Posts Tagged ‘vintage airguns’
by Tom Gaylord, a.k.a. B.B. Pelletier
My rifle is actually a BSA Super Meteor.
Today, you’ll see how I fixed the bad muzzle crown on the BSA Super Meteor, and then we’ll see if that had any effect on the rifle’s accuracy. You might want to read Part 7, again, just to remind yourself of what I faced.
The BSA project has been just that — a project from the start. All I wanted to do was test another vintage spring-piston air rifle for you and report the results, but this particular air rifle has challenged me at every turn. From the time I bought it at the Roanoke airgun show last September, it’s been nothing but a prolonged learning scenario. I won’t bore you by recapping all that’s happened; but if you want to find out, read Parts 1 through 7.
At the end of Part 7, I showed you a nasty muzzle crown, which I surmised was the reason that all the pellets were leaving the barrel with a yaw to their axis. They weren’t tumbling, because every one of them struck the target paper in exactly the same orientation. They were yawing, or traveling forward while pointing off to one side. Because the barrel is rifled, they were spinning on their long axis, but that axis didn’t happen to coincide with their flight path.
The BSA Meteor crown has some serious nicks in it. The dark spot at 10 o’clock is the deepest. Compressed air could escape through this channel before any other part of the pellet leaves the bore, and the jet of air could push the pellet over on its side.
The solution was to crown the bore; but as you can see in the picture, the Meteor’s muzzle is counterbored by more than an inch. In other words, it isn’t where it appears to be from the side. It’s deep inside the barrel, where the theory says it shouldn’t get damaged as easily. Only this one was — perhaps from over-zealous cleaning through the muzzle. Who knows? The point is that it had to be fixed.
My shooting buddy Otho suggested a piloted counterbore to face off the crown true and square to the axis of the bore. And he volunteered to make the pilot, so I slugged the bore for him and found it was a diameter of 0.176 inches. That seemed odd to him because it’s larger than the bore of a .17-caliber rimfire bullet that’s about 0.172-inches. But that’s the difference between .17 caliber and .177 caliber — which is important for airgunners and firearms shooters to know. The pilot he made measures 0.1745 inches and fits the Meteor’s muzzle comfortably.
Otho made the pilot for this counterbore.
The counterbore chucked up perfectly in my portable electric drill. I allowed extra length for the bore to go down into the barrel and touch the muzzle without the drill chuck touching the barrel.
The counterbore is chucked in the drill and set to run true. It sticks out far enough to cut the crown without the drill chuck touching the barrel.
Plugging the barrel
Before starting the work, I pushed 3 fat pellets into the breech and then pushed them with a cleaning rod to within 2 inches of the true muzzle. These will keep the metal chips from dropping down the bore.
I oiled the counterbore and pilot with a good grade of light machine oil before inserting it into the muzzle of the gun. The drill was set on a slow speed, but I can also control the speed by how hard I squeeze the trigger. I wanted a slow steady turn without putting much pressure on the drill. The counterbore is sharp enough to cut the soft barrel metal without a lot of encouragement.
The drill is set to run slow, and I’m also slowing it more with the trigger. You don’t need speed for a cut like this.
After about 10 seconds of cutting, I removed the counterbore and cleaned the new crown with a cotton swab. There was a band of bright metal around the muzzle where the counterbore had cut. Upon close examination, I could still see gouges in the bright band. The gouges were deeper than the first cut.
The new crown is bright after the first cut, but there are still gouges that need to come out.
I cleaned the counterbore with a swab and oiled it again. Then, I made a second cut on the crown. This time, I felt the drill pulse as the cutter removed the uneven metal. It became smooth, and I knew the cut was finished. When I cleaned and inspected the new crown this time, it appeared smooth and even. The job was done.
I apologize for the blurriness of this picture. Focusing on the crown is very difficult when I’m also trying to light it from the same axis as the lens is pointing. The lens is about one inch from the end of the barrel, and this was the best picture I got. There are still some faint marks on the crown. After examination with a loupe, I didn’t think they would be a problem.
At this point, I felt the crown was as clean as I could get it. And there was a simple way to see if this had made a difference. I drove the pellets in the bore out the muzzle and a few steel chips came with them. Next, I shot two RWS Hobby pellets offhand from 12 feet. If the crown was good, they would cut the paper perfectly instead of hitting sideways. And that’s what happened.
So, I backed up to 8 yards and shot 2 more shots from an improvised rest. These 2 pellets landed very close to each other and also showed no signs of tipping. I felt the job was done.
The two lower shots were from 12 feet. They confirmed the pellets were hitting the paper straight-on. The two upper shots were from an improvised rest at about 8 yards. They told me the crown is probably working.
Now for the test!
The test is a rerun of the Part 7 accuracy test. I used every pellet from the last accuracy test and shot at the same 10 meters.
Ten Eley Wasps went into 2.256 inches at 10 meters.
If you compare these targets to those in Part 7, one thing jumps out at you. None of these pellets tipped when they went through the paper. So, crowning seems to have solved that problem!
But the accuracy seems no better. The Hobbys did group better in this test, but the Falcons grouped worse. With groups this large at 10 meters, I’m not willing to say anything has improved. I’ve had cheap Chinese air rifles group better than this.
I have one trick left up my sleeve. I’ve noticed that the Meteor rear sight seems hinky and difficult to adjust, and I suspect it jumps around as I shoot. It’s not loose to the touch, but I don’t trust it to hold zero.
I’ll do one more test of this rifle with either a dot sight or with the See All Open Sight if I can get it mounted to the Meteor. If that doesn’t work, I’ll probably abandon this air rifle as a bad investment.
by Tom Gaylord, a.k.a. B.B. Pelletier
My rifle is actually a BSA Super Meteor.
I’m headed to Las Vegas this weekend for the 2014 SHOT Show, so I’m asking veteran readers to help the newer readers more than usual. And I thank you in advance.
Tuesday’s blog will have something very important. It’s the first day of the SHOT Show, and I’ll show you something brand-new. It’s a pretty big deal, so it’s worth a look. Now, let’s get to today’s report.
Today, we’ll look at the accuracy of the BSA Super Meteor Mark IV that I’ve been working to restore. This report was never supposed to be an ongoing saga. It was supposed to be a quick 3-part look at a vintage air rifle, but the Meteor that I bought at the Roanoke airgun show last September turned out to need almost one of everything. So, I hunkered down and went to work.
I said in one of the earlier parts that fixing up an old spring-piston rifle is a lot like rebuilding an old tractor. Man, was that ever a prophesy! I had no idea that I would have to get down into the guts of the rifle to get it shooting again; but if you’ve followed along on all the earlier parts, you know that’s exactly what happened. Now that the old girl is shooting like she should, let’s see how accurate she is.
This is a vintage spring rifle with open sights, so I like to begin shooting those at 10 meters. Since I have no idea how accurate or inaccurate they are, it’s best to start close. If the groups show some promise, I can always back up to 25 yards and shoot a second test.
I figured a vintage airgun deserves a vintage pellet, so I broke out some obsolete Eley Wasps in .177 caliber as the first pellet. The first 2 shots were to sight in, and shot #1 was low, so I tried to adjust the rear sight up using the adjustment wheel. Alas — it didn’t move the sight! The backup plan was to loosen the rear sight blade and slide it higher. I also noted that the whole rear sight unit needed to be snugged down, so that was also done.
These .177 Eley Wasps are from the same timeframe as the Meteor rifle.
Loosen the 2 screws and slide the sight blade up to raise the point of impact.
Before we proceed, a word about .177 Eley Wasps is in order. Many of you know that the 5.56mm (.22-caliber) Eley Wasp is a particularly fat .22-caliber pellet. It’s often the best in vintage airguns whose bores are on the large side. But the .177-caliber Wasp is not an oversized pellet — at least not the ones I have. I often choose these pellets for guns with larger bores such as the Meteor, forgetting that these aren’t the best or biggest .177 pellets around.
I shot only 8 pellets at the target because the group grew to 3.559 inches between centers, and it didn’t seem worth my time to finish. But that wasn’t all I noticed. Most of the pellet holes are ripped out to the right, as if the pellets were not traveling straight. We know from the previous velocity test that this rifle now shoots fast enough to not tear target paper when the pellets pass through, so this tearing had to have been caused by the pellet’s orientation and not its velocity.
It only took 8 Eley Wasp pellets to convince me that this was not the right pellet for the Meteor. Notice the tearing of the paper! It’s all in the same direction. I’m cutting off parts of the bulls in this photo because they contain another group from another pellet.
Crosman Premier lite
These results were enough to convince me to use modern pellets in the Meteor. The next pellet I tested was the Crosman Premier lite. This time, I fired all 10 pellets, and the group was much smaller than before, but it still measured 1.73 inches between centers. That’s horrible for any air rifle at 10 meters!
What was even more surprising is the fact that the Premiers also tore paper to the right of the main pellet hole. In fact, they tore in exactly the same place!
It looks like 9 holes, but there are 10 Crosman Premier lite pellets in this group. It measures 1.73 inches between centers…and notice the tearing of the target paper in exactly the same way that the Eley Wasp pellets tore it.
If the pellets were tumbling in flight, the tears would be randomly scattered around the main hole because the tumbling pellet would change its orientation all the time. But because they are all in the same place, it looks like the pellets are tipping as they exit the muzzle and flying straight to the target in that tipped orientation. Hmmm! Have to think about that.
Air Arms Falcon
The next pellet I tried was the Falcon from Air Arms. I selected this pellet because the heads were sized large, at 4.52mm. They have the largest heads of any .177 pellets I have.
They put what looks like 9 shots into 1.863 inches between centers. Once again, several of the holes are torn on the right side.
The final pellet I tested was the RWS Hobby. This is a large wadcutter that sometimes is very accurate at 10 meters. But not this time. Ten went into a group that measures 2.05 inches between centers. They also tore the paper to the right of the main pellet holes.
I knew something was wrong with the rifle because these pellets all fly at different speeds. There’s no way a tumbling pellet can tear the paper in exactly the same place when they all get there at different times. For even one single type of pellet to do that is hard to believe, but for 4 different types…it’s impossible. The pellets have to be leaving the muzzle tipped on their edge and remain in that orientation all the way to the target.
I know that most of you have guessed what’s wrong with the rifle by this point, but I hadn’t. Of course, I didn’t have someone pushing my nose into the facts like you have in this report. It wasn’t until my buddy Otho came by for a visit. I showed him the targets (because he has an interest in the Meteor, as you recall), and he said, “I’ll bet that barrel needs to be recrowned.”
Oh, my gosh! How could I fail to see that? Of course that was the problem. When I brought out the Meteor for him to look at, he saw it right away. I bet you will, too. The muzzle is backbored by more than an inch; but with a tactical flashlight, we were able to look down inside.
See the dark spot at 10 o’clock? It appears to be a nick in the muzzle. How it got there I don’t know, but it should be fixed.
The saga continues!
Yep, this Meteor is like an old tractor, all right. Just when you think you have the thing running and looking spiffy — the magneto quits. These days, there’s only one old man in Kansas who can repair them. Actually, I protesteth too much because I really enjoy working on this gun. It wasn’t made in China, yet it has turned out to be even worse than most of the very poor-quality Chinese airguns I’ve tested in the past.
In truth, there’s a lot of great engineering in this rifle, as well as a ton of abuse. You BSA Meteor owners out there know that I’m not purposely beating up your favorite airgun. It’s just that it challenges me at every turn. But that’s a large part of what makes this hobby interesting. After all is said and done, I’m not upset.
OK, take that report on a Friday and run with it! Remember, I’m on my way to Las Vegas and cannot answer as many comments as normal.
by Tom Gaylord, a.k.a. B.B. Pelletier
It’s been a while since I wrote about this gun, I know. Airgunner Larry Hannusch told me how to disassemble it, and I started…only to stop when I encountered a barrier. I’ve resolved that barrier, and today I’ll show you the inside of my gun to the extent that I’ve disassembled it.
Larry told me to remove the screws on top and beneath the action that were obvious, then separate the two parts — action and stock. I removed 4 screws, and the action came loose from the stock a little bit. Then, it stopped cold. That was where I stopped working and set the gun aside. Yesterday, I picked it up and began from that point.
A bugelspanner (actually, correctly spelled buegelspanner or bügelspanner since the u has two dots — called an umlaut — over it) translates to a triggerguard-cocker. The triggerguard is pulled down to retract the piston and set the sear for firing.
Triggerguard is up in the shooting position.
The triggerguard lever is fastened to a pivoting axle bolt located in the back of the stock. The bolt shows in the photos above. Since this lever is connected to a linkage that’s connected to the back of a piston held under tension by powerful mainsprings, it made sense to me that it had to be disconnected from the piston for the stock to separate.
I removed the bolt that screws into a very long bushing inset into the opposite side of the butt. Then that bushing was tapped out the other side of the stock. But the cocking lever wasn’t quite free. At the top of the triggerguard lever, the cocking linkage passes through the lever and is prevented from coming free by a small screw that passes through one end of the linkage. I have arranged the two parts and their screw below for you to examine.
The triggerguard and cocking linkage, arranged as they are in the gun — I think! Until I assemble the gun, again, I won’t be sure of the correct orientation of the cocking link.
That tiny handmade screw goes through the hole in the cocking link and prevents it from slipping through the triggerguard when the gun is cocked. Notice that it has two smooth bearing surfaces — one on either side. As the gun is cocked, the cocking link moves up and down in the cocking slot that’s in back of the triggerguard. It’s a moving fulcrum.
This is the triggerguard lever pivot bushing and screw on which the lever pivots when during cocking. Note the smooth band around the base of the bushing. We may assume that’s where the pivoting happens.
The screw and pivot bushing have been removed from the stock.
The entire underside of the stock is open, allowing room for the cocking linkage to move.
When I removed the cocking link from the back of the piston rod, I found the screw that attached the link to the piston rod was sheared in two, plus the rest of the screw was very mangled from pressure and work. Clearly, this part is too soft and also overworked.
The screw that holds the cocking link to the rear of the piston rod is mangled and galled from too much strain. The threaded portion remains in the back of the piston rod and needs to be removed. This part may need to become a roller bearing.
The first part to come off the gun was actually the top action plate that also holds the rear sight. It is the anchor plate for 2 long screws and one short one that holds the action together. Once they were out, the plate didn’t come off without a lot of wiggling and some prying.
Three screws, and the top plate came off with the rear sight attached.
This is where the top plate came from.
The gun is now partially disassembled. The double-set trigger mechanism is exposed and can be disassembled and cleaned, but the piston is still under compression inside the compression chamber that hasn’t yet been separated from the barrel. To see the piston and mainsprings, The backplate that the piston rod passes through has to be drifed down out of its dovetail
The double set trigger assembly is now exposed for cleaning and possible disassembly. To remove it from the gun, it’s tapped down, freeing its front dovetail.
The double-set trigger assembly must now be removed downward from the cylinder dovetail, freeing the trigger plate and back plate from the cylinder and relieving tension on the mainsprings.
I found the number 80 on many of the larger, unique frame parts. I believe that’s either a serial number or an assembly number to keep all the parts together because this gun shows a lot of handmade parts and hand-fitting.
When I open the barrel, I see some dark particles that I believe are small chunks of leather that have broken off the piston seal, so it may be deteriorating. And I need to look at the condition of the mainsprings, plus probably lubricate them just a little.
The bottom plate on which the double-set trigger sits is dovetailed into the frame (the rear of the compression/spring tube). It has to be pushed straight down to relieve tension on the mainsprings, and I do this with by tapping with a rubber hammer. The plate comes out of the dovetail easily enough; but the double volute mainsprings are under considerable tension even at rest, and the trigger plate and separate backplate fly off the gun along with the volute springs.
The trigger plate has a dovetail at its front that grabs the rear of the cylinder and holds the powerplant together. The cylinder back plate (left in the photo) is held between the 2 parts. The black part that’s flopping down on the back plate is the sear.
The piston can now be withdrawn, and I can see that the leather seal has, indeed, deteriorated. The part that comes in contact with the air transfer port is damaged from repeated impacts. I think I’ve found the reason the gun fired so roughly.
Bugelspanner piston at the top is much fatter than the Beeman R1 gas-spring piston unit below, but the stroke is also shorter. The notch in the bugelspanner piston rod is the cocking notch.
The leather piston seal has deteriorated. It looks okay, but it’s crumbling and flaking off. This is why the gun fires so harshly.
Double volute springs attached to a central guide for the mainsprings of the bugelspanner. They’re in good condition but very dirty and dry.
The double-set trigger has a weak front trigger leaf spring, which accounts for it not setting well and firing too easily. That will also have to be corrected.
The inside of the compression chamber is filthy, but it doesn’t seem to be damaged. A good cleaning is all it needs.
For many of you, looking inside this airgun is probably like looking at the dark side of the moon. So many of the parts appear foreign to your eyes. All that has really changed over the years, though, is how the parts are designed. They work in the conventional way that modern spring-piston parts work, so they must be corrected in the same way that a modern spring-piston powerplant would need to be.
There are numerous major repair jobs that must be undertaken before this airgun will shoot again. There’s certainly lots of cleaning, which is followed by careful lubrication of many of the parts.
Some new parts have to be fabricated, as well. That will not be an easy task, but it’s worth the effort. I know you were hoping to see a test real soon, but that’s not going to happen. I have to feel my way around this gun carefully; because if every job isn’t done right, the gun won’t work when it goes back together. I’ll go about the work methodically and take some pictures as I go, but I probably won’t report on the gun again until all the work is completed.
by Tom Gaylord, a.k.a. B.B. Pelletier
My rifle is actually a BSA Super Meteor.
The last report on this BSA Super Meteor was on October 15. That’s how long it’s been since we saw this gun in print. But in the background, I’ve been doing lots of things that I’ll share with you today.
The last time we looked at this rifle, I was taking it apart and getting a lesson on how it was built and what was wrong with it. To summarize for you, this BSA Meteor is made from folded metal, in the same way Daisy BB guns are made. And the piston head was attached to the piston by means of an E-type circlip that was incapable of standing up to the stress. I can tell that by the damage that was done when that clip let go — but more because the Brits have invented a much better solution for fixing this gun today, when it does break down — and all of them are going to break!
I sent my order to T.R. Robb in the UK for a replacement piston head, o-rings and spacers. The problem is that when I sent in that order I didn’t pay attention to the fact that the same order button also got a piston head for a BSA Scorpion pistol, which is larger than the Meteor head. Well, guess which one Mr. Lysdexic ordered?
That’s right, I ordered the Scorpion piston head. And a couple days later, when I realized what I’d done and contacted T.R. Robb, they had already shipped the order. But to their credit, they sent a second piston head — this one was for a Scorpion, too. That’s right! They sent me 2 Scorpion piston heads and no Meteor head! But I’ll give them credit for trying to help me, for being very generous and refusing my offer to pay for the second head, and for being very prompt in shipping both heads. I had them in less than 10 days.
So, blog reader David Enoch — I now have a spare BSA Scorpion piston head that I believe you said you needed. The price will be right, too. You’ll pay what I paid, which was nothing.
Lots to see here. The replacement piston head is the shiny one on the left, the darker original is on the right. Obviously, the replacement part is larger and has to be cut down to fit. The blue spacer and 2 o-rings are just some of the soft parts that came in the kit. There were a total of 4 o-rings of different sizes and 2 more spacers of varying thicknesses. They allow you to set the power of your airgun, and they also allow for differences in the tolerances of different guns.
When I saw how large the piston head was, I knew it wouldn’t fit. I asked my friend Otho to cut it down for me on his lathe. He also had to cut the o-ring channel deeper at the same time.
Silly me — I thought that would solve everything. So, Otho took the head and had it back to me in a week. Then, I assembled it to the end of the piston and tried to insert the piston back into the spring tube. But it wouldn’t fit! I’d taken it out several weeks earlier, and now it wouldn’t fit back inside! It was like that pair of blue jeans that used to fit, before they suddenly and quite mysteriously shrank. I hate it when that happens — especially to jeans I’ve worn for years!
I took a more critical look at both the spring tube and the piston. Glory be — they’re both made of folded metal like a Red Ryder! Except that Red Ryder spring tubes are generally round, while both of these pieces had variable shapes, with a tendency toward the oval.
The tail end of the piston. Here you clearly see that it’s folded metal, tack-welded at each end.
At least that’s the theory! Here you see the weld at the piston head end has broken. Wonder why the piston is no longer round?
And, on the other side of the piston, opposite the broken weld, the solid metal has also cracked! Here you can see the nut that now holds the piston head to the piston body. It’s not about to break off like the circlip did!
Looking at just the condition of the piston gives you an idea of the shape this rifle is in. I don’t think the design of the rifle caused all this damage. I think people continued to try to cock and fire it after the piston head separated from the piston, and they hammered it into the mess you see here.
I examined the interior of the spring tube very critically at this point and found a lot of metal galling (shiny areas that indicate the scraping of metal against metal without lubrication). There was also a fair bit of surface rust. I also found that some of the folded metal edges of the spring tube that hold the trigger parts were bent into the interior of the spring tube and were blocking the passage of the piston. I fixed those with a Dremel tool, but the inside of the tube was too deep to reach.
I showed the spring tube and piston to Otho, who agreed with me as to the extent of the damage. He felt he might be able to clean out the tube with a tool that holds strips of abrasive paper and is spun in an electric drill. I don’t own that tool, so I was only too happy to let him have a go at it. He also said he could tack-weld and refinish the piston where it was separating.
So, Otho came to the rescue once more. And he was true to his word, because a week later I got back the tube and piston, ready for assembly. But that wasn’t the end of the rifle’s problems!
Otho welded the broken piston and dressed it round again.
Otho also welded the back side of the piston where it was cracked.
Loose barrel pivot
I had discovered that the barrel wobbled from side to side when I first got the rifle. And a little research online told me this is a common problem with Meteors from the 1970s. Apparently, when the forearm stock screws are tightened, the shape of the stock allows them to pull apart the action forks that hold the barrel breech. It’s a design flaw of the rifle, and the solution is to not over-tighten those screws. But how to fix it — since the barrel pivot is a pin, rather than a bolt? Well, this is something I know how to do.
I chucked the forks in the padded jaws of my bench vice and closed the jaws on the forks. When there was some inward tension on them, I hit the outside vice jaw with a 2-lb. ball-peen hammer, which sent a shock wave into the metal of the action forks and realigned their crystalline structure. Or at least that looks cool when I write it. I haven’t got a clue what really happens! All I know for sure is that when you do this, the metal takes a set in the new position, and now the action forks are about 5 thousandths of an inch smaller then the breechblock of the barrel that has to fit between them.
Finally, all the faults had been corrected, as far as I knew. The piston now slides into the spring tube with only a little friction, not unlike a Weihrauch piston in a Weihrauch gun. It was time to assemble the rifle!
Otho and I both think whoever designed this Super Meteor Mark IV was a genius at eliminating cost and making one thing do many jobs. The way this air rifle is designed should be a study in an engineering course, but the students would first have to know how others had done the same things with other spring-piston powerplants. At every turn, you can see the embodiment of the Spartan design.
And the parts that need to be hard are hard! I mean glass-hard! There’s no wear on any of the trigger parts, or on the piston, where it’s held by the sear. The boys at BSA knew what they were doing.
Since there had been so much metal galling in the spring tube, I first lubricated it with Moly Paste before any parts went back in. The molybdenum disulphide particles will bond with the metal surfaces and will not wash out over time. I applied this paste (which is a thick grease) with a swab made from a long thin dowel rod covered with a paper towel on one end.
This simple swab can be used to clean the inside of spring tubes/compression chambers, as well as to lubricate them.
After the inside of the spring/compression tube was lubricated, I also lubricated the outside of the piston head and piston tail with the same moly paste. I’d like to say a word about the piston head now. The kit of parts I was sent had 3 spacers of differing thicknesses. Any of them will work, but each gives you a piston head of a different length when it ‘s fastened to the piston body.
The way the Meteor is designed, adjusting the length of the piston head controls the power of the rifle. A shorter piston head will give a longer piston stroke and therefore greater power. I don’t want power. I want a smooth rifle that’s easy to cock and is also easy to shoot. So I went with a thicker spacer on the head.
Now, I lubricated both the piston head and the tail with moly. The center of the piston body can be left dry because it’s narrower than the ends and will never touch the inside of the spring tube.
The piston head is lubed with moly paste. No precision is required for this application because this stuff spreads as the gun is cocked and fired. The other end of the piston got the same treatment before it was slid back into the spring tube.
Once the piston was in the tube, I coated the mainspring with Beeman Spring Gel and slid it into place inside the piston. Don’t look for that product anywhere — it’s obsolete. It was a viscous silicone (Beeman only says it’s a synthetic in their catalog; but given where it’s going, I’m pretty sure it’s silicone) grease that dampened vibration without slowing the gun much, if any. So, pretty much any viscous silicone with the consistency of toothpaste should suffice. Or, you could do it the old-school way and just use a lithium-based grease.
The powerplant went together the same way it came apart; but the barrel, which was the next item, was harder to install because the action forks were now smaller, thanks to my repair. Nevertheless, the barrel did go into the action forks of the spring tube (I “buttoned” it in using the baseblock to spread the forks slightly), with the cocking link locked inside the piston and lots of moly grease on all metal surfaces that touch.
When it came time to close the barrel, I got a small surprise. It seems the spring-loaded chisel detent (the chisel-looking thingie that holds the barrel shut when the gun fires) was sticking out so far that the barrel wouldn’t close! Examination revealed that the detent is held in the baseblock by the pivot pin that passes through. How in the heck was I going to do that?
Well, if you think like a redneck cheapskate, which I am trained to do, you insert the pivot pin partway, lever the chisel detent back as far as it will go and then tap the pivot pin home. I could have closed my eyes for this maneuver, it went so smoothly. Obviously, I’d discovered something that the original 28-year-old BSA assembler, Trevor, could do 175 times in an 8-hour shift back in 1978.
From there, the only big task was to get the mainspring back inside the spring tube all the way. It only stuck out the end of the tube less than an inch, but it also had to go another full inch into the tube, where it would be held by a crosspin that’s profiled on one side to capture the base of the spring guide. It’s easier to just show you.
This is the side of the assembly pin that fits inside the base of the mainspring guide and holds it inside the rifle.
This 58-cent tool was made from a 4-inch plastic sprinkler pipe in about 20 minutes. With the action in the mainspring compressor, it pushes the washer at the base of the mainspring, while allowing the crosspin to be inserted through its slot. It isn’t beautiful, but it worked both times I used it and looks like it will hold up for dozens more jobs like this.
And the pin is back in place. The contours on the other side of the pin have meshed with the base of the spring guide.
I showed you these parts and the trigger parts in the earlier reports, namely in Parts 2 and 3. So I’m covering ground that I’ve already explained. When I took the rifle apart back in October, I didn’t have to use a mainspring compressor; but to get the mainspring back in place and insert the crosspin, I did. And it was easy.
And the remainder of the airgun went together exactly as it should. I have a theory. Whenever something goes together easily, it means I’ve left out something. I’m in my wetsuit but have forgotten to put on my briefs! I remember learning how to disassemble and assemble the M1 Garand rifle. I thought I could never learn, but a few weeks later I was stripping it like a pro. That’s the way BSA spring rifles are, I guess. You’d like them to come apart in 30 seconds without hand tools, but they don’t. However, once you’ve been down the path a few times, I’m sure the job seems simple.
This is the part I dreaded. Sure the parts were back together, but who was to say they were where they should be? Only cocking and firing the gun would tell me that. So I did. And it did! Hurrah!
The only task left to do is to clean the barrel. I had close to 2 months to do that while it was off the rifle; but to tell the truth, I wasn’t sure if I would be able to get the gun back to functioning again. No sense doing a great job on a barrel I’ll never use. But now the gun is working, so the next report can be about the velocity.
by Tom Gaylord, a.k.a. B.B. Pelletier
Today, I have a story for you. A couple weeks ago, one of our blog readers — a man named Eric — emailed me a link to a local craigslist.com posting. Eric met me at a gun show last year, and I sold him a Winchester model 427 (Diana 27) air rifle. He already knew about fine vintage airguns, and the 27 had been on his wish list for a while, but I don’t think he was a blog reader. Well, we fixed that right away! Since then, he’s been reading the blog and becoming more familiar with his new rifle and airguns in general
The listing he sent me showed a Tyrolean air rifle with the traditional high-cupped cheekpiece and hooked buttplate. What was even more fascinating were the double-set triggers and the large aperture sight located at the rear of the receiver, as well as the sporting sight mounted on the barrel.
The gun was a bügelspanner, or loosely translated, a triggerguard (lever) cocker. I’ve owned 2 bügelspanners in the past, but neither was as nice as this one. And the funny thing is that this was posted on craigslist! That’s funny because guns are sold on gun websites — not on a general website like craigslist.
But this posting had lasted for a minimum of 2 weeks before I saw it. So, I contacted the seller and, glory be, he still had it! We met last Sunday, did the transaction and this was one of those rare times when the gun was exactly as represented.
The gun is a smoothbore .25-caliber gun. The seller, named Joe, told me he had owned it for the past 34 years and had gotten it at the age of 8 as a gift from his father. The gun is much older — probably dating back to around the 1920s or ’30s.
It’s a spring-piston gun that has 2 opposed volute springs that compress against each other. They push a leather-covered piston in the same way that a coiled steel mainspring does in a conventional spring-piston gun, so this is just an odd form of spring-piston airgun.
Two volute springs push against each other when compressed.
The volute spring is a flat spring that’s been coiled and stretched into this shape.
I was attracted to this airgun because of a long, abiding interest in zummerstutzens — indoor gallery or parlor guns used for target shooting. I’ve been fascinated with them since I was a teenager and first read about them in Guns & Ammo back in the early 1960s.
The zimmerstutzen rifle is usually found in the Tyrolean style, but not always. It’s nominally 4mm, but there are more than 20 specific calibers for which the guns were bored. They fire either fixed ammunition (a cartridge) or separate ammo with a percussion cap and round lead ball loaded separately. Rather than get into the full description here, I invite you to read my full article about them. I normally don’t like giving homework assignments; but if you read that article and look at all the pictures, you’ll have a much better understanding of the gun we’re examining today.
The subject gun
I was inclined to believe the subject gun is a dart gun, but what little historical documentation there is mentions using pellets as well. I thought it was a dart gun because it’s set up for extreme accuracy, and I didn’t think that pellets could be that accurate in a smoothbore barrel. But we did do a test of the Diana 25 smoothbore at 10 meters and established that it is, in fact, very accurate at that distance. So, I really don’t know if I’m supposed to shoot darts or pellets in this gun. For the present, I only have pellets because .25-caliber darts are not that common. But I could certainly make some.
This type of gun either fits or doesn’t fit — there’s no in-between. I’m lucky that it fits me pretty well. But that sporting rear sight does get in the way of seeing the front sight. I would have to remove it to use the rear sight.
Why a sporting rear sight? Shooters in the US are not familiar with how European airgunners view target shooting. They use their guns for both precision target shooting and also for sporting use. I guess the best comparison would be to the Hunter Class of field target. Therefore, European target guns often have both a precision rear peep site and a second sporting rear sight located somewhere on the barrel. The subject gun has both.
The front sight is a fine post and bead, which is typical of all zimmerstutzens and, indeed, of many target guns from the 19th century. This sight is very fragile, so it’s protected by steel “ears” on both sides.
The sporting rear sight is adjusted in both directions by a clock key.
Rear peep sight is also adjust by a clock key and can be removed to use the sporting sight, only.
Front post-and-bead sight is delicate, so two steel ears protect it.
The gun has an octagonal barrel, which dates its manufacture to before World War II. It’s impossible to get a more precise date than that because these guns were made from the beginning of the 20th century until the early 1950s. The octagonal barrel also suggests a time before 1940. Most likely this gun was made in the 1920s or 30s, but I have no way of proving that.
The name Original is engraved on the barrel. Several sources say that this is a name used by Oskar Will in Zella Mehlis, Germany; but one source says that name, by itself, was used only by his competitors, and all of his guns also have the word Will on them, as in Original Will.
The name Original may mean this gun was made by Oskar Will of Zella Mehlis.
The gun is cocked by pressing down on the triggerguard, which is actually a long lever pivoted near the bottom rear of the butt. You can see the pivot pin sticking through the rear of the buttstock. A linkage pulls the piston back, compressing the two springs. To load the gun, you press a catch forward on the right side of the forearm, and the rear of the barrel can then be tipped up. You could call this a breakbarrel, but the barrel doesn’t have anything to do with cocking the springs. In that respect, the gun is like the breakbarrel Whiscombe rifles.
The cocking effort is pretty demanding. It’s on the order of 40 lbs., at least. I can’t see how a boy of 8 was able to cock this gun, but maybe his father cocked it for him until he grew into it.
Triggerguard is shown up…in the firing position.
Triggerguard is pulled down to cock the springs.
Push the catch forward, and the barrel can be tipped up for loading.
The double-set triggers on this gun are interesting. They work in the normal way — the rear trigger is pulled to set the front trigger and the front trigger fires the gun. However, there’s one difference. Many guns with double-set triggers will also fire when the front trigger is pulled without being set. This gun will not. If the trigger is not set, the gun cannot be fired.
Double-set triggers function normally, except the gun won’t fire unless the trigger is set. Many double-set triggers will fire when the front trigger hasn’t been set, but not this one.
Joe told me he shot the gun, so I figured it would be okay for me to do, too. First I dumped about 20 drops of 3-In-One oil down the air transfer port and gave it an hour to soak into the leather piston seal. The, I loaded an obsolete 20-grain Diana Magnum pellet and shot it into the trap from just a few feet away. The firing cycle was very harsh, so I won’t be doing that, again, until I can examine the condition of the powerplant. I could hear how slow the pellet moved, which leads me to suspect I’m right about this being a dart gun.
The gun is stocked with a light-colored walnut that’s checkered on the straight pistol grip. Also typical of the Tyrolean stock is the thumbrest that protrudes from the right side of the grip. That makes this a definite right-hand rifle!
This top view shows how thick the buttstock blank had to be to begin with!
The gun’s metal is finished with a combination of heavy nickel plate and hot-tank bluing. I would put the finish at 80-85 percent, which is to say…a lot! There are pepper tracks of rust scattered around the blued barrel, but an application of Ballistol and steel wool has begun to remove them. I’ll keep this up for as long as it takes to get down to smooth metal.
This report will not follow the traditional pattern of velocity testing followed by accuracy testing. For starters, I think the gun is too fragile to shoot that much, plus it does fire harshly. I need to find out what’s going on inside before I do much of anything.
I made this Part 1 so I could come back to it with a second report, though I have no plans for that right now. But as I learn more about it, there will be enough information to make an interesting Part 2.