by Tom Gaylord
Writing as B.B. Pelletier

Beeman R10
Beeman R10.

Part 1

History of airguns

This report covers:

  • Start
  • Scope base off
  • Tip 1
  • Mainspring
  • Remove piston
  • Sleeved piston
  • Threaded spring tube
  • Breech seal
  • Cleaning
  • Piston seal
  • Tuning strategy
  • Trigger
  • Insert the piston with the new Vortek seal — tip 2
  • Last thing — the trigger box!
  • Final assembly
  • Summary

Today I disassemble the Beeman R10 and install the Vortek PG3 tuning kit. I installed one of these in the Air Arms PG3 SHO tuning kit in an Air Arms ProSport last year and the results were very positive. But this R10 is a different rifle in many ways, and I will cover that today as we go.

I am going to show you all the differences and nuances of the R10, but I can’t show everything about disassembly. If you want to see that read the 13-part series titled Spring gun tune. That was about a Beeman R1, but most of the steps are the same for the R10. I will address the ones that aren’t.

Start

The barreled action was out of the stock, so the first step was to remove the Rekord trigger and safety. To remove the trigger, drift out the two pins that hold the trigger unit in the end cap.

Beeman R10 trigger out

When the two pins are tapped out the trigger unit is free to be removed.  Once the trigger is out the safety and spring slide out of the end cap.

When I saw the trigger I thought that this rifle has never been apart, because all the factory grease remains on the trigger parts No tuners I know would leave all that grease on those parts. It serves no purpose.

Before someone asks the obvious question of why Weihrauch puts the grease there if it serves no purpose, let me tell you that you have never seen the assembly of an airgun if a factory. It’s fast! The workers are told to squirt a little grease here and there and they do. Some do more and others less. In some countries where it is very hot perhaps the grease melts and runs over the parts. In others it ends up like this. That’s just the way it is.

Some airguns are dwesigned to need much less grease. The Air Arms TX200 Mark III is an example. So less grease is applied and the lubricity of the parts does the rest.

Scope base off

Next I had to do something that’s unique to the R10. The scope base is attached to the end cap by two screws. But the base is also attached to the spring tube by a flange, so the base must come off before the end cap can be removed. And there was a scope stop attached to this scope base that had to come off first.

Once the two screws are out the scope base should slide forward and come out of the spring tube. It’s held in place by a flange that I will show you. This one was stuck, though, by what turned out to be hardened grease. That’s more of an indication that the gun has never been apart. So I partially unscrewed the end cap with the scope base still on the rifle.

Tip 1

The R10 end cap unscrews from the spring tube. When the gun hasn’t been apart for a long time the cap can be hard to start turning. Once the trigger is out of the gun there is a large slot in the end cap where the handle of a crescent wrench can be inserted and used to start the end cap turning. I use the rounded end of a crescent wrench because it is rounded and will not damage the sharp edges of the trigger slot in the end cap. I also use it to tighten the end cap at the end of assembly. I will also grease the end cap threads so it’s easier to remove next time.

Beeman R10 end cap
I have started to unscrew the end cap. The scope base is still attached to the spring tube, but the end cap screws are out so the cap is free to turn.

You can unscrew the end cap by hand until there are 3-4 threads remaining. Then put it into the mainspring compressor and keep tension on the cap as you slowly unscrew it.

Beeman R10 end cap unscrewed
The end cap is unscrewed all the way, but the mainspring is still pressing against it.

I had no idea of how much pretension the R10 mainspring had, but the compressor was set to allow a long one. Good thing, because it turned out there are three inches of pretension on the spring — one is taken up by the end cap threads and the spring has the other two!

Beeman R10 mainspring relaxed
The mainspring has finally relaxed! As you can see, there is a lot of pretension on this spring!

Mainspring

With the end cap off, the mainspring and spring guide could be removed. This spring is unlike any I have ever seen in a Weihrauch product. What I thought was lube on the spring coils was actually just the shiny metal. There was almost no lube on the mainspring, which is consistent with other Weihrauch airguns I have disassembled.

The spring is canted at both ends — rather visibly at one end. This was the reason why there was some vibration when the rifle fired

Beeman R10 mainspring canted
The mainspring was canted noticeably — especially at the end that went over the spring guide.

Once the mainspring was out I could move the scope base forward until it freed up and slid out of the spring tube. 

Beeman R10 SCOPE BASE
Here you see the scope base and the slot in the spring tube where it fits. The square piece on the left underside of the scope base is a flange that slots into the spring tube.

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Remove piston

With the mainspring out the cocking shoe is removed from the piston and the piston is slid out of the rifle. There was nearly no lubrication on the piston, either, which leads me to believe that the gun had never been disassembled. If it was, whoever did the work did not lubricate it very well.

Beeman R10 piston
The piston was dry.

Sleeved piston

One R10 quirk is that the piston is sleeved. That reduces the clearance between the piston and the mainspring. The Vortek kit cannot be installed with the sleeve in place, so it has to be removed. There is a small hole at the top of the sleeve to assist you in this task.

Beeman R10 piston sleeve
The piston sleeve has a hole at the top (arrow) to assist in removal.

Beeman R10 piston sleeve 2
This view of the bottom of the piston shows the sleeve better.

Beeman R10 piston sleeve 3
The sleeve is sliding out.

Beeman R10 piston sleeve 4
The sleeve has been removed.

Threaded spring tube

Let me show you the threads in the spring tube. Remember I said that threading the tube was risky? Let’s see why.

Beeman R10 threaded tube
This is the threaded end of the spring tube, where the end cap screws in. There’s not a lot of extra material for leeway.

Breech seal

I was also sent a new breech seal for the rifle. The one that was in the gun looked okay, but when I went to remove it, it broke apart. The Weihrauch seal looks like an o-ring in the gun, but it’s three times as tall and is specially made for their rifles. This replacement seal seemed to be the same tough stuff that the Vortek piston seal is made of.

I’ve never seen a Weihrauch breech seal break apart that way, but I have seen a lot of other airgun seal break apart. So it’s a good thing it was changed. It took me some time to pick out all the broken pieces.

Beeman R10 breech seal
When I tried to pick out the breech seal it crumbled into pieces.

Cleaning

At this point I cleaned the rifle and its parts, plus I looked for any burrs to remove. I found no burrs, and the interior of the spring tube wasn’t that dirty. I use a long dowel with a piece of paper towel wrapped around one end and held on by a rubber band. I usually dip the towel into alcohol, but this time I used acetone, which cleans even faster.

The piston needed to be cleaned inside and out. And I cleaned the head of the piston after removing the old piston seal. The new seal needs to be on a clean piston.

Piston seal

The old piston seal was still in good shape, unlike the breech seal, but since the Vortek kit comes with a new piston seal, I put that one on. It’s made of extremely tough synthetic material which proved a real blessing during assembly.

Tuning strategy

At this point in any tune my experience takes over and I do things my way. When I tuned the Air Arms Pro-Sport I put a thin coating of Tune in a Tube on the mainspring of that PG3 kit, to cut the vibration. The Vortek kit is supposed to dampen all vibration, but I didn’t want to take a chance. But Gene Salvino said in the comments to Part 1 of this report that the Vortek lubricant that is provided is slicker than TIAT, so I decided to give it a try. At worst I would have to open the rifle again to fix my mistake if the kit vibrated.

Here is what Gene said to reader Chris USA,

“DO NOT use TIAT in a Vortek . His [Vortek’s] grease is a synthetic based grease that is very slippery and will not gum up in the cold weather . Zero benefits , the guides shield the noise anyways . TIAT is for high powered guns with factory guides with factory drop in tolerances , the Vorteks are very tight .”

Beeman R10 Vortek kit
The Vortek kit contains a small container of special lube that’s supposed to be much slicker than TIAT.

I lubed the piston seal, the piston body, inside and out, including the central rod that connects to the trigger with the Vortek grease. I lubed the front of the mainspring generously because I couldn’t get the white rear spring guide off the mainspring to lube there. I figured when I cocked the rifle that part of the spring would get some grease.

I didn’t lube the inside of the rifle’s spring tube, which I normally do with moly. The parts that generate friction in the Vortek kit are all held by synthetic parts that have a low coefficient of friction, so I figured Vortek knows what they are doing.

Trigger

I spent some time cleaning the factory grease out of the trigger. Yes, an ultrasonic cleaner is probably the best way to do that, but I don’t have one. So it’s cotton swabs and paper clips for me.

When I had removed as much grease as possible, I then lubed the sear contact point and the piston rod catch with moly grease.  Before doing that I cocked the trigger by pressing down on the rear if the long piston rod catch until the sear caught. I could then examine the sear contact area with a loupe. You will remember that  I told you in Part 1 that this trigger is adjusted perfectly. I don’t want to do anything to mess it up.

Beeman R10 trigger unit
To check the sear contact, cock the trigger by pressing down on the back of the piston catch lever (arrow shows where it is inside the black trigger box) until the sear catches. The sear contact inspection hole is at the lower left.

Beeman R10 sear
The sear contact is enough to be safe, as this trigger is adjusted. This is about a 10X magnification. The factory grease has not yet been removed. 

Insert the piston with the new Vortek seal — tip 2

I tried and tried for 20 minutes to get the new Vortek piston seal into the spring tube. No matter what I did that seal was not going in past the threads. The seal has a small lip on the back that just will not pass the threads in the spring tube.

Beeman R10 piston seal
That small lip on the rear of the Vortek piston seal would not go past the threads in the spring tube.

Finally, after fiddling with the piston for 20 minutes, I decided to “thread” the piston seal past the threads. In other words, to screw the piston into the spring tube. It worked! This kit also works on a Beeman R9, but because its spring tube isn’t threaded, you will not encounter this same difficulty.

It took me about 5 minutes to thread the seal into the tube, but once past the threads the piston slid into the spring tube the rest of the way. It was by no means easy to move the piston inside the tube, but it did move, once the threads were passed. The seal appeared to suffer no damage from being installed this way. That’s what I meant about its toughness.

Once the piston was inside the tube and connected to the new cocking shoe that I lubricated with the Vortek grease, I was able to slide the entire mainspring with its guides into the spring tube. When it was shoved all the way in only about 3/4-inch of the parts stood out, compared to the two inches with the factory spring.

Beeman R10 spring installed
The Vortek spring and guides go into the piston much farther than the factory parts.

Last thing — the trigger box!

You may not know this and you need to learn. Beeman told the owners of R-series rifles not to over-tighten the rear triggerguard screws on their rifles. This is because Weihrauch used to just punch a hole for that screw into the bottom of the trigger box and then thread the metal flanges that were displaced by the punch. Those threads are extremely tenuous! I want you to see them.

Beeman R10 trigger box
There are the threads that hold the rear triggerguard screw. Don’t over-tighten it! 

At some point after this rifle was made, Weihrauch replaced this method with a small nut that slips into the trigger box, but even that is small and not that strong. Just don’t over-tighten that screw!

Final assembly

The R10 went back together the way it came apart. Again I remind you to read the 13-part Spring gun tune report to see the details.  I have given you all the ones where the R10 differs. Once the barreled action was together and was back in the stock, the rifle was cocked and fired to prove everything worked as it should. It did!

The firing cycle is now completely dead and free from vibration. This is as good a tune as I could ever hope for. This Vortek kit works exactly as described and does a remarkable job. It’s a $400 tune for $90, if you do the work. I will say that a mainspring compressor is needed because those fine threads on the end cap are hard to get started.

Summary

I can do a job like this on an R1 in about 45 minutes. This R10 took 3.5 hours to do the same things. Part of that was because the rifle may never have been apart and part of it was the special design of the R10. The Vortek piston seal made installation of the piston take longer, but if you screw the piston in like I mentioned you’ll avoid the time it took me.

So — what did the Vortek kit do for this R10? To find that out you’ll have to read the next part of the story.