Heanel Mod 1 DRP, Fixing and reassembly

Heanel Mod I DRP

Even though this air rifle was 75 years old there were still a lot of sharp edges on it, so I needed to get the draper mini drill out and deburr the compression tube. 

I thought it wise to clean the inside first as I didn't want to clean it with bits of deburred metal everywhere. It would also be nice to see if any damage had been caused by the nail that was embedded in the leather piston seal.

Hole left by the rivet in the piston face.

I used medium guage wire wool clamped onto and wrapped around the cleaning rod, it was dipped in white spirits and the inside of the compression tube was given a good all round scrub, and this was followed with a fine grade wire wool and then kitchen towel. 

Coarsest grade of wire wool removed most of the crud.

The inside of the compression tube was mirror smooth and shiny along the whole length, however some of the leather piston seal had stuck to the end of the tube, so I carefully chipped this off with the end of the cleaning rod. Now I could see that there were slight markings below the transfer port caused by the head of the nail, though these were nothing of concern. I did notice that the transfer port ran from the centre up to the barrel and by using the cleaning rod as a guide could see it was about 3 cm long.

White spirits stops most of the crud from collecting on the outside of the wire wool.

Using a craft blade I scraped the hard surface off the leather piston seal and shaved off any lumps and bumps off the face, 

A sharp blade brings life back to what appeared to be one knackered piston seal.

but not from around the hole left by the nail. Pouring some 3 in 1 oil into a milk bottle lid, I put the leather seal in to soak for a few hours.

Soaking in 3 in 1. A red plastic back plate give a flat surface for the leather seal to sit on.

When it came out, I placed it on a kitchen towel to soak up the excess, then pressed hard against a table surface. 

Remove as much excess oil as possible, it's going to smoke for a while as it is.

The seal appeared to have a new lease of life and a compression test proved there was new life in it now. Leather seals need a quick push to start to seal the compression tube unlike O ring and parachute seals which will seal straight off.

One restored leather piston seal.

I deburred the cocking slide and the pivot pin holes from the inside of the tube, 

Still has sharp edges after 75 years.

then screwed the grub screw for the barrel lock bar right in and deburred any metal created by the cocking linkage. 

That grub screw should come right out now.

White spirits and kitchen towel were used to remove any metal grindings from the inside of the compression tube, then I used 3 in 1 oil on some 0000 wire wool and cleaned every external surface of the rifle while it was dismantled.

0000 wire wool and oil removes rust but leaves whatever bluing is left on the action.

Now the leather piston seal was soft with no excess oil when pressed. It was screwed back on to the piston body, then the piston unit was replaced in the compression tube. 

A polish and light greasing.

The trigger housing has enough spring tension to hold the main spring in place with its preload.

With some Abby LT 2 grease liberally spread over the original main spring and spring guide, they followed on behind. I could always order a new spring later and this one was still a lot stiffer than the length of spring I ordered a while back.

The original main spring.

The trigger housing inner sleeve was still well and truly spring loaded and with it lined up, I carefully squeezed the forward end into the rear of the compression tube. I then gently tapped the rear of the rifle against the floor until the inner sleeve was back in place. 

This shows how much spring tension there is in the trigger housing.

The spring tension of the sleeve was enough to hold the main spring under preload and with the aid of a screwdriver the holes were lined up, 

All lined up.

the trigger was lined up and the pivot bolt fitted. With the safety in the off position and the trigger pushed forward, I replaced the end cap. With the end cap lined up, the retaining pin was fitted, it required the aid of a hammer to drive it home fully.

That pin takes some effort to fit as well as remove, so bear that in mind if you have to do this.

This was finger tight as there is a cut out in the stock for it to fit in.

The grub screw that holds the barrel locking detent bar unscrewed easily now that the end of the hole had been deburred.

A fair bit of wear and tear on this grub screw over the years, but it was easily fixed.

The bar and spring were removed, cleaned, greased with a little LT 2 and put back, with the head of the grub screw in a little deeper so that the cocking linkage wouldn't damage it again. 

Detent bar and spring all cleaned up.

 With a little grease on all the moving parts, the cocking linkage was slipped through the bridge and slotted into the compression tube, 

Guide for the articulated cocking linkage and threads for the fore stock screws.

the unlocking latch and breech were placed back in the forks and the pivot screw was replaced followed by the locking screw.

The pivot bolt goes in so much easier with the barrel broken.

It was a lot easier to tighten the breech pivot screw with the barrel unlocked as if it was ready to load, and this was without a breech seal in place.

The old leather breech seal was well beyond repair so I resorted to my trusty box of rubber O rings, 

Leather breach seal well beyond repair.

I did not have a three mm O ring of the right diameter so I cut one to the right size and super glued the ends together. 

New breech seal made from a section of rubber O ring.

It was made a tiny fraction larger so it would sit in the breech under its own pressure, the breech was closed to push the seal all the way home and a perfect seal appears to be produced.

New rubber breech seal fitted into place.

With the rifle lubed and put back together, I fitted it back into the stock, using a screw driver to hold the trigger tension spring back until the trigger was in place for the spring to fit over the tab.

Easing the tension spring back to fit on the back of the trigger.

Then it was a simple matter of fitting the stock screws. Each screw was fitted loosely at first allowing the action a little adjustability in the stock. This way all the screws attached correctly and then were tightened up fully. There is nothing more annoying than tightening one fore stock screw all the way home, only to find the other side won't fit.

Rifle back together, i gave the stock a rub down with wire wool to discover some lovely wood.

All I need to do now is build or bodge some sort of rear sight, the original sight is a simple affair so should be easy enough to make a rough copy. The safety still doesn't work, but I have an idea on how to remedy that, and the barrel lock could do with a new spring behind the detent bar. Anyway, the rifle fires with some authority now for it's size, but I will have to wait until I get a new chrony to find out what power it is producing.

TTFN

Wing Commander Sir Nigel Tetlington-Smythe.


   

.22 BSA Meteor Mk IV Reassembly

In a far flung corner of the kitchen, south of the bread bin and east of the kettle, just past the pile of battery chargers and assorted bike lights, sat the dismantled BSA Meteor. It sat there for a week and every time i made a cup of tea or dinner, i thought, i really should put this back together and get some pictures. So one day while i had a korma simmering away, it , the tool kit, and all my other bits and bobs got moved to the kitchen table and work commensed.

 The serial number puts this as a late model MkIV.

Even though this air rifle is about four decades old, general wear a tear had not removed all the burrs and sharp edges, so attaching a small grinding head to the Draper mini drill i gave the rifle a once over. 

Removing burrs from where the cocking arm is fitted.

Removing the sharp edge to the piston and compression tube cocking slot by gently running the grinding head along, 

Old air rifles still have a sharp edge on the piston as a rule.

and the edges and corners where the cocking arm goes in as well as the inner edges of the holes for the main spring retaining pin. 

Main spring retaining pin holes tend to need deburring to protect the piston seal.

Then using the cleaning rod with some white spirit on some kitchen towel i cleaned the inside of the piston and compression tube, i didn't want any tiny bits of metal dust from the grinding buggering up the O ring seal.

Clean the metal dust out of the tube and piston before reassembly.

The piston with the old O ring would slide half way down the compression tube with my finger over the transfer port telling me the O ring seal was very worn, 

With the old piston seal this is where the piston rested with the transfer port blocked.

so the O ring seal came off and a new one was sized up from the big red box of O rings. 

A slightly undersized O ring makes a good fit as a general rule.

 The inner diameter of the compression tube is 26 mm but a 3 mm thick O ring that size  was a tad to big on the piston, so going the next size down had the O ring fitting the piston head pretty snug. It was also a snug fit in the compression tube and stayed were it was when i tried to push it down with my finger over the transfer port, and took very little pressure to move the piston when i removed my finger from the transfer port, perfect!

With new O ring the piston stays at the top with the transfer port blocked

Applying a little Abbey SM2 to the O ring seal and some Abbey LT50 below the piston head and on the skirt,

A touch of Abbey SM 2 for the O ring seal.

A dab of Abbey LT50 (moly grease) for the head and skirt of the piston body.

 the piston was fitted into the compression tube with both cocking slots aligned. I cleaned the mainspring and polished the ends with the mini drill as it saves time and blisters,

Just a few of the many useful attachments for the mini drill.

 and applying a liberal amount of LT 50 grease and a a bronze slip washer to the end i fitted it in the piston. 

Bronze slip washer, main spring, and not too much moly grease.

The washer that sits at the end of the spring guide and holds the main spring is a little chewed up, so another bronze slip washer was placed between it and the main spring. With a little LT 50 grease over all surfaces it was put in the end of the main spring, i left out the 4 mm delrin spacer i had in it from last time. I made sure the washer was a tight as possible to the spring guide, as it slips down the guide and rests against a slight lip.

Spring guide, spring support washer, and bronze slip washer before a light coating of moly grease.

Placing the compression tube assembly in the spring compressor with the fitting tool in place the two inches of pre load was pushed back in, it needed a light guiding hand to get it past the end of the tube. 

Min spring removal tool will need guiding by hand as it enters the compression tube.

The spring guide stayed where it was and had to be teased up with a screw driver so the retaining pin would fit, it also aligned the retaining pin holes with the cut out in the special tool. 

Screw driver will clear the path of the retaining pin.

The retaining pin slipped in the right way around and pressure was released from the spring compressor, there is a little chip out of the shaped side if the retaining pin but it's not on a pressure bearing side.

 The pressure bearing side of the pin is on the undamaged side as the spring compressor is released.

The barrel had a crap home made delrin breech seal which was removed and cleaned, and a spare breech seal i had sitting in the spares box put in it's place.

New BSA breech seal is fitted.

 Over the years the pivot pin in the breech had worn the breech hole a tad wider making the the barrel loose and move in the forks, and the only way to fix this without replacing the barrel is to shim the hole.

A very worn pivot pin hole on the breech.

 I originally used a piece of bar the same diameter as the pin to hold a shim cut from a tango can in place in the breech when fitting the pivot pin, i had lost that so i used a piece of 6 mm wooden dowel which had swollen slightly to the .25 inch which is the diameter of the pin..The dowel was cut so it was the same width as the breech and a strip of shim also cut to that size, the shim was wrapped around the dowel and where it creased where it met the start of the shim it was cut. 

Shim material is rolled around the dowel and cut to size.

Applying a little spot of LT 50 to the breech hole the dowel with the shim around it was pushed in sightly. The detent bar and spring were greased a replaced, 

Moly grease the detent bar and spring

and pushing it down on the back of a chair the dowel and shim where pushed all the way in so they were flush with the breech holding the detent bar in place.

Dowel and shim holding the detent bar in place.

The forks had been bent out because the stock screws had bit into the stock and push the tabs below outwards by pressing against the breech, i had bent them back in the vice making sure i had something between them so as not to damage them. 

Pressure from a vice staightens out the forks.

With this done the barrel breech was very tight between the forks, slipping the breech behind the pivot hole upside down and flipping around so the holes lined up. Making sure the lightly greased pivot pin was entering the right way around through the left hand fork it was gently tapped through the breech with a rubber mallet, the pin pushed the dowel out the other side leaving the shim behind. 

The barrel is uncocked at this point so the pivot pin can drive all the way home.

When the pin reached the other fork the barrel was cocked making it easier to guide it all the way home, as i didn't want to knock the forks out of alignment again.With the barrel fitted the cocking arm was ground for sharp edges, cleaned, greased both ends, then fitted into the compression chamber, then the breech.

Fitting the cocking arm with a dab of moly grease at each end.

Getting on to the trigger i had noticed that a small bit had broken off that held the spring,it held but needed cutting deeper to make it more secure.

The trigger with a bit broken off it seems to be made of cast metal.

So a deeper groove was cut using the cutting disk off the mini drill, this also has a benefit by creating less tension on the trigger.

Cutting a lip to hold the trigger spring securely.

Now the sear could be replaced, followed by the trigger, then the stop pin behind that.

The fitting of the pins in the trigger assembly is reletively easy.

Now the action and barrel were sorted the plastic end cap can go on the back, the stock was attached by the trigger guard screw a little, then the guard was slipped in and the screw tightened by finger then finished with a screw driver.

I sometimes have to waggle the trigger guard slightly to slip it into place.

Finally the front stock screws had to have enough washers to make sure the forks weren't pushed out when tightened, ideally some sort of brass cup would do the job here.

The forstock screws are pretty knackered, but hold tight with some washers to stop them pushing the forks apart.

Seeing as the rear sights were missing i decided to fit the Rangeright 4x32 scope for testing, i dont know what it is about me and old BSA's but they are always missing the rear sights when i get my hands on them.

Ready for a trip to the woods.

That's the Meteor sorted for now, all i need to do is sight it in and see how it does. If all goes well with that then i might clean and oil the stock and put some enamel paint on the metal work, mind you i quite like the bare metal finish when it's cleaned, polished and oiled.

TTFN

Wing Commander Sir Nigel Tetlington-Smythe