by Tom Gaylord
Writing as B.B. Pelletier

Diana 27S
Diana 27S.

A history of airguns

This report covers:

  • Carel
  • Diana 27S
  • Anti-beartrap
  • Description
  • Dimensions
  • Sights
  • Ball bearing sear
  • History
  • Parts interchange
  • Summary

This report is one I wanted to write months ago, but after all I wrote about reader Michael’s Winchester 427 and my own Diana 26 and Diana 35, I thought I had better let vintage Dianas rest for awhile.


I purchased this Diana 27S along with the Diana 26 and Diana 35 I have just mentioned from reader Carel of the Netherlands. He gave me a fantastic deal on three air rifles that are quite uncommon in the US. The 35 is the most common of the three, but Carel had a very early one that was different than the one many Americans have seen, so it was just as uncommon to me as the other two.

Diana 35
The Diana 35 I got from Carel is a very early one that we don’t often see in the U.S.

I was able to tune the 35 to be a smooth shooter and an easy cocker — something that you don’t see with run-of-the-mill Diana 35s (and Winchester 435s/Hy-Score 809s/Beeman 200s that are all the same rebranded models). That was a 6-part series that’s linked above.

Diana 27S

And now we come to the subject air rifle — the .177-caliber Diana 27S. What is it? Well, there is very little written about this model so I’m going to expand your horizon just a tad. There are some subtle refinements on this scarce Diana model.

In the UK the German Diana is called the Original Diana, because the Milbro company of Scotland received the rights to produce and sell Diana airguns as war reparations following WWII. In the 1981 edition of The Airgun Book, author John Walter says the Original Diana 27S comes with “an automatic trigger-blocking safety”. I thought, “Oh, no — not one of those!” But don’t fret. He didn’t mean what you think.


What Walter meant was the 27S has an anti-beartrap device built into it, unlike the standard model 27 that you can close when it’s broken open by pulling the trigger (restrain the barrel when doing this!). There is no separate safety lever on the 27S. But the barrel has to be closed in order for the trigger to work, so Walter is correct in what he says, but the term anti-beartrap is used more commonly for this feature today. We will take a closer look at the parts that support this function when we go inside the rifle. Yes, we will be going inside!


The Diana 27S is a conventional breakbarrel spring-piston air rifle, but it differs from the 27 in a couple obvious ways. The triggerguard is very angular The forearm is also squared off and the end is cut on an angle instead of being rounded like the forearm end of a standard 27. The butt has a thin rubber pad that’s separated from the wood by a white line spacer. On a conventional model 27 there is just a red rubber button at the top of the wooden butt to help the rifle stand on its butt without slipping.

Diana 27S logo
The Diana logo shows Diana dropping her bow for a rifle. As you can see, there are flecks of rust in the blue. Ballistol and 0000 steel wool will handle them.

Diana 27S butt pad
The 27S has a whole butt pad, where the 27 just has a rubber button.

My .177-caliber 27S rifle weighs 6 pounds 10 oz., which is one pound one ounce heavier than my .22-caliber Diana 27 (Hy-Score 807). The .177 caliber adds a little weight because the barrel, having thicker walls, weighs a little more. Also the forearm of the stock is a trifle wider and the cocking slot is shorter because the two-piece cocking link is articulated and therefore doesn’t need the longer slot. More wood means more weight. In theory this makes the stock stiffer, which should help to reduce vibration a little, but in this day of Tune in a Tube, spring gun vibration is a thing of the past.

Diana 27S cocking slots
As you can see, the 27S (top) has a much shorter cocking slot than the 27 shown below. You can also see that the forearm is slightly thicker.


The 27S measures 42.25-inches overall. The barrel is just under 18 inches. The pull measures bang-on 13-inches.


The sights on this rifle are similar to those found on the 27. The front sight is a globe with a fixed tapered post and looks exactly the same as the front sight of a 27. The rear sight adjusts in both directions, but is mostly metal instead of the earlier plastic sight found on the 27. It is the sight that is often called the upgraded all-metal rear sight. And although I have never noticed, later model 27s may also have a rear sight like this.

This sight is a good change because the plastic sights used to break all the time. I think the plastic becomes more brittle with time.

There is also a raised base for a peep sight. It’s tack-welded to the spring tube. Some may think of it as a scope base, but its real purpose is to accept the Diana peep sight that’s made for many of their sporting air rifles.

Diana 27S rear sight
The Diana 27 rear sight is mostly plastic.

Diana 27S rear sight
The Diana 27S rear sight is mostly steel.

Ball bearing sear

This rifle has the ball bearing sear. When we go inside we will see how the anti-beartrap device interacts with it.


It’s easy to get confused in researching the Diana model 27 because there were several versions of a 27 before World War II. However, those rifles are entirely different and their parts do not interchange with the post-war rifles we are discussing.

The biggest functional difference between the straight 27 post-war model and the 27S is that anti-beartrap device. The biggest obvious differences are the two-piece articulated cocking link and the square triggerguard.

The post-war Diana 27 began production in 1951. The 27S started in 1973. According to Walter, the 27S was pricy. I have no other data to support that, but assuming he is right and the 22-year head start the 27 had it’s no wonder there aren’t as many 27S rifles around.

Parts interchange

The Blue Book of Airguns currently goes out of its way to tell you that, “The model 27L, 27A, 27E, 27S and 27 air rifles appear somewhat similar but they are completely unrelated with virtually no common parts.” Well — that’s just wrong! If you really study the listings (pp. 390 and 391) you will discover that sentence that is repeated several time refers to the PRE WAR model 27s, only! Somebody got trigger-happy with the cut-and-paste function and goofed-up the entry. Several of us are now editing the Blue Book for the next edition and I plan to fix this entry.

The model 27 and 27S rifles that I am writing about today are very similar and share a lot of common parts. The anti-beartrap is one big difference and the articulated cocking link, the stock and the rear sight are the others, though the rear sight may have been used on 27s built after 1973. Until I get inside and see what’s there that’s all I can say.


So, what do we have in the Diana 27S? I think I can sum it up quickly. It’s an updated model 27. Diana continued producing the 27 until 1987 and the 27S was probably officially terminated at the same time, though a lower sales volume probably ended production somewhat earlier. That’s just my guess, because there is very little solid data on the model.

My plan is to conduct the conventional tests with the rifle and then strip it down and see what lies beneath. It currently buzzes when it fires. As long as I can make it better, why not?