Checking out a Diana RWS 34P: Part 2

by Tom Gaylord
Writing as B.B. Pelletier

Part 1

Diana 34P
The Diana RWS 34P is a classic breakbarrel spring-piston air rifle.

This report covers:

  • The breech
  • Velocity JSB Exact RS
  • RWS Superdome
  • RWS Hobby
  • Firing behavior
  • Cocking effort
  • Trigger pull
  • Next
  • Next
  • Evaluation

Today we are back with reader Geo791’s Diana 34P, and we’re looking at the velocity. This is a .22, and a fresh one should produce velocities and power in the same neighborhood as the Beeman R1, but not quite as powerful. George was never concerned about the power of his rifle — only the accuracy that he thought was sporadic. But I do plan to tune his rifle with a Vortek kit that was donated by Vortek for this series, so either way, he wins.

Power has little affect on accuracy. Sometimes if a shot cycle can be smoothed a lot you may see tighter groups, and other times if a weak powerplant is restored to new or better the airgun might shoot better. But typically I tell people that accuracy lies in the barrel and not in the tune. However, just because I say it doesn’t make it so. We shall see.

The breech

Before we start I want to show you the breech of George’s rifle. Diana has long been criticized for having an angled breech that deforms the lower half of the pellet skirt when the barrel is closed. Well, on George’s rifle Diana has corrected this.

Diana 34P breech
The breech on this Diana 34P is specially counterbored to allow the pellet to sit deep and miss getting deformed when the barrel closes. The top of the breech counterbore (on the left in this picture) is deeper than the bottom, to make the pellet sit parallel to the bore.

Diana 34P breech pellet
A JSB Exact RS pellet sits deep in the breech. Other pellets sit higher, but they are all still lower than the breech face.

I checked my Diana 34P breech, after seeing this. My rifle is a .177, but there is no evidence that this special “deep seating” breech has been cut in the barrel of my rifle. This is something new.

George complained that some pellets fall out of his breech when the barrel is closed. I found that if I seated each pellet deep into this new counterbored breech with the tip of my finger, nothing fell out! The pellet just has to go in a little farther to be grabbed by the rifling. I have never seen this feature on a 34 before, so I think the new owners of Diana have listened to complaints about pellet deformation and made some changes.

Velocity JSB Exact RS

The first pellet we will test is the JSB Exact RS dome. At 13.43-grains they are light enough to be fast, yet can be very accurate in some airguns. In this 34P they averaged 639 f.p.s. The spread went from a low of 629 to a high of 654 f.p.s. That’s a spread of 25 f.p.s. That much difference is on the high side of normal for a spring gun. At the average velocity they generate 12.07 foot-pounds of energy at the muzzle. That velocity and power are both on the low side for a .22-caliber Diana 34.

RWS Superdome

The second pellet I tested was the RWS Superdome, and what a difference I saw! This 14.5-grain pellet averaged 701 f.p.s., for 15.83 foot-pounds at the muzzle. That’s spot-on what I expected from a 34! The low was 691 and the high was 707 f.p.s. — a spread of 16 f.p.s. So, the spread is much tighter, as well.

I think George’s rifle is in fine shape. Of course we will see for ourselves when we go inside to do the tuneup. But the chrono numbers look good. This result tells me one more thing. Maybe JSB Exact RS pellets are not well-suited to this rifle! They generate a lot less power and they have a much larger velocity spread. This is why owning a chronograph is so valuable, because it allows you to look inside a gun’s operation to detect small things like the difference between two pellets.

RWS Hobby

The last pellet I tested was the 11.9-grain RWS Hobby. They averaged 736 f.p.s. The low was 718 and the high was 757 f.p.s., so a spread of 39 f.p.s. That’s large for a spring gun. At the average velocity Hobbys generated 14.32 foot-pounds at the muzzle. That’s on the low side of normal, but after seeing what Superdomes can do I think Hobbys may not be best for this rifle, either.

Firing behavior

This Diana shoots very smooth without much vibration. It’s certainly a lot better than a Diana 34 of 1990! I expect the Vortek kit I install to add some power and smoothness to an already smooth shooter.

Cocking effort

The Diana 34P cocks with 28 pounds of effort. The cocking cycle is smooth and does not build at any point. The trigger and safety both set without any extra effort.

Trigger pull

The two-stage T06 trigger breaks cleanly at 1 lb. 8 oz. That’s so perfect I just hope I don’t screw it up when I tune the rifle. Just kidding, George. Diana triggers are modular and don’t change unless you want them to.

I will have more to say about the trigger when I shoot George’s rifle for accuracy next week. That’s when I get the best evaluation of a trigger, because I’m concentrating on it so carefully.

Next

I will do the accuracy test next. That will be the heart of this report, because it gets to the root of Geroge’s complaint — namely variable accuracy. My plan is to start at 10 meters with 5-shot groups, to get a sense of the pellets the rifle likes and doesn’t like. Then I’ll back up to 25 yards and shoot some 10-shot groups. If I get what I consider a good group (10 shots under an inch at 25 yards with open sights), I will try to repeat it with the same pellet. It isn’t just accuracy I’m looking for — it’s repeatability. George, you correct me if I haven’t got it right.

No scope yet. After we know the accuracy potential I will either be faced with a problem — as in the rifle truly isn’t accurate — or I will know that it is accurate and can proceed to the tuneup. Won’t know which it is until we get there.

After the tune I will retest the velocity with these same pellets. Then, if the rifle is accurate, I plan to mount a scope and do one final accuracy test at 25 yards.

When this test is completed all readers will know several things.

1. How does a Diana 34P in .22 caliber perform?
2. Does the Rail Lock mainspring compressor work on Diana rifles?
3. What is the Vortek tuneup kit like, how does it install and how does it perform?

Evaluation

I am VERY impressed with the quality of George’s Diana 34P! It’s obvious to me that Diana has continued to make small improvements to this, their best-selling air rifle. When companies do that they are setting themselvs up for success!

26 thoughts on “Checking out a Diana RWS 34P: Part 2

  1. BB-
    I have 2 spring guns in my PA wishlist- this 34 P and the Walther Terrus. Looks like a pretty close race between these 2. I have a Diana RWS Model 5 pistol and I love the trigger on it. If you find this trigger to be better than what the Terrus has, it will probably tip me over to buy another Diana. I can’t shoot 0pen sights any more but I know of someone who developed a rail to solve a barrel droop issue for scopes!


    • BBB,

      The trigger on this particular Diana rifle is adjusted very fine. I love it. I would rate the Terrus as good as the average Diana trigger out of the box, but I think the Diana can be adjusted nicer than the Terrus. I’m not that good at adjusting triggers, though, so it’s pretty close.

      B.B.


  2. BBB-Do you shoot your RWS 5 with a scope? I LOVE my 6G!

    B.B.

    Seems, “So far so good”. Can not wait for the accuracy test. Curious to know where you will place your left hand? Also, would it be in a different place with a wood stock?

    Thanks,

    -Yogi



      • My 34-P with the synthetic stock seems to be less hold sensitive than most rifles. I tend to shoot it, as a lefty, with the web of my right (fore) hand at the cocking slot or even closer to the trigger. I support the forehand on a Predator thermoplastic shooting rifle rest, but do not rest the trigger hand (left) on anything. It is pretty much a point and shoot experience. It will be interesting to see how Mr. Gaylord fares with the 34-P.


    • Yogi-
      My model 5 was made a little before they had gone to putting scope rails on the pistol. It doesn’t have any way to mount a scope or dot sight, but I wish it did. I can’t shoot it any more so I probably should sell it to someone with better close vision. Also, mine was made before the “magnum” versions. It shoots 7.9 gr. at just over 400fps, if I remember correctly.


  3. B.B.,

    Just thinking that the performance seems to be increasing as the pellet weight increases.

    Velocity JSB Exact RS 13.43-grains with a spread of 25 f.p.s.
    RWS Hobby 11.9-grains with a spread of 39 f.p.s.
    RWS Superdome 14.5-grains with a spread of 16 f.p.s.

    Would a pellet like the JSB Match Diabolo Exact Jumbo Heavy .22 Cal 18.13 Grains perform as well?

    Siraniko


  4. Looking good so far. Can’t wait for the next part,… but I will 🙂 It will be nice to see the Vortek kit again and have it introduced to new shooters. I spoke with Vortek before I bought mine and they said that it does not really increase the fps much, if at all. The TX did see about a 30 fps. bump, but that was with a HO kit. The spring guides fit quite tight. The entire system is quite unique in it’s approach and is provided as a “drop in” kit/unit.

    Good Day all,… Chris


  5. BB,

    It is really quite interesting how the performance of a sproinger power plant can vary so dramatically depending on the weight, size and shape of the pellet. Many would think that the lighter pellets would be faster, but not necessarily so, as you have demonstrated.

    Also, the firing cycle itself can vary dramatically. My limited experience has taught me that most sproingers prefer a pellet within a certain weight range. Too light and the firing cycle is harsh and too heavy and the piston tends to bounce.

    It is nice to know that Diana is listening. In recent years they have been quite innovative and competitive with the higher end market, not just in price but also with quality. Their improvements to their flagship models as you say bodes well for them also. A Diana is very high on my short list.


  6. Darn, the Diana 24 is looking to be a real nice rifle… don’t have a .22 caliber springer… don’t “need” another springer so why do I find myself checking prices???

    Looking forward to the next blog on this rifle!

    Hank


  7. B.B.,

    Off subject, but I’ve long been waiting patiently for an Umarex Colt SAA 4 3/4 inch gunfighter model, but whoaaaa Nelly, a Shopkeeper/Storekeeper/Sheriff model? Oh boy! :^D

    Michael


  8. B.B.
    Things are looking pretty good so far…no surprises yet. I do not own a chronograph and I was surprised to see the JSB RS 13.43gr (rapid speed) pellet was much slower than the Superdome 14.5gr. I will say that I tried a sample of (25) JSB RS pellets at 25 yards and they landed all over the place. I determined right away that pellet was too light. You may find that the JSB pellets fit looser in the barrel which may be the cause of lower FPS? When I measured the JSB Exact 15.89gr pellets they were consistently .02mm smaller than any of the others I measured and .03mm smaller than the sticker indicated on the tin (5.52mm on the tin but 5.49mm actual).

    Are you planning on doing any specific barrel measurements, or just shooting it to see how the groups measure?
    Very much looking forward to next week’s accuracy test. This is where the rubber meets the road!


    • George,

      Measurements of the barrel don’t mean much in this case. It’s accuracy that tells the story.

      I do measure barrels when selecting lead bullets to shoot in black powder rifles and smoothbores, and I also measure them when loading certain firearms that are known to have barrels of varying dimensions — like SKS and Mosin Nagant rifles. But not pellet rifles barrels.

      B.B.


    • Geo,

      In reflecting back,.. I think of all of the times that I impatiently/anxiously awaited the next report on an item/topic that I was interested in. I am sure that whatever I ever felt,… it must pale in comparison to what you must be experiencing. 😉 Best wishes on a great outcome.


      • Chris
        I am just fine with B.B. taking as much time as wants to do this evaluation. I savor every step in the process, knowing that this is a rare chance for my rifle to be evaluated by a true airgun expert. So far what he has seen is all good. The fps was a little slow but otherwise the rifle is looking very good in his review. Next week will be the meat and potatoes of this review. I am anxious to see the outcome though…another cliff hanger.


        • Geo
          Yes in this case it’s the normal rigamarole. So nothing new yet.

          I want to see what happens when he gets down to shooting biusness.

          But did find it odd about the big lead in chamfer. I don’t like that. In a spring gun I like to feel the pellet engage in the rifling of the barrel. Once you get a feel of how good shooting pellets load. You can pretty well tell how your shot will go from previous shooting exsperiances with that gun.

          You know like checking your parts with your micrometer at work.


  9. Kind of different on the big lead in chamfer on the breech end of the barrel.

    Wonder if all the current models are like that.

    Or maybe this one gun is like that. Interesting though.



    • Cobalt
      I myself don’t like the lead in chamfer on this gun. Like you say. No smooth transition at all.

      Looks more like it would cut or shear the pellet head when loading.



    • Cobalt
      Yep that’s what I’m talking about.

      But still we should wait and see what BB’s shooting results will be like.

      I’m can’t say one way or the other. But it will be interesting to see how BB explains what happened with his results.

      But again. Like the arrows you displayed. To me that’s a problem area.


  10. Hi all,

    I did quite some relieving of diana breeches. It actually does not seem to matter so much to take off more on the top. Maybe it saves a little dead air. I found just grinding by hand with some rubbing compound you can make a small smooth recess and the pellets all get centered by their heads. The emphasis is on little is more on this though. I have done this with many diana 27’s and they all performed as wonderfully afterwards as before.

    Also, as a vortek fanboy I can not say enough good things about the kits they make. You have not lived a full life until you have shot a well adjusted vorteked HW30S.

    I sold my vortek kitted HW30S in a fit of madness.. After I got my 50S. Darn I miss that rifle, and I feel so silly about it too.

    Carel


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