Diana 340 N-TEC Classic air rifle: Part 2

by Tom Gaylord
Writing as B.B. Pelletier

Diana N-TEC 340 Classic
Diana 340 N-TEC Classic air rifle

Part 1

This report covers:

  • Cocking effort
  • RWS Hobby pellets
  • H&N Baracuda Match pellets, 4.50mm head
  • RWS Superdome pellets
  • Why the slow shots?
  • Trigger
  • Evaluation so far

Cocking effort

Today, we’ll look at the velocity of the Diana 340 N-TEC Classic air rifle. I said in part 1 that cocking this rifle is a chore for 2 hands, but I’ve learned something about the gun in this test. The gas spring isn’t the only thing I’m fighting to cock the rifle. The barrel pivot joint is also a bit too tight. The cocking effort is about 35 lbs, which isn’t that bad, but the pivot joint boosts that up to 42 lbs. It made the rifle difficult to measure, but I soon learned to rapidly pull down the barrel and bypass the pivot joint tension. Then, it is a one-handed operation.

RWS Hobby pellets

Let’s get right into the velocity testing. We’ll begin with RWS Hobby pellets. The first shot out of the rifle went through the chronograph at 1070 f.p.s. I mention that because some airguns need a shot or 2 to “wake up” the powerplant. Not the 340 N-TEC. It averaged 1084 f.p.s. with Hobbys, and the spread went from 1069 to 1121 f.p.s. That’s 52 f.p.s. — a little high for a spring gun.

At the average velocity, Hobbys produced 18.27 foot-pounds of energy at the muzzle. That’s a lot for a .177 and too much for this lightweight pellet when long-range accuracy is concerned.

H&N Baracuda Match pellets, 4.50mm head

Next up was the H&N Baracuda Match pellet with the 4.50mm head. This may not be the most accurate pellet because of the head size, but it should give a close approximation of all similar pellets of any head size. This domed pellet averaged 835 f.p.s. for a 10-shot string, but there was an anomalous shot that went only 686 f.p.s. Throw out that one shot, and the next slowest shot went 818 f.p.s. The high was 869 f.p.s. At the average velocity (835 f.p.s.) this pellet produced 16.49 foot-pounds of energy. The spread for 10 shots was 183 f.p.s.

If I average the 9 fastest shots the average climbs to 852 f.p.s. At that speed, the energy jumps to 17.17 foot-pounds. The spread for the top 9 shots was 51 f.p.s. I think that’s more representative of what the rifle can do.

RWS Superdome pellets

The last pellet I tested was the 8.3-grain RWS Superdome. I’d tested a light pellet (Hobby) and a heavy pellet (Baracuda Match), so the Superdome represents a medium-weight pellet.

The 10-shot string also had one anomalous shot at 811 f.p.s., but the other 9 ranged from 922 to 960 f.p.s. For the 10 shots the average was 924 f.p.s., with a muzzle energy of 15.74 foot-pounds. But the 9 fastest shots averaged 937 f.p.s., for an energy of 16.19 foot-pounds, which I think is more representative. The spread for 10 shots was 149 f.p.s., but the spread for 9 shots was 38 f.p.s.

Why the slow shots?

If you recall, I had some slow shots last month when I tested the Diana 45 (see Part 8). I thought that had to do with the start screen of the chronograph triggering too soon from the muzzle blast, but this time I held the muzzle back from the start screen about 12 inches. I don’t think it was that, though I still need to do more testing.

Trigger

I didn’t like the trigger during this test. It feels like a single stage that goes off whenever it’s ready. It is entirely unpredictable as it came from the box. The manual says stage 1 is reduced to the minimum at the factory — so that had to be corrected.

I adjusted stage one to be longer — hoping that stage two would become more positive. That didn’t happen.

Then, I adjusted what the manual calls the pull-off. I was hoping this would make stage two more positive, and it did just a little — but not as much as I’d hoped.

I finally adjusted the trigger-pull weight to the maximum, which is 500 grams. I’d hoped this would make the trigger crisper. It did clarify a little where stage two is, but the let-off is still very vague. This will be a trigger the shooter must learn, rather than one that can be set to break crisply.

It isn’t a heavy trigger, nor does it have any creep. It’s just vague. But the way I have it adjusted now, I’m sure it’s good enough for some target work.

The trigger now breaks at 1 lb., 11 oz. It’s positive enough that I’ll be able to shoot to the rifle’s maximum capability. But make no mistake, this isn’t a T06 trigger. It may be an adaptation, but it isn’t as positive as the T06 or T05.

Evaluation so far

Trigger aside, I really like the 340 N-TEC. It is, perhaps, better in .22, but it’s a powerhouse in .177. If the rifle is accurate, I think it’ll become a best buy — even considering the price. We shall see!

63 thoughts on “Diana 340 N-TEC Classic air rifle: Part 2


    • Out -of-the-box, the gas ram version of the T-06 (It is in fact a T06, if you believe Diana. I do.) performs as described above. The 1st stage adjustment screw must be replaced with a longer one. Once that’s done, you can set up a trigger with a firm back wall and a crisp 2nd stage relaease, as good as any out there.

      The ram on this test unit sounds hot. Mine delivers about 14-15 fpe (8.47 grain AA diablos (JSBs) running 876fps. CPLs run about 916 fps, for 14.8fpe), which is a more reasonable power level for .177.

      The barrel pivot on mine was tight as well — I expect the factory wants this hinge point to ‘wear- -in’. I just loosened the pivot, a 5 minute job.


      • Hey guys! Lost (kids did a magic trick) my phone for the last two weeks and just got it replaced, but wanted to second the t06 gets right a defined with a screw about 1/16th longer. Two different t06 copies have so far been saved with this trick. Without it they were basically floppy.


  1. B.B.,

    Nice description of your efforts to adjust the trigger, (did X ,..got,.. X results). While I suppose not a must, it would seem that anyone adjusting triggers much at all, would find a trigger gauge usefull, (measurable data). Noteing adjustments along the way seems like a good idea as well,..in case you want to return to factory settings.

    “Anomalous” shots got my interest as well. Looking forward to your review of your new chrony.
    While I did not experience extreme lows, I did see some Err1 or Err2, despite everything being done the same, or at least,.. it seemed the same. { Any idea on about when you may do the report? }

    Thanks, Chris


  2. BB,

    Quite frankly, I am surprised by your evaluation so far. You are telling us that you are getting huge velocity spreads and the trigger is vague. With such characteristics and a price tag that puts it up there with some truly fine sproingers, I would say this is a no go, not a best buy. The accuracy will have to be incredible for this to be worth the selling price.

    I think you are just enamored with the fact that it is a magnum gas sproinger that you can cock and it is not slapping you side the head, or did it slap you real hard and addle your brain?


    • RidgeRunner,

      I think I’m gonna have to agree with you that unless the accuracy with this rifle is fantastic it’s a non-starter. Definitely not a best buy.

      B.B. does talk sometimes about guns redeeming themselves at the 11th hour in the accuracy phase so let’s see what happens there before making final judgment.

      G&G


    • With velocity spread that wide I doubt that the gun is accurate. Think about it, if you shot drops over 100 fps from the last shot, your shot will land significantly low on the target. Does NOT matter if you have the MOST accurate barrel in the world.



  3. I dunno, I think I’d just spend a little more and go with a Walther LGV. I know mine was pretty much perfect right out of the box, with no tweaking needed. And, I sure can’t see this gas ram replacing my Diana 34.


  4. B.B.,

    Are you using a Shooting Chrony? I believe the manufacturer recommends a minimum distance of 3 feet between muzzle and first screen for an airgun or .22 rimfire (http://www.shootingchrony.com/english_QS_BG.htm). That might account for some of your erratic velocity readings, and I would expect the effect to be more pronounced for a magnum than for a less powerful airgun. Though there are plenty of YouTube videoes showing folk testing their airguns at much closer ranges!



    • But you are talking about a firearm, a rimfire; an airgun has no muzzle blast, so you can be 6″ away if you want and that would be MORE accurate when measuring the muzzle velocity.


      • Joe,

        The setup guide I linked to specifically lists airguns:

        “Distance of Chrony unit from muzzle: Air gun, .22 Rim fire => 3FT”

        I have to assume the manufacturer has a reason for that. And I think an airgun does have a muzzle blast; it’s just composed of air or CO2 rather than ignition byproducts. I can actually see gas exiting the barrel in airgun video I’ve shot.



        • BB,
          You are right about the blast. I always thought a chrony measures an object passing through its two sensors, an object such as a bullet/pellet and not a blast of air or co2, correct?

          I never had any problem using a chrony to measure velocity of my airguns which are always 6 to 8 inches away from the chrony.

          I DO BELIEVE that the hot ignited gas from a firearm do confuse up the chrony’s sensor, this firearm need to be further away from the chrony.


          • The sensors detect changes in light level — normally of objects passing over them, but changes in air density can cause refraction of the light, and such “ripples” can be sensed as an object.


  5. Edith,

    Tried to post a comment and it did not show up; may have been because I included a URL. Tried again and was told it was a duplicate post, so I’m assuming it’s floating around in cyberspace awaiting approval. Thank you.


  6. B.B.

    RidgRunner has a point….Overly powerful power plant, vague trigger… Sounds like everything you hate about gas rams! If you think .22 would be better, would .25 be even better? When I go plinking, or “Beer Bottle Destruction Derby”, as my friends call it; I like having 8oo fps behind me. It makes the 60-75 yard shots almost as easy as the 40 yard ones. Less than 800 fps and the pellet drop would have to be a major consideration at the longer distances.
    Which gas ram springer has the best trigger?

    Thanks,
    Yogi


    • Yogi,

      I do not know what BB may say to your query and I have not tried one myself, but I have been hearing some good reports about the Hatsan 95. If you can afford it and are in pretty good shape, the Beeman RX2 / HW90 might be a good one. Both of these have gas springs that can be adjusted also.


      • The hatsan trigger is very nice, as soon as I get it going again I’ll tell better, heres the lesson in power craving… its still down from buying the wrong spring! Round peg in a square hole… springs are not a horseshoe and handgrenade part! The low power springer stuff I just missed has been the plan for it since that whole debacle last fall. I pretty much just now pulled the guns out for some plinking after a long winter and horribly drawn out move.



  7. RR
    I have a new Hatsan 95 Vortex in .22. Other than a heavy trigger pull, but VERY linear, it is wonderful. 200 pellets since its initial cleaning and it still diesels sometimes? If anybody knows, please let me know, does the Hatsan quattro trigger need a 3 and a 4 mm allen wrench for adjustment?
    thanks,

    Yogi



  8. BB,
    You said ” H&N Baracuda Match pellet with the 4.50mm head. This may not be the most accurate pellet because of the head size…”
    Could you please elaborate on it? I’m not clear as to what you said.


    • Joe,

      We have been testing the same pellets with different head sizes over the past few months and we have seen that the head size sometimes makes a big difference, as far as accuracy goes. The Baracuda Match pellet has 4 head sizes to choose from.

      I meant that the 4.50 mm head pellet might not be the most accurate one, but that would make no difference as far as velocity is concerned. So maybe I test the 4.50 mm head pellet for velocity but later I discover the 4.53 mm head is the most accurate.

      I am saying the 4.53 mm head would probably have similar velocity to the 4.50mm head. So it makes no difference which head size I test when I am testing velocity.

      B.B.


  9. BB–I just watched the video re the Parker Concorde self cocking crossbow. There is no information re the cold weather performance of the co2 powered system. Do you think that it would work in below 0 temperatures? I did not find any information re the weight of the Concorde. It reminds me of the many combination weapons of the past that sound good, but prove to be too heavy and complicated to be practical in the field. The flying tank and the pistol-sword are some examples. Ed


  10. B.B., Thanks for the blog ! Very interesting. I notice in the new Shotgun News your report on the SHOT show you mentioned many new air guns. I would be most interested in a Walther Terrus air rifle blog.
    Pete Hallock
    Orcutt, California


  11. I still fail to see the advantage in gas rams…..can be left cocked indefinitely….why would anyone do that?, pointless and possibly dangerous, this is the Weihrauch HW90 all over again, take a very good mid range spring gun, make it harder to cock and ruin the trigger
    I’ve got rifles that haven’t seen a new spring for 20 years, nor do they need one so longevity isn’t the answer….puzzles me….like someone has decided the only bit that really does work well and reliably needs changing because it’s old tech
    Stand by for square bicycle wheels, or someone selling us water in bottles
    Oh…hang on, the second one might have happened


    • “…why would anyone do that?”
      —Hunters stalking quarry will often want to leave the gun in a ‘ready’ (cocked) condition. That’s why.

      Unlike springs, rams:
      –do not torque the gun to the side.
      –don’t produce noise or ‘twang’ on cocking or firing
      –require very little lube. Lube impacts performance consistency due to temperature-induced changes in viscosity.

      Those are the advantages, real or imagined.

      Nothing wrong with metal coils, if that’s your preference..


      • SteveInMN,

        I myself have to agree with most of your reasons many give for going to gas sproings. As for leaving it cocked for hours, it does not hurt a good quality spring. It might not be a good idea to leave it cocked for weeks or months, but that is not a good idea anyway.

        The real underlying reason for going to a gas sproing though is the exact same reason everybody buys the latest iJunk, it is the latest.

        I still use a flip phone and the only reason that I have one of those is so my wife can get in touch with me when she wants to, otherwise I would not have it.


      • SteveinMN,
        I agree.
        Being a Hunter I would like to take my airguns in the woods on an all day hunt without worrying about the spring.
        I own a TX200 MKIII and would love to take it on long hunts so I emailed Air Arms asking about leaving it cocked all day while on hunts.. Their reply was, and I quote.. “The technical department have advised that it is not a good practice to leave it cocked, but tests show no damage when left for a few hours.” unquote.
        So I guess that means don’t do it, But it wont hurt it. LOL.

        I don’t understand why so many people are afraid of change or something new. I think Springers are great. But I also think when the manufacturers get the bugs worked out of gas springs they will be great also.

        Getting rid of the “twang” and spring torque alone is worth trying something new.
        “Springers” aren’t perfect either, Or there would be no spring torque or “twang” or spring fatigue.

        I’m glad it’s B.B. doing this review. Sounds like a lot of others are too bias to give an honest review.

        Thanks B.B. for all your great work!



  12. Innovation is only a necessity for engineers to keep their jobs as in the age old saying and one I try to live by is
    “If it aint broke don’t fix it ” There is no reason to change or reengineer anything unless it actually improves the product and so by BBs report I have not seen where the gas spring has improved the gun in anyway at this point.

    It just like all the newbie tech crap on new cars as it has not improved the car in anyway other than increase the price tag of the vehicles and add more distraction for driver to take their concentration from the road and place it adjusting or fiddling with some gadget in the car.

    I owned a 1964 Pontiac GTO that would get 22 to 23 mpg on the highway at 80 mph and a solid 18 mph around town and had no creature comforts except am AM radio and a heater, but was capable of running the quarter mile in 12.70 seconds off the showroom floor and only cost under 3000 dollars. it had a 389 tri-power carb setup with a four speed and a posi rear end with only an alternator on the engine and no AC, Power steering, or disc brakes but only a single cylinder master cylinder and four wheel drum brakes It weighed 2875 pounds according to the state of Florida vehicle registration as they charge by the vehicles impact on the road due to weight. It had no seat belts and was one of most fun cars I ever owned since the only distraction there was in the car to take your attention off the road was the fact that it could light the tires up at 60 or 70 mph at will which actually made you pay more attention not less since it would try to go around in circles due to the posi rear end and natural torque of the motor causing the vehicle to rotate around itself.

    We need simple in our lives not more complex.

    BD


    • Your $3,000 in ’64 equals $22,715 today — and the cars are (much) more efficient, equipped and comfortable.
      No argument with the ‘simplification bias’; that’s a preference thing. But inflation is what it is, and $22,715 is a LOT for a car with nothing but AM and heat, isn’t it?


      • SteveinMN
        From your comment you have obliviously never drove a 64 tri power goat or any other 60s or 70s muscle car or you would understand my opinions.

        As far as inflation and the under 3000 dollar goat costing 22,715 now . you tell me what 22,715 dollar car you can buy today that makes well in excess of 400 horsepower, can turn a 12,70 quarter mile all day long and run 80 mph on the highway and get 23 mpg and as far as inflation is concerned you have totally forgot that the 64 goat is touted as the car that started the muscle car craze of the 60s and 70s and was the first car to outrun the fuel injected corvette in a quarter mile for showroom stock.

        So as far as inflation goes that under 3000 dollar car is now worth in excess of 150,000 dollars in today market if you can find one as there were 6500 64 GTOs built but only 650 64 GTOs built that were delete A/C, Power steering, power brakes and front disc brakes, AM radio only and no soundproofing or mastic, 4 speed close ratio M22 rock crusher Muncie trans and 3.30 ratio posi rear end so that exact car today is worth way in excess of 22,715 dollars if you can find that exact model.

        Now take any car you can buy today for 22,715 and keep it in new condition for 51 years and see what you can sell it for then as I would wager to say you would be lucky to get a loaf of bread or a galloon of milk for it.

        But that is why we still have the freedom of choice and the right to our opinions for now any way as I believe it is going to also be a thing of the past within the next two years as I will be very surprised if there is a 2016 election. If Hillary get the office you can most certainly say good bye to any freedom you have today as sure as it rains every day somewhere.

        BD


  13. B.B., off subject, on the 2015 Shot Show Day 1 Report, you showed a pic of a Gamo single stroke pneumatic, with a couple other Gamo pumpers. Have you heard anything else about the single pump? I’ve tried finding something on the web about it, but have came up with nothing. Thank You, Bradly


  14. I’ll be interested to see the accuracy of this rifle, but large velocity variation will definitely affect it.

    Mike, you are correct about tactical lights as I found from no less an authority than Larry Vickers, the ex-Delta Force operator and now teacher. He has all sorts of interesting info on his website. With respect to white light, he says to use it as little as possible and always move to keep from being a target. But this is for combat, and he does not speak to other uses like hunting or plinking in the dark where nobody will be shooting back at you.

    Vickers also speaks to combat accuracy. For various reasons, he says that 5 MOA is all you need for a combat situation and anything else is superfluous. He also says that in combat, you will only shoot to 50% of the gun’s capability, and that is with Delta Force type people. Others will shoot a lot less. That is an interesting concrete figure on the subject of being as accurate as the gun. He goes on. If 5 MOA is the max effective accuracy, it means that your gun only needs to be capable of 2.5 MOA which he confirms with 10 shot groups. If I recall from our discussion years ago, a five shot group will be, on average, something like 70% of the size of a 10 shot group other things being equal. So, this works out to a gun that groups just inside of 2 MOA for five rounds as your theoretical maximum for a combat weapon. That doesn’t apply to Designated Marksman Rifles and up. These are interesting specifics on long-standing questions, and you won’t find many people more qualified than a Delta Force operator to talk about this.

    Vickers seems like a pretty cool guy, and it would be something to take one of his classes. On his site, he says that some people, generally with a military background, will criticize him and his methods in the class. That would take some nerve I would think…

    Matt61


    • It fits. That puts the old AK right on the mark it being a 4 or 5 MOA rifle. Still, I normally like something with a bit more accuracy. Like my M-1 which is about 2 MOA with military ammo. But, when it’s -20F and snowing side ways here in the UP of Michigan, I would reach for my AK if it were ever needed.

      Mike


  15. To All,
    I have an opportunity to purchase a .22 caliber break barrel rifle. Is the powerplant pf the Diana Model 34 suitable for +18 grain pellets? Most of the tests here I have read are in .177. What are your experiences in using this in .22?
    Thanks in advance for your opinions


  16. You can quite happily leave a springer cocked for hours at a time…..if you’re hunting somewhere you need to leave it cocked all day, I would suggest you may not be in the right spot
    Until someone can show me a distinct advantage, (though I don’t have an issue with the tech provided the rifle otherwise shoots well), I wouldn’t bother looking for a gas spring rifle for that specific feature
    It doesn’t improve accuracy, nor handling, more often than not is both harder to cock and harsher to fire, the triggers seem to be slightly worse than the spring gun donors
    If it does last longer, and you have to talk in terms of decades here, it’s going to be more expensive to replace, offsetting any advantage.
    Nope, this “next big thing” currently at any rate, evaporates under critical reasoning.
    This one seems very fast, much faster than factory claims or other customer experience, it’s a testament to the 34 design it’s coping ok.
    Are these recent Chrono anomolies down to unfamiliarity with equipment then?…..because 50fps variance is going to really show on target……I smelt a little rat when the Diana 45 would sporadically drop it’s velocity in half but miraculously do half inch groups at the same time….
    The advantages for rams as pointed out by SteveinMN, really are rather more imagined, or at least technically correct….but in reality the gas spring is not affecting World FT rankings, despite their poor old TX’s and Diana 52’s twisting from their grip upon firing :-)…….so brings nothing to the accuracy table.
    We can’t even call this new tech either….when did Theoben start this?……..been an awful long time ironing out the bugs.



  17. My chrony which is the same model and new since December does this exact same thing. I use it indoors in a darkened basement with small floods above each skyscreen. I just throw out the anomaly. When I have a 50 fps spread it’s time to restart.


    • My alpha chrony master started doing the same thing and the low battery light had not come on yet but I put a new 9 volt in it and have had no issue since and that was 6 months ago and it was only 3 month old when it started.

      They come with very cheap 9 volt battery that has been sitting on a shelf with the chrony for who knows how long so a new battery will likely fix it and it cannot hurt it.

      BD


    • Rob,

      I had the same problem with a vintage Chrony when I was writing the R1 book. That’s why I bought an Oehler.

      I do want to test and document the problem, so others will know for sure.

      I throw out the anomalous velocities, too.

      B.B.


  18. I have owned the Diana NTEC in .22 and have tried Crosman 14.3, JSB 15.89 and RWS domed. So far at about 25 -30yards I achieve best results with RWS domed unsurprisingly however JSB is nice too. RWS will consistently enter by or over previous shot out of my Diana. Some complain of the trigger but I like the surprise break as I do on my Weihrauch HW90 .20. For the $ NTEC .22 comes very close to Hw90 .20 but sights are more simple on my NTEC Classic. Mr BB Have you tried any exotic pellets on your NTEC? If so what works?


  19. B.B., I had a thought last night as I was searching for an unused target, and finding none. What goes well with a tin of pellets? Why nothing goes as well as a pack of targets! So do you think Josh might do a four for three promotion on targets when bought with pellets?

    Yes, my strength and activity level are returning very rapidly. I was shooting my rifle last night and the pistol yesterday morning.

    If anybody wants to know what’s taking so long, drop me a private note. No need to spread it all over the world.

    Pete Z


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