Diana Model 27 Update

Since my last post, I have discovered several things about my new-to-me Diana Model 27.

1) It is indeed circa 1930's, most likely one of the first ones made, probably 1934 or 1935.

2) D. R. P. a. is indeed a patent declaration. D. R. P. stands for Deutsches Reichspatent. The letter "a" at the end stands for "angemeldet," which means registered or declared; it's the German equivalent of what in the U.S. would be "patent pending." Collectors call this version of the Model 27 the "D. R. P. version," because it is the only Model 27 to bear the D. R. P. stamp; the stamp was no longer used after 1945. Since mine says "patent pending," then I am the proud owner of one of the first D. R. P.s to ever be produced.

3) It is indeed .177 caliber, contrary to what I originally thought.

4) I acquired a rear sight for it, and a friend of mine found a spring and put it all in for me. The sight doesn't fit perfectly, which leads me to believe that perhaps it was made for one of the post-WWII 27's. But it's close, and I believe that with a little filing, it could be made to fit snug.

5) Since the sight isn't perfect, I haven't been able to try for groupings yet. But I did shoot it several times through the chronograph, and I have to say that I am quite pleased. This little gun averages around 620 fps with 8.2 grain Meisterkugeln pellets! That's excellent for a spring that is 76 years old!

All that is left to do now is to clean it really well, and finish the rear sight. When I can shoot groupings for it, I will post the results here.

My New Acquisition

I recently acquired this little gem: the Diana model 27 pellet rifle. I am not sure when it was made, because there are very few markings on the gun. The rifle has no safety catch whatsoever, and the stock is solid wood, and the mechanisms are all steel. There isn't a serial number anywhere on the rifle that I can see. Only the markings "Diana Model 27" and "D.R.P.a." The absence of both a serial number and of the safety catch lead me to suspect that the rifle might be pre-WWII, possibly 1920's or 1930's.

The barrel and the body have extremely slight surface rust in some areas, but these little blemishes do not affect the working of the gun itself. The same is true for the wooden stock; it has a myriad of tiny scratches and bumps, but these are cosmetic issues. The rear sight is missing; there is a little "shoe" for it, but it is as if someone took it off for some reason.

I was told by the dealer that the rifle "still shoots," although he did not elaborate any further. When I broke the breech, there was a light coating of oil on the breech seal. I have yet to shoot or chronograph the gun at all. In fact, I am not even positive of the caliber. From just "eyeballing" it, the rifle appears to be .22 caliber. (The hole looks a bit big to be .177, but I could be wrong.)

When I get some spare time, I plan to shoot it a bit, and see how it's held up over the years. Until then, here are some pictures of it. Please forgive the photo quality, these images were taken with my cell phone.

My "new to me" Diana model 27 air rifle.

There is a metal "shoe" where the rear sight should be.

Closeup; you can see some of the stock's dings and scratches.

The Goddess Diana.

D.R.P.a. (I believe this is a patent declaration.)

Diana P5 Magnum Second Range Test

Well, I went to the range yesterday, and here are the targets and results. I was going to shoot 25 of each pellet, but when I got to the Hyper Max pellets, they were shooting such tight groups that I had to shoot a lot more of them in order to see the true range of variability. (I ended up shooting 40 Hyper Max pellets.) I think you can see by these pictures that the Hyper Max is the true champion when it comes to accuracy; 58% of the Hyper Max pellets went through the same, quarter-sized hole. Only 40% of the Crosman pellets hit the same mark. Both targets were shot standing, at a distance of 7 yards (21 feet) with open sights, using a police-style, 2-handed grip.

25 shots with Crosman SSP 4.0 grain pellets @ 7 yards, police-style 2-handed stance.

About 10 of the 25 shots hit this quarter-sized area.

The red area is 3 inches in diameter.

40 shots with RWS Hyper Max 5.2 grain pellets @ 7 yards, police-style 2-handed stance.

Again, the red area is 3 inches in diameter.

About 23 of the 40 shots went through this quarter-sized hole.

I also chronographed these two pellet types. Here are the results. The first Hyper Max result was due to dieseling, I believe. I cleaned the barrel with an alcohol swab, then put a drop of silicone lubricant on the breech seal just before shooting the chronograph test.

Hyper Max 5.2 Grain: 718, 683, 663, 650, 639, 658, 644, 659, 656, 649

Average: 661.9 (662 fps)

Taking off the first 2 results: Average: 652.25 (652 fps)

Foot Pounds of Energy (FPE): 4.91 [Let's round this up to 5.0, since our last result was 5.17]

Crosman SSP 4.0 Grain: 787, 792, 789, 784, 782, 775, 785, 785, 785, 786

Average: 785 fps

Foot Pounds of Energy (FPE): 5.47 [Let's round this up to 5.5, just to be fair to the Crosman pellet.]

As you can see, while Hyper Max gives superior accuracy, the Crosman SSPs deliver more velocity and power.

785 vs. 652 = Over 130 fps faster!

5.5 vs. 5.0 = 10% more energy delivered.

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EDITORIAL NOTE: (This comment was added 03-19-2014, more than 2 years after the original post, by an older and wiser Scientific Airgunner!) The super-light-weight pellets (less than 5 grains in weight) should not be used, because they put additional and unwanted stress on the gun's mainspring; thus, despite the fact that SSPs deliver slightly more velocity and power, Hyper Max pellets are a better choice, because they aren't hard on your gun. However, I wouldn't shoot anything under 7 grains nowadays, because retained energy at the point of impact suffers greatly in lighter pellets. Look at the following post for details:  

http://thescientificairgunner.blogspot.com/2013/09/some-interesting-data.html

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You may have noticed the "flyer" at the bottom of the Hyper Max target, this is not an error of the gun, it is human error. I was at the gun range on a very busy day, and there were large caliber pistols going off all around me, and at times, that made it hard to concentrate. That particular shot came after a cease-fire had ended, and I kind of jumped when all the shooting commenced again.

Well folks, that's all for now. I hope to make the next post about my new Crosman Titan GP rifle. I have toyed around with it a little, but I haven't taken it to the range for any serious target work (yet!)

Pellet Data Chart For The Diana P5 Magnum

Data for Diana P5 Magnum

The other day, it occurred to me that it would be a good idea to have the data that I posted on other websites posted here as well, in case the other websites happen to either go away, change web hosts, or lose their data to an unexpected crash. So here it is, complete with bar chart. Each pellet (listed by brand and weight) was chronographed ten times, and then the average of those results was used to calculate FPE (Foot Pounds of Energy.)

Cabela's Ultra Mag (10.56 Grain) = 417, 410, 394, 408, 402, 416, 414, 418, 411, 421

(avg = 411.1) @ 411 fps = 4.11 FPE

Gamo Rocket (9.6 Grain) = 451, 450, 451, 457, 453, 454, 440, 434, 472, 445

(avg = 450.7) @ 450 fps = 4.32 FPE

RWS Meisterkugeln Pro Line (8.2 Grain) = 504, 504, 510, 505, 498, 512, 516, 510, 512, 499

(avg = 507) @ 507 fps = 4.68 FPE

Gamo Tomahawk (7.8 Grain) = 531, 506, 526, 533, 525, 509, 503, 537, 527, 524

(avg = 522.1) @ 522 fps = 4.72 FPE

RWS Hypermax (5.2 Grain) = 671, 667, 664, 673, 669, 668, 663, 670, 675, 675

(avg = 669.5) @ 669 fps = 5.17 FPE

I find it interesting that the FPE was greatest in the lighter pellets. It would seem that although mass plays a large factor in the hitting power of a projectile, velocity can have a pronounced effect as well.

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EDITORIAL NOTE: (This comment was added 03-20-2014, more than 2 years after the original post, by an older and wiser Scientific Airgunner!) The Hyper Max pellets WILL get you close to the 700 FPS that is promised on the box, and they weigh JUST ENOUGH that they aren't hard on your gun. (Pellets that weigh 4.9 grains or less will place additional stress and "wear & tear" on your spring; pellets that weigh 5.0 grains or more won't. That's why RWS makes their "light pellet" heavier than most other manufacturers.) However, I wouldn't shoot anything under 7 grains nowadays, because retained energy at the point of impact suffers greatly in lighter pellets. Look at the following post for details:  

http://thescientificairgunner.blogspot.com/2013/09/some-interesting-data.html

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Initial Review Of The RWS Diana P5 Magnum (RWS Model 5G Magnum)

Hello, and welcome to my blog. This blog is about the scientific method: I gather data on the performance of various airguns, and analyze it. Then I do it again and again. Each time, I compare the new data to all of the previously gathered data, to see if there are any noticeable trends, similarities, or differences. I also use data gathered from other sources (i.e., other reviews posted on other blogs) so as to provide the reader with a "second opinion," from an unbiased, unrelated party. All data from secondary sources will be properly credited and linked.

EDITORIAL NOTE: (03-21-2014) I have revised this post somewhat, deleting links that are no longer active, and making the occasional comment as well. Revisions will appear just like this, in light red text.

The first review that will appear here is my review of the Diana P5 Magnum Pistol (RWS Model 5G Magnum.) The second part is in parenthesis, because the box that the pistol came in was marked "RWS 5G Magnum," but the top action of the pistol clearly cites the model number as the "RWS Diana P5 Magnum." I am a librarian by profession; when cataloging books, a librarian goes by two main sources when looking for the proper title of a book: the title page, and the title page verso. ("Title Page Verso" simply means "the back of the title page.") What the dust jacket or book cover says is irrelevant (and often quite different from the official title!)

The RWS Diana P5 Magnum Pistol, with cocking extender attachment.

Thus, using the same principle, what is stamped on the gun supersedes whatever the box says. But since many people refer to it as the 5G rather than the P5, I chose to include the box citation in parenthesis, to indicate that it is an unofficial designation for the P5.

On other forums, I go by the handle HCAirgunner. The HC stands for "Hard Core," in reference to the extensive research that I perform on each gun before I purchase it, and to the rigorous testing that I put the gun through afterwards.

Here is the Pyramyd Air blog post about the P5 Magnum pistol:

http://www.pyramydair.com/blog/2005/11/diana-p5-magnum-air-pistol-from-rws.html

as well as this re-printed article:

http://www.pyramydair.com/article/Fast_and_accurate_Testing_the_RWS_Diana_5G_Magnum_P5_pistol_March_2009/58

It should be noted that the P5 is a discontinued model, having been replaced by the LP8.

You can see a review of the LP8 (also by Pyramyd Air) by following this link:

http://www.pyramydair.com/blog/2009/09/rws-model-lp8-magnum-part-3.html


I believe (but am not 100% certain) that the following reasons led to the discontinuation of the P5:

1) There was a safety recall of the P5 in April of 2008. Details are here. EDITORIAL NOTE: (03-21-2014) One of the P5 pistols I originally bought was part of this recall; Umarex fixed it quick at no cost, and I haven't had a problem since.

2) The gun had no scope rail, forcing those who would want to add one to modify the gun with machine tools.      EDITORIAL NOTE: (03-21-2014) I have now done the same to my P5 pistols. Look here.

3) The safety mechanism was awkward, and non-ergonomic for some people to operate. (Personally, I found the safety mechanism quite user friendly and easy to operate, but I seem to be in the minority.)

4) The grip that came standard with the pistol was a right-handed groove type, which made the pistol cumbersome and difficult to use for left-handed shooters. (Personally, I agree; I think that such grips ought to be sold as optional equipment, and that ambidextrous grips should come standard.) EDITORIAL NOTE: (03-21-2014) I have solved this problem by ordering the left handed grips, and then swapping out the right sides, which creates an ambidextrous grip, making the gun considerably more comfortable to shoot.

5) Some people found it hard to cock, and worried about breaking the fiber optic sights on the muzzle break. (Me too, but I solved the problem by buying the cocking extender from Umarex. Now, cocking the pistol is fast and easy, and I no longer run the risk of fouling the sights.)

6) Most people believe that the 700 fps claim is unattainable. If you have already read my posts elsewhere on this blog, then you know that the gun does approach 700 fps (averaging about 669 fps with the RWS HyperMax 5.2 grain pellets.)

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EDITORIAL NOTE: (03-21-2014) The Hyper Max pellets WILL get you close to the 700 FPS that is promised on the box, and they weigh JUST ENOUGH that they aren't hard on your gun. (Pellets that weigh 4.9 grains or less will place additional stress and "wear & tear" on your spring; pellets that weigh 5.0 grains or more won't. That's why RWS makes their "light pellet" heavier than most other manufacturers.) However, I wouldn't shoot anything under 7 grains nowadays, because retained energy at the point of impact suffers greatly in lighter pellets. Look at the following post for details:  

http://thescientificairgunner.blogspot.com/2013/09/some-interesting-data.html

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As for accuracy, the P5 performed well at the shooting range (the masthead picture for this blog is a picture of the P5's initial groupings,) however, I still have work to do in this area, because I believe that A) my P5 isn't sighted in perfectly yet, and B) I am not the world's best marksman by any stretch of the imagination. The next time I visit the shooting range, I intend to shoot a lot of targets, and the results, of course, will be posted here.

That's all for now. I hope you enjoyed reading my initial assessment of the Diana P5.