Beeman R10: Part 1
by Tom Gaylord
Writing as B.B. Pelletier
This report covers:
- This R10
- History of the Beeman R9 and R10
- Tap the cap
- What about this R10?
- The R10 came in both standard and deluxe versions
- Thin spring tube
- Cocking shoe
- Velocity with JSB 8.44-grain
I wrote a 6-part report about the Beeman R10 in 2017-18, but this one will be different. The rifle I reported on three years ago was actually a Weihrauch HW85 that was the basis of the Beeman R10, and I bought it because it had been super-tuned. Not only is it lubed to perfection, but some internal parts like the spring guide were made for it so there is no tolerance in the powerplant. If you read the series, especially Part 1, you will learn that this rifle was tuned by Bryan Enoch, reader David Enoch’s brother. When I shot it at the Malvern, Arkansas, airgun show I was impressed by how smooth it was. I made one of those, “If you ever decide to sell…” kind of offers and David (or Bryan — I really didn’t know whose rifle it was) took me up on it about a year later.
What I am looking at today is a genuine Beeman R10. The largest difference between the two rifles is the forearm of the R10 is about two inches longer than the forearm on the HW85. Other than the markings on the guns, I don’t think there is any other difference.
This R10 belongs to a reader of this blog — Jim M. At the Texas airgun show several years ago he asked me if I would tune one of his air rifles and after some discussion we settled on this one. The rifle is not in stock trim. Both the front and rear sights have been removed, there is a Beeman muzzle brake in the front of the barrel and I can see through the cocking slot that someone has lubricated the mainspring after the gun came from the factory.
Jim wants me to install a Vortek PG3 HO tuning kit into this rifle. PG stands for Precision Guide and the three means there are three guides for the mainspring. HO stands for High Output — meaning power. This is a high-power kit that will produce more power than their conventional 12 foot-pound kit, though it may not produce as much power as the Beeman factory mainspring. More on that in a bit.
This kit is made for the HW95, which also is the Beeman R9. It will fit the R10/HW85, though, because of the history of the two Weihrauch models.
History of the Beeman R9 and R10
There used to be an airgun manufacturer based in Erlangen, Germany. Their name was Bayrische Sportwaffenfabrik, or BSF, and they made many fine spring-piston airguns. Their most powerful breakbarrels were the BSF S55/S60/S70 that were essentially all the same powerplant in stocks with varying degrees of finish. I have reported on the S70 in this blog, including a long series on how to bend an airgun barrel where the S70 was the subject. Unfortunately BSF went out of business in the 1980s. Weihrauch purchased all or a lot of their inventory that included finished airguns, and lots of parts in-process.
Weihrauch made many different models of air rifles to exhaust the BSF parts, including a Marksman 55 and 70 that were similar to the BSF rifles but were engineered to accept the Rekord trigger instead of the BSF trigger. Another rifle they made from those parts was the HW85 that was also the basis for today’s subject Beeman R10.
In the early 1980s Weihrauch benefitted from the design input of Dr. Beeman who had computer-modeled the performance of a new breakbarrel air rifle he wanted. As far as is known this was the first computer-aided design of a production airgun. Beeman had long wondered why the big HW35 was not more powerful, and his computer model revealed the reason — the piston stroke was too short.
Weihrauch saw great potential in the new design and agreed to build it if they could retain the rights to the gun under their own name, as well. That rifle was the Beeman R1, that Weihrauch branded as the HW80. Because the R1 used a wood stock with a longer forearm, the HW80 was produced first, since a source of wood had to be established for the longer stock. That might sound like a trivial thing to most people, as in, “Why not just cut the wood longer?” But until you understand the full ramifications of the production world you can’t appreciate what sort of time delay a two-inch longer stock can bring.
At any rate, the R1/HW80 design accomplished exactly what Dr. Beeman was hoping for — a .177-caliber spring piston air rifle capable of a muzzle velocity of 1,000 f.p.s. It didn’t happen in the first year of production, but by year two HW had learned how to lubricate the powerplant to get that speed. And a year after that Dr. Beeman came out with a softer (weaker) mainspring made from some high-tech steel that, along with a new tightly-fitted piston seal and a new lubricant, got the velocity over 1,100 f.p.s. How about that — it was easier to cock as well as more powerful!
But the R1 wasn’t the only rifle Weihrauch was looking at. They had all those BSF parts and had already made some spring rifles of their own. So what became the HW85 and R10 flowed out of that. Dr. Beeman’s computer modeling showed the Weihrauch engineers that the length of the piston’s stroke, and not its diameter was tantamount to developing greater power. So Weihrauch took the smaller BSF spring tube and gave the piston a longer stroke and the HW85/R10 was born. It was more powerful than the R1 yet weighed over a full pound less. The forearm was slender compared to the R1and the resulting rifle was a step forward the evolutionary trail of spring-piston airguns. Except for one thing.
Tap the cap
Robert Beeman was ever-so-fond of his R1 end cap that restrained the mainspring. It was threaded into the thick R1 spring tube, which made servicing the powerplant a breeze. In those days we didn’t use mainspring compressors — we restrained the heavy end cap with our generous bellies, while the muzzle was safety pressed into the inside of a shoe or sandal. In fact, it is the Beeman R1 that caused many airgunners, including your stout author, to develop a generous midriff, just to assist in powerplant disassembly! (insert smiley emoji here)
So, the R10 got a threaded end cap, too. Only, with its much thinner spring tube, the danger of ruining the spring tube and creating scrap while threading rose quite high. It was soon realized that a better way to fit the end cap was needed. Enter the R9. The R9 is an R10 without the threaded end cap. That’s why the Vortek tuning kit will fit both air rifles. It’s also why an R9 can achieve the same velocity as the R1 and still weigh a pound and a half less.
To sum all of this up — the R1 proved that a longer piston stroke was the key to more power. The R10 took that longer stroke one step farther and got greater velocity with less size and weight. And the R9 made the whole thing produceable.
R10 production ended because that rifle was too expensive to produce, due to excessive scrap. The R9 that replaced it is the same rifle in a form that’s easier to make.
What about this R10?
Now that were are up to speed on the model, what can I tell you about this particular R10? It’s a .177 caliber rifle. They also came in .20 and .22 caliber. Dr. Beeman fancied the .20 caliber as the best of all worlds, but in the end the market didn’t follow him. However, the Weihrauch website says the HW85 is still being produced in .20 caliber, as well as .25 caliber.
The R10 came in both standard and deluxe versions
The R10/HW85 came in a deluxe version with a longer barrel and a checkered pistol grip as well as a standard model with a shorter barrel (16.14-inches/410mm) and no checkering. The one I’m testing is the deluxe.
Thin spring tube
The spring tube is so thin that Weihrauch could not cut 11mm scope grooves into it without weakening the tube. So they screwed on an external scope base and someone has added a Beeman scope stop to that.
The R10 spring tube is too thin to accept grooves, so an external scope base was screwed on.
The rear sight is not present and a proper Beeman plate sits in its place. The front sight was removed and a Beeman muzzle brake was added. That extends the 19.7-inch (500mm) barrel by just over an inch, making the already easier cocking even lighter. An R1 that’s been broken in would require 36 lbs. of force to cock. This R10 needs 24 lbs. to cock which is almost exactly where it should be. The Beeman catalog says 25 lbs. is what it should be, though the muzzle brake gives us that extra inch of leverage.
The Rekord trigger is set to require 13 oz. for the first stage, with a clean break at 1 lb. 8 oz. for stage two. That is about as good as it gets, so the only thing I might do is lubricate the trigger pivots and parts. Yes a Rekord can be adjusted lighter, but I don’t need it any lighter. This is perfect for me.
I noted with interest that among the parts Jim sent for his rifle there is a “new-style” Beeman R9/R10 cocking plate — a part I call the shoe. It fits the end of the cocking link and sits in the piston’s slot to push the piston back when the barrel is broken open. So I examined the shoe that was on the rifle and, while it did not seem to be broken, it also did not fit the end of the cocking link very well. The connection appeared very open and loose. And the new-style plate or shoe that Jim sent appears to correct this flaw — if it is a flaw.
New-style cocking plate.
Jim bought the rifle in September of 2016. He chronographed it to see how healthy it is and he recorded an average of 846.5 f.p.s. that I will round up to 847 f.p.s. with JSB Exact 8.44-grain domes. His extreme spread was 7.46 f.p.s that I will round up to 8 f.p.s. He never shot it for accuracy, so it’s a much a mystery to him as it is to the rest of us. I thought I would test its performance before I do anything to it.
Velocity with JSB 8.44-grain
My chronograph recorded the following velocities for the JSB Exact 8.44-grain dome.
9………..785 — Oh, oh!
After shot 9 the rifle would no longer cock. I could tell that the cocking link was no longer connected to the piston, so I took the action out of the stock and indeed that was the case. The cocking shoe appears not to be broken, but the link has come out of the shoe. No doubt that is why I was sent the “new style” cocking plate or shoe.
The cocking link popped out of the cocking shoe or plate. I could just snap it back in and continue shooting, but I think it’s time to fix this old gal!
Jim told me what he wants is a smooth-shooting rifle. Power is of secondary concern, as long as the rifle is smooth. So, smooth is what I will go for. The Vortek kit should give all the power that’s needed, and most of the smoothness. I will just tweak it as I go.
This will be your chance to watch another vintage Beeman/Weihrauch rifle get overhauled and tuned. Most of the work will be done by the excellent drop-in kit, but old BB may have a trick or two to add. This should be an interesting series!