubt it was John at Hardy's so I can have a small wager that I know which one it was.

 

Phil

[johnbaz 363]

Lovely old gun John and an interesting thread.

 

Sheffield only has three RFD's that supposedly have gunsmiths and I doubt it was John at Hardy's so I can have a small wager that I know which one it was.

 

Phil

The work wasn't carried out by a gunsmith in Sheffield Phil, It was a gunsmith in Hampshire I think!!

 

The gun was taken to a gunsmith five years ago for the work carrying out, It was his fathers gun but his grandfather bought it new!!

 

 

Cheers, John

Edited December 12, 2016 by johnbaz

[philpot 5,069]

Ah, I see, well there is one in Sheff I would not trust a catapult with but I had better keep that one quiet.

 

All the best with it John.

 

Phil

[johnbaz 363]

Hi all

Well! I got the chrono out today and found that the muzzle energy had only risen to 5.28ft lbs so around the same output as my BSA Scorpion break barrel pistol!!

I was going to make a 25mm leather parachute seal for the piston head but I found five for sale on fleabay for around £11 so I bought them, I hope making it back to a leather seal will up the power a bit but also I'm hoping the gun will buffer better to stop the piston slamming in to the end of the cylinder!

When they arrive, I'll get straight on with swapping them over and report any change in performance be it up or down!!



Cheers, John