by Tom Gaylord
Writing as B.B. Pelletier

BSA Meteor
BSA Meteor Mark I.

Part 1
Part 2
Part 3
Part 4

A history of airguns

This report covers:

  • Disassembly
  • Mainspring compressor
  • The trigger!!!
  • Rust!
  • Other parts
  • Trigger parts
  • Mainspring
  • Lubrication and assembly
  • Trigger
  • Cocking effort and trigger pull
  • RWS Hobbys
  • RWS Superpoint
  • JSB Exact RS
  • Discussion

Today I am disassembling the BSA Meteor Mark I for cleaning, inside and out. I’m going to get rid of that pesky rust, plus all the grit I saw when the gun was apart last time. I’ll also be able to tell you how well Tune in a Tube had spread throughout the action,. which is something most owners will never know. There is a lot more to today’s report, so let’s get started.

Disassembly

This time I knew exactly how the Meteor would come apart. Even the trigger that I told you is different from the trigger in my Meteor Mark IV was easy to disassemble, although I will come back to it at the end of the report.

Mainspring compressor

I used the new mainspring compressor from Sun Optics to disassemble the rifle. It only comes into play for about 8 minutes, but it is essential to have. This time I knew the compressor better and was able to install the rifle quickly. I needed it for 5 minutes for disassembly and about 3 minutes when the gun went together again. It worked perfectly and I have to give it a good rating as an essential piece of equipment for spring gun disassembly.

The trigger!!!

The trigger in the Mark I (and I believe the Mark II, as well) Meteor is different that the later triggers and a bit more complex. This trigger is held in by three pins, one of which doesn’t hold anything, but does serve as a spring anchor point.

The trigger blade is held by the lowest pin that passes through the walls of the trigger assembly box. That pin is easily pressed out with finger pressure. When it comes out, the trigger blade and the separate trigger return spring come out of the trigger box.

BSA Meteor trigger
BSA Meteor Mark I trigger blade out. The pin above and to the right of this one holds no parts in the assembly. It anchors two wire springs and keeps the sear positioned at the top of the trigger.

Once the trigger blade is out, press out the pin above it and the sear will flop down. Press out the larger sear pin at the front of the trigger box and the sear comes out of the rifle with its spring. All pins came out with little coaxing.

BSA Meteor trigger sear loose
When the second pin is out the sear drops down, away from the piston path. Its wire spring tip, seen here, was resting on top of the second pin when it was in the trigger box. It kept upward pressure on the sear, to pop it up into the piston’s path when the gun was cocked.

Once the sear is removed set all the pins and parts aside for cleaning. The mainspring and piston can now come out of the spring tube. Since I covered that in detail in Part 2 of the Mark IV report, I’m not addressing it today.

The internal parts were all well-coated by the Tune in a Tube grease, except for the outside of the piston body. That was relatively dry. I think the ridges on both ends of the piston scrape the inside of the tube wall dry and don’t allow the grease to get on the side of the piston. But since that part never touches anything, it can be as dry as a bone.

Rust!

The piston body was covered with some deep rust patches, though. I showed you a picture of that in Part 3. I had to get rid of the rust because it was preying on me, so I started with steel wool but wound up using a sharp knife to scrape it off. I thought it would leave a deeply pitted surface, but it proved to be surprisingly smooth after all the rust was gone. For the future I wiped the piston body with Ballistol. I then cleaned the inside of the piston body with a paper towel and cotton swabs.

BSA Meteor piston body
A quick scrape with a sharp knife, followed by a rub with 0000 steel wool and Ballistol and the piston is rust free.The clean piston is on the bottom.

Other parts

The inside of the spring tube was relatively clean, but I wrapped some paper towel around the end of a dowel and wiped it dry. I then turned to the barrel and cleaned the breech pivot area and the detent and spring. I oiled the detent spring with Ballistol and lubed the outside of the detent body with moly grease.

BSA Meteor detent
That cutout in the detent allows the barrel pivot pin to pass.

The sides of the breech were lubed with moly grease. They have some places where there is galling and this will hopefully end it.

Trigger parts

The trigger parts were all covered with grit, but no rust. I brushed them with a steel wire brush, followed by steel wool and then a light coat of Ballistol. The sear and trigger contact points got a smear of moly as the trigger was assembled.

Mainspring

I threaded a paper towel through the mainspring coils and threaded it along the entire length of the spring. This removed the excess grease from Tune in a Tube, but left a thin film.

Lubrication and assembly

A spring gun gets lubricated as it is assembled. Depending on the design of the gun, lube is added just before the parts go into the gun. That keeps them clean and also prevents spreading grease around the workspace.

The piston went in first. The front and rear rings were lubed with moly grease and then inserted into the spring tube. The barrel must go on after the piston is installed because the cocking link interfaces with the piston. The tip of the link that connects to the piston got a dab of moly grease and the pivot pin was lubed with moly before it was slid through the hole. The detent must be pressed in for the pivot pin to clear it. Then the pin slides all the way through the breech fork and the barrel is on!

Now the mainspring can be slid into the piston. I lubed it lightly with some black tar grease I have had for years and was careful to slide it into the gun as it was greased. That kept the outside of the gun as clean as possible. With the spring guide back in the spring (black tar on the outside of the guide), the action is ready to go back together. That went quick.

Trigger

I assembled the trigger in the reverse order from disassembly. First the sear and sear pin go in, then the anchor pin slides in place and finally the trigger blade with its return spring and pin go into the trigger box. But, when the rifle was back in the stock, the trigger was difficult to pull and the blade didn’t reset after firing. I had not gotten the trigger return spring back in the right position. When I removed the stock again to look, I saw that the end of the trigger return spring was not anchored by that middle pin I showed you.

The end of the sear return spring goes above the anchor pin, and the trigger return spring hook goes below the anchor pin. Each spring keeps their respective part tensioned correctly.

BSA Meteor trigger return spring
That short leg on the trigger return spring sticking out of the blade has to be hooked beneath the anchor pin to work.

There is nothing online that shows this, but if you don’t do it this way the Meteor’s trigger cannot function. This is what I was referring to when I said this trigger is complex. It isn’t difficult, but all the parts have to be in the right place for the trigger to work. You don’t have to force anything into place; it all fits as designed.

That done, the rifle went back in the stock and now functioned perfectly. Except for one small thing. The rifle now buzzed just a little with each shot. It was much better than before we began, but not as good as it was following the first application of Tune in a Tube.

I wasn’t going to allow that after all the work I’d done, so the rifle came back out of the stock and I applied some Tune in a Tube without further disassembly, just as I had before. Then back into the stock and this time the action was dead calm with each shot. That’s real irony for you!

Of course I could have stripped the rifle a second time and put more black tar on the parts. That would have made it dead calm upon firing, but from past experience I knew it would also slow the rifle down by 20-30 f.p.s. or more. In the past I would have accepted that, but after seeing what Tune in a Tube can do I knew I didn’t have to. Of course the question remains, what does the velocity look like right now?

All the parts are clean, and that shouldn’t slow the rifle by any amount, but it also might not speed it up. Moly was used on those parts where the reduction of friction was important. I applied black tar to the usual places — mainspring and spring guide — but I kept the amount very light, so not too much velocity should be lost, if any.

Now I applied Tune in a Tube on top of the black tar, because I didn’t disassemble the rifle to apply it. What did that do? It got rid of the last bit of vibration, but what about the velocity? Only one way to find out!

Cocking effort and trigger pull

I will show today’s velocity test in the tables below as test 3, along with tests 1 and 2 from before. First, though, let’s establish the cocking effort and trigger pull — neither of which has changed much since I started the report.

The rifle cocks with 14 lbs. of effort. That makes it one of the lightest-cocking spring guns I have ever tested.

The trigger breaks with 3 lbs. 3 oz. of effort. The pull is single-stage and the break is crisp and clean.

RWS Hobbys

The first pellet I tested was the RWS Hobby.

Test 1…………………………Test 2……………………………Test 3
Shot…………….Vel…………Shot…………….Vel…………Shot………..Vel
1…………….….624…………..1……………….616…………1……………609
2…………….….615…………..2……………….613…………2……………612
3…………….….612…………..3……………….610…………3……………606
4…………….….618…………..4……………….607…………4……………618
5…………….….605…………..5……………….605…………5……………607
6…………….….619…………..6……………….604…………6……………620
7…………….….622…………..7……………….610…………7……………616
8…………….….600…………..8……………….616…………8……………610
9…………….….616…………..9……………….612…………9……………617
10………………615…………..10…………..….611…………10………..…616

Test 1…………………………Test 2……………………….Test 3
Avg……Spread…..FPE………Avg……Spread…..FPE…….Avg…….Spread….FPE
615……….24……..10……..…610……….11……..9.83……613……….14……..9.93

As you can see, there is not much change from either previous test. The rifle still performs much as it always has, though the extreme spread is still tighter than it was before any lubrication was applied.

RWS Superpoint

Next up were RWS Superpoints.

Test 1…………………………Test 2……………………………Test 3
Shot…………….Vel…………Shot…………….Vel…………Shot………..Vel
1…………….….552…………..1……………….546…………1……………546
2…………….….551…………..2……………….545…………2……………551
3…………….….559…………..3……………….549…………3……………556
4…………….….548…………..4……………….546…………4……………556
5…………….….532…………..5……………….548…………5……………548
6…………….….541…………..6……………….540…………6……………551
7…………….….550…………..7……………….541…………7……………545
8…………….….542…………..8……………….549…………8……………547
9…………….….549…………..9……………….552…………9……………554
10………………545…………..10…………..….539…………10……..……550

Test 1…………………………Test 2……………………….Test 3
Avg……Spread…..FPE………Avg……Spread…..FPE……Avg…….Spread….FPE
547……….27……..9.64………545……….13……9.57……550……….11……..9.74

JSB Exact RS

The last pellet tested was the JSB Exact RS.

Test 1…………………………Test 2……………………………Test 3
Shot…………….Vel…………Shot…………….Vel…………Shot………..Vel
1…………….….571…………..1……………….567…………1……………586
2…………….….572…………..2……………….570…………2……………577
3…………….….566…………..3……………….567…………3……………579
4…………….….558…………..4……………….564…………4……………577
5…………….….563…………..5……………….566…………5……………574
6…………….….563…………..6……………….568…………6……………565
7…………….….565…………..7……………….561…………7……………577
8…………….….568…………..8……………….563…………8……………571
9…………….….566…………..9……………….566…………9……………572
10………………561…………..10…………..….563…………10………..…569

Test 1…………………………Test 2……………………….Test 3
Avg……Spread…..FPE………Avg……Spread…..FPE……Avg…….Spread….FPE
565……….14……..9.52………566……….9…..…9.56……575……….21……..9.86

Discussion

The test reveals that the rifle is firing as good as ever. In some cases it’s slightly faster, but it’s still almost exactly where it was before I started tuning. So, what have I accomplished?

First, We now know beyond the shadow of a doubt that Tune in a Tube works well in this air rifle. It ends all vibration and doesn’t slow the gun down.

Next, we saw the insides of the rifle — how dirty and rusty the parts were after a half-century of sitting around. From the condition of the rifle we can safely assume it hasn’t been shot much. The wear and dirt are mostly due to the passage of time.

Next, we learned that the old way of tuning, namely a thin coat of black tar grease, isn’t as effective as Tune in a Tube. Black tar works, but it doesn’t go all the way. But when Tune in a Tube was applied on top of this thick grease, it smoothed the action the final amount. And it did it with no loss in velocity.

The rifle is now clean inside and out. It’s ready to continue testing, and accuracy comes next. While I will test it with that cheap BSA scope, I plan mostly to shoot it with open sights, so that will comprise the major portion of the test.

I checked back for a report of the .22-caliber Diana model 27 rifle (it’s actually a Hy Score 807) that is my most favorite air rifle of all and was unable to find a report that had velocity. As best I recall, that rifle is lubed with lots of lithium grease and puts medium weight pellets out in the lower 500s. It might be time to disassemble that one and give it a Tune in a Tube treatment as well.