Diana 35: Part 5

by Tom Gaylord
Writing as B.B. Pelletier

Diana 35
Diana 35 pellet rifle.

Part 1
Part 2
Part 3
Part 4

A history of airguns

This report covers:

  • Basic velocity test background
  • Today with Hobbys
  • Firing behavior
  • Cocking effort
  • Trigger pull
  • Qiang Yuan Training pellets
  • Falcons
  • Discussion
  • Summary

Today we see how the lube tune and cleaning I did with the Diana 35 affected velocity. In addition to what I told you in Part four, I also put 5 drops of Crosman Pellgunoil down the transfer port five days before this test, to soak into the leather piston seal.

Basic velocity test background

We don’t know a lot about this Diana 35 powerplant, apart from the work I showed you in Part 4. I did test it for velocity in Part 2 with RWS Hobby pellets, but that was all I did. I knew I would be going into the powerplant anyhow, so all I wanted was to establish where the rifle was when I started.

You may recall that I replaced the breech seal and the metal shim underneath it before ever shooting the rifle. That seal was shot and I didn’t want to damage the rifle by what might have amounted to a dry-fire, so I held off until the new seal and shim were in place.

Hobbys averaged 603 f.p.s. after the breech seal was replaced. The spread ranged from 587 to 618, for a total of 31 f.p.s. I thought that spread was on the high side.

Today with Hobbys

Let’s look at how the rifle did today. I’m going to show you the first 20 shots and then I’ll discuss them.

Shot………..Vel.
1……………614
2……………631
3……………672
4……………695
5……………492
6……………522
7……………571
8……………525
9……………639
10…………..658
11…………..626
12…………..616
13…………..631
14…………..604
15…………..609
16…………..613
17…………..592
18…………..602
19…………..600
20…………..603

The “average” for that string is 606 f.p.s. The spread is 203 f.p.s. (492 to 695 f.p.s.). The oil in the piston seal needed time (shots) to distribute itself and for the excess to be pushed out of the compression chamber.

I didn’t know how many shots I had fired until after I finished and counted them. I didn’t stop at 20 shots for any particular reason. I stopped because it looked like the rifle was starting to settle down. Now, let’s look at the next 10 shots.

Shot………..Vel.
1……………605
2……………594
3……………607
4……………614
5……………583
6……………598
7……………613
8……………598
9……………606
10…………..588

Yes, the rifle is settling down. The average for this string is 601 f.p.s. and the spread goes from 588 to 614. That’s 26 f.p.s. In other words, the velocity and consistency of this rifle hasn’t changed very much after lubricating it. I thought the Tune in a Tube grease would slow things down a bit, but apparently it didn’t.

Firing behavior

The rifle now shoots very smooth. There is some forward recoil, but very little in the way of vibration — just a solid “thunk!” It’s not as smooth as Michael’s Winchester 427, but for the additional power it’s very smooth.

Cocking effort

Before the lube the rifle cocked with 18 lbs. of effort. Knowing Diana 35s, I knew that was light. It should have been between 28 and 30 lbs.

After the lube the rifle cocks with 16 lbs. of effort. The drop is due to all the lube, but I think the most important parts affecting the cocking effort were the base block washers on either side of the barrel pivot and the pivot bolt itself. The rifle is now absolutely silent when it cocks.

Trigger pull

Before the lube the second stage of the trigger broke at 3 lbs. 10 oz. After the lube it still breaks at 3 lbs. 10 oz. Stage one is 2 lbs. 9 oz., which is due to the heavy trigger return spring I mentioned in Part 4. I thought lubricating the dry ball bearing cages and the balls themselves would have some effect on the pull, but as you can see it didn’t. Perhaps that speaks to the genius of the ball bearing trigger design?

Okay, let’s look at a couple more pellet velocities. Prepare for a surprise!

Qiang Yuan Training pellets

The second pellet I tested was the 8.2-grain Qiang Yuan Training pellet. These wadcutters have often been surprisingly accurate, though I have never tried them in this rifle. They are significantly heavier than the 7-grain Hobbys, so I expected a drop in velocity. Surprise! This pellet averaged 626 f.p.s. for 10 shots and the spread was only 14 f.p.s. (620 to 634 f.p.s.). At the average velocity Qiang Yuan pellets produced 7.14 foot-pounds of energy at the muzzle. This is definitely a more efficient pellet in this rifle!

Falcons

After the accuracy test I did in Part 3 I had to test Air Arms Falcon pellets, too. They are so darned accurate in this rifle! Ten Falcons averaged 637 f.p.s. in the 35 and the spread was just 12 f.p.s. (631 to 643 f.p.s.). At the average velocity the 7.33-grain Falcon produces 6.61 foot-pounds of muzzle energy.

Discussion

Tune in a Tube did not reduce the velocity of the 35 at all. But it did make it smoother to shoot. The forward recoil keeps this rifle from being as smooth as Michael’s Diana 27/Winchester 427, but it’s far smoother than my Diana 27/Hy Score 807 that I recently goofed up with a Krytox lube-tune. I’ll have to get back inside that one and tune it right some day, but as nice as this 35 is, that day may take some time to arrive.

Summary

Well, the 35 is up and running and ready for some accuracy tests. Since the rifle has no base for the Diana peep sight I can’t try it with that or with a scope, but that’s okay. I like this old girl just the way she is, and I can still shoot with open sights. That test is coming next!

35 thoughts on “Diana 35: Part 5


  1. Hey all,

    The Longest Day (in the Northern Hemisphere) is upon us!
    For those blog readers in the Southern Hemisphere enjoy the extra hours of darkness for some restful sleep.

    At some point this weekend check out this link to see some sobering information about a group not very friendly to our sport:

    https://lawcenter.giffords.org/gun-laws/policy-areas/child-consumer-safety/non-powder-toy-guns/

    Check out the sections on the tactics and policy approach these folks are spreading to bring an end to any kind of shooting sport heritage. Also if you live in the USA see how accurate you and they are in current rules/laws on non-powder guns in your state.

    shootski


    • Shootski,

      It is obvious that laws and regulations have done little to prevent gun violence. We have a violent culture and tend to use violence to settle our conflicts, disagreements and differences. Until we have a more benevolent culture there will be violence and increasing laws and regulations that take away our freedom.

      Much of what the Giffords are trying to do can be done much better with gun safety training in my opinion.

      Don


    • “Between 2001 and 2011, non-powder guns injured 209,981 people nationwide”

      Shootski,
      I can counter that with:
      “Between 2001 and 2011, automobiles caused 435,182 DEATHS, nationwide.” (not counting injuries!)
      (https://en.wikipedia.org/wiki/Motor_vehicle_fatality_rate_in_U.S._by_year )
      “In 2012 [alone], an estimated 2.36 million people were injured in motor vehicle traffic crashes, compared to 2.22 million in 2011 according to NHTSA’s National Automotive Sampling System (NASS).”
      (https://crashstats.nhtsa.dot.gov/Api/Public/ViewPublication/811856)
      That is much MUCH worse, but I don’t see them trying to ban cars.
      I don’t think these people care about statistics except as a tool to try to further their anti-gun agenda because they just plain don’t like guns. Fine; then they shouldn’t buy any; but please leave ours alone.
      I wish the whole kit and caboodle of them would move to say, North Korea; after a few years of living under a Communist dictatorship, perhaps they would have more of an appreciation for the rights of others instead of trying to take them away.
      Thanks for letting us know about these folk; we can’t keep an eye on them till we are aware they exist. =>
      Take care,
      dave


      • Thedavemyster,

        One thing you failed to mention is all the deaths and injuries directly caused by the use of cellphones while driving. I would love to see the statistics on that! I would not be surprised if they exceeded airgun and firearm deaths combined, disregarding of course LEGITIMATE self defense shootings and suicides.

        Can you imagine the public outcry if they (cellphones) were banned? How about treating them like transporting a firearm in some states whereby they must be locked in a case with the battery removed and not stored in the passenger compartment of the vehicle. I could live with that and so would a lot of other people, literally!

        There is no cure for stupidity but it is truly sad that so many innocents are killed by the irresponsible behavior of idiots, whether it be vehicles, guns or cellphones.

        Bugbuster


        • Bugbuster,

          Amen…and amen. Ignorance can be corrected with education, but stupid is forever!

          Last year a lady down town was looking at her cell phone while walking across the street. She unknowingly walked right into the rear duels of a semi-trailer and was killed. I have heard it said that texting while driving is now causing more accidents than drunk drivers. A close friend was almost hit by a lady in a pickup recently. She was making a right turn on red and Roger was walking in the crosswalk. She was on her phone while turning. He had to push off on her hood to keep from getting hit. He’s 82! She gave him a dirty look and continued on her way. It really shook him up and now he won’t use the crosswalk anymore. We cross the street in the middle of the block now.

          Geo


        • Buggy,

          I will second Geo,….AMEN! While not much better, there is hands free use now that is very common. Mine is off limits while driving. I still see WAY too much of it though.

          I will say that I do see more people pulled off in odd places and using a cell. Good for them.

          Chris


        • Bugbuster,
          You nailed it! That is my wife’s pet peeve! (I can’t believe I forgot to mention that).
          Georgia went “hands free” a few months ago, but that has had little effect.
          A few weeks ago, my wife was several car lengths behind two other cars that went through a green light. My wife had some kind of premonition to slow down (the light was still green for her), and just then, some jackwagon of a woman with a cell phone pasted to her ear ran the light, and would have killed my wife had she not slowed down!
          The only thing my wife could figure is someone else going the same way as that lady made a right turn on red. My wife figures the lady saw that in her peripheral vision, felt the light must be green (no need to interrupt her phone call by actually looking up! #_#), and plowed on through, phone pasted to her face…yes, sheer idiocy.
          Thanks for reminding me about that! I’ll let my wife know she “made the blog.” =>
          take care,
          dave


  2. BB,

    This old gal is turning into quite a sweetie, eh? None of the more mature ladies residing at RidgeRunner’s Home For Wayward Airguns will accept a scope. That is part of their charm for me. They take me back to my youth and learning the basics of shooting. It is one thing to hit a 3/4″ spinner at 10 yards, but you have to get things right to hit that same spinner at 25 yards.


  3. BB

    There is much to like about this Diana. The 16 pound cocking effort generating 600+ feet per second velocity is my favorite feature. It requires nearly half the effort compared to original specifications if your information on it are correct. Would you or Carel or anyone care to explain how this can be?

    Have a good weekend everyone!

    Deck


    • Deck,

      I have long suspected that the piston stroke is responsible for most of the power in a spring gun. If I were to upgrade the mainspring in this rifle to a new one I think the pellets that now go 630 f.p.s. would go 700-750 f.p.s.

      You know, I might be talked into doing that just so we would all know.

      B.B.




      • B.B.,

        An interesting hypotheses!
        It would seem a mainspring change wouldn’t change the stroke – would it?
        Not being much of a Springer guy I should think an old gun with a spring tube, cocking lever and a barrel mounted in a fixture could become a stroke length testbed. It might already have been done?
        Anyone know of that kind of testing?
        If my Ottocycle knowledge has any bearing on this then a long stroke provides more power per stroke cycle than the same swept volume change by increasing the bore diameter. I vaguely remember it has something to go with the actual Mass of the piston.

        shootski


        • Shootski,

          Correct. An under powered spring can be improved (more fps) by a heavier spring and an over powered one can be shorter/weaker and you may not loose any fps, but will most likely smooth things out a bit more. Neither affect swept volume/piston movement/air displacement. Since the latch rod (part of the piston),.. must end up at the sear when cocked,…. and the piston must come to the end of it’s stroke for maximum compression, when released,… the stroke is fixed.

          As I recall, like you, the longer stroke approach is better.

          Chris



            • Dave and Chris,
              The complete Otto Cycle doesn’t really apply to the Springer as you to know. The two stroke cycle might actually be closer; especially with a Springer that Diesels. The losses to friction and inertia was what I was pondering about.

              I try to learn something new everyday; most of my 70+ years f dass I have done it! With lots of help along the way :^)

              shootski


  4. In our race to embrace modernity with airguns like the FX Dreamline, amazing features and functionality, guns like this Diana remind me of the virtue of reliability, something that can easily get lost in my cluttered gun closet!
    My P1 and R10 are the working backbone of my tiny collection. They always work, even with broken springs.
    The Diana Bandit got a regulator and some valve work, nice groups now. Why it doesnt come from the factory that way I’ll never know. Save your money and get decent guns, choose wisely! Thanks for all you do Mr B.B.!
    Now back to your regularly scheduled show.
    Rob


    • Rob,

      Although my next purchase in the airgun department will be a FX Dreamlite, most of my meager collection is airguns that are older than I am. Most of these old gals were built with a quality that is rarely seen in these modern times. It is such a joy to spend the afternoon shooting my BSA that was built in 1906. Will that Bandit still be up to it 113 years from now?


      • RR,

        “Although my next purchase in the airgun department will be a FX Dreamlite,”………..

        Sounds like you have it nailed down solid. Best wishes on getting it done and end up thrilled in the end.

        Chris


        • Chris,

          I am certain I will be thrilled with it. A Man From U.N.C.L.E. air rifle that is of quality construction, versatile and accurate. I can shoot field target with it one day and hunt medium game with it the next.

          The only issue with it is that my HM1000X will likely have to find a new home. I can’t afford to board both of them at RidgeRunner’s Home For Wayward Airguns.


    • Rob,

      I may be imagining things, but I swear I can hear your R10 calling to you to take her outside this morning. Maybe it is just my BSA calling to me. These old ears can play tricks on me.


  5. B.B.,

    I know you dislike making comparisons but because of your latest numbers it’s hard not to ignore that this is R7/HW30 territory.

    Considering that power is so similar, which do you prefer shooting, the Diana 35 or an R7/HW30?

    kevin


    • Kevin,

      I never thought about it until you mentioned it, but you’re right.

      The R7 probably has the better trigger but I like the size and shape of this Diana 35 better. This particular rifle seems to shoot the best of any I have tried in .177. But I guess if I spent the time with an R7 I’d find a good pellet for it.

      Given that the R7 is still being made — what a wonderful thing!

      I like what I have, but if I didn’t have it, an R7 would work! Or an R8.

      B.B.


  6. B.B.,

    16 pounds of cocking effort sounds pretty nice to me, especially as my shoulders are becoming a little arthritic. It might not be as smooth as my Winchester 427 / Diana 27 you tuned to perfection, but it still seems pretty sweet nonetheless.

    Incidentally, I tried my Morton H. Harris Marksman this morning, and it came back to life entirely, shooting a strong (for one of those, of course) 200 fps. I don’t know what happened, but I’m happy it did!

    Michael


  7. B.B.,

    Off topic, but a crazy idea popped into my head. What if you wrapped the shot tube of your Pioneer ’76 BB gun in a soft, thick fabric, such as a velvet or felt, and then ran a neodymium magnet along it? It probably will accomplish nothing, but who knows, perhaps that stuck BB will come loose. Take care, of course, to make sure the magnet doesn’t mess up the loading spring or any other moving parts.

    I thought of that this morning as I went online to buy a few dozen neodymium magnets before the U.S. price for rare earth magnets goes up because of the tariffs on Chinese imports.

    Michael




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