Tech Force 87 underlever – Part 1

by B.B. Pelletier


The Tech Force Contender 87 is a big, powerful underlever.

Okay, now that Pyramyd Air also sells Tech Force airguns, I get to test them for you. Today, I’m starting to look at the Tech Force 87 Contender, a large powerful underlever that nicely compliments the TF 89 breakbarrel.

This is a very large spring-piston rifle. Dare I say huge? It weighs more than a Beeman R1 and is longer, too. According to the power level advertised, it should get 1100 f.p.s. in the .177 caliber I’m testing and 950 f.p.s. in .22. I’m excited to test this rifle; because when I tested the TF 89 breakbarrel that resembles this rifle so much, I found it to be an exemplary modern spring-piston airgun. I’m hoping this underlever will be the same.

As an underlever, this one has the sliding compression chamber that pushes the piston backwards to sear lockup when the rifle is cocked. Then, the shooter loads a pellet, taking care to restrain the underlever in case of a possible beartrap accident. You wouldn’t want your thumb in the way if the sliding compression chamber decided to suddenly close. But, the anti-beartrap mechanism is there to prevent any such accident. It’s the reason for three levers hanging down in the triggerguard.


Three levers in the triggerguard. The silver one is the trigger and the one in the middle is the automatic safety. The one on the left is the anti-beartrap sliding compression chamber release. When you’re done loading and want to slide the chamber forward, that lever must be pulled to the rear.

Stock
The stock is hardwood, stained a dark chocolate brown. The finish is even and without blemish. Uncharacteristically, there was absolutely no wood putty to be found anywhere. From past experience with Chinese-made argues, I looked at the alignment of the action in the stock, as evidenced by the position of the coking lever in the cocking slot. It was perfectly centered! And the checkering, while pressed and too slick to hold the hand, was also flawless. Somebody’s paying attention to this rifle at the factory!

The buttpad is a dark gray rubber pad meant to keep the rifle from slipping against your shoulder, but also from slipping when rested on the butt in the corner. It’s fitted as well as any European pad. A raised cheekpiece and Monte Carlo stock profile lift your head up for scope use.

The stock is not ambidextrous, but it looks like it could be shot by a lefty easily enough. The loading and safety are centered and don’t favor either hand. And the stock isn’t shaped to discourage a left-handed shooter.

Metal finish
The bluing isn’t as even as that found on a European gun, nor is the metal as well-polished. But the black oxide is very deep, which makes these criticisms difficult to see in anything short of bright sunlight.

Sights
The gun comes with a set of adjustable open sights with fiberoptics front and rear. But there’s also a scope rail, and it has a scope stop built in. So, you don’t need to worry about scope stops when you buy your scope mounts.


The scope stop comes with the rifle, so you don’t need to give it a second thought.


The rear sight adjusts in both directions but has an index for windage, only. It’s fiberoptic to compliment the front sight.

The underlever is held in place by a keeper that does not need to be released to pull down for cocking. Just grab it with your hand, and it comes away as it ought to. It also closes the same way, with no locking latch being required. There does appear to be an adjustment for the latch tension at the end of the fitting into which the lever fits.

I had to know how it shot
Part one of any test report is supposed to be about the features of the gun, but I was curious. I couldn’t wait to see how this rifle shot, so I fired it once. The feeling was remarkable, in that there was no great vibration or recoil. Just the smooth feeling of a powerful shot. And the trigger released reasonably, though with a little felt creep. I do believe I’ll enjoy testing this rifle.

The only drawback appears to be the cocking effort, which I’ll estimate to be 40 lbs. or so. I’ll weigh it when I test velocity for you. I also noted that when cocking this rifle, an extra pull is needed at the end of the cocking stroke. You’ll hear a definite click when the sear catches the piston.

Now for something completely different
Pyramyd Air no longer carries Ballistol, so what I am about to say will not benefit them. I’ve accidentally discovered a wonderful use for the stuff. Spray it into the bore of guns you have shot but not yet cleaned. It won’t remove copper or lead deposits, but it raises powder fouling like magic!

Spray it generously into the bore, then leave the gun alone for a week. When you return, you’ll discover that all the powder fouling has been raised up out of the metal and can be wiped out with just a cloth patch. It’s the easiest cleaning method I’ve ever seen, and these days I’m definitely looking for more of those!

115 thoughts on “Tech Force 87 underlever – Part 1



    • Markus,

      Like I told Milan, The TF 87 trigger is completely different. This is a Chinese design that looks like a takeoff of the AR 1000.

      Vince? What is this a copy of, if anything?

      B.B.


      • Sorry for kinda ducking out for a while…

        While I’d be first tempted to say that Shanghai has produced another Norica clone, a quick perusal of Norica models doesn’t seem to support that idea. The only underlever Norica seems to be the Quick (Hammerli Nova)… but I believe that rifle has the same ‘direct sear’ trigger that tarnished the old Hammerli Storm and the loading port is entirely different. The sliding compression cylinder and that forwardmost lever in the trigger guard area… very reminiscent of the heavy yet underachieving QB36-2/TF99, which also claims close to the same velocities.

        After staring at the pictures side-by-side, I’m wondering if Shanghai cooked up a bit of a Frankenstein – mating the AR1000 style trigger to the old TF99 platform. The Shanghai website (which generally has pretty realistic – or even conservative – velocity claims) lists the TF99/QB36-2 at 900/675fps. Which corresponds pretty closely to what BB got when he last tested one, I believe. But they list the AR3000/TF87 at 1000/750. So I don’t think that’s quite it either.

        I’m thinking they genuinely came up with a new model, with the design of the action perhaps based on the QB36-2, but improved and possibly enlarged. The old Compasseco website confirms that they do use the very decent AR1000 (Norica designed) trigger, which tends to be a little rough out of the box – but can be refined to a high level of sweetness with a little stoning. Of the trigger, that is.

        So this might really represent a spark of originality from Shanghai, a gun that doesn’t have a direct parallel outside the Chinese airgun world. And something on the better end of the scale to boot. If it is, it shouldn’t be surprising. T’was gonna happen sooner or later…



        • Vince,
          The TF87 manual has a parts list on the back cover showing the trigger assy. Perhaps B.B. can include a picture when he does part 2 of his report. With only 300 shots through my TF87-22 the trigger is still rough but predictable. In spite of this, it ( with open sights) has out shot a scoped Crosman Phantom,Gamo Big Cat, Walter Talon and a Remington Break barrel at 12 yards. Five Silver Bears/ H&N Hollow points punched one hole .375″ CTC in a paper target. I will try scoping it this weekend and see what happens. This gun can shoot.
          Pete


          • Pete,

            I’m looking at the illustration of the TF 87 trigger and cannot see how it would benefit anyone. I will show it, but it’s very confusing without the rest of the parts to relate to.

            B.B.


            • B.B.
              Once you show this picture, I can then ask Vince to point out which parts need smoothing.
              The TF89 and TF87 share the same trigger assy so owners of both rifles would benefit from this info.
              You might even want to do a blog on tuning triggers. Nudge! Nudge! Hint! Hint!
              I have tightened all the screws on the TF89 using thread tape and mounted a TF 4×32 scope and the groups are shrinking but the recoil is still horrendous-the scope has knocked off the scope stop twice already. I took out the two screws and the internal nut that anchors the two screws and replaced it with one screw and nut to be able to torque the screw to give the clamps as much biting power as possible. It is holding so far but I can see the rear ends of the two clamps starting to spread. My guess is that it too will go within the next 100 shots. The scope stop carries a pin on top but there are no holes on the receiver of the 89 to accept that pin. Perhaps PA can ask SAG to include a hole on their next run of The TF 89. I will look at the 87 to see if the configuration is the same and let you know.
              Anyway I am ordering a Leapers adapter and Weaver rings to try and correct this problem unless there is some other solution you can suggest.
              Thanks

              Pete

              Pete


    • OK, not Vince, but I can chime in because I have experience now!!! The AR1000 is the same as the Beeman I’ve been calling my RS2 which is more of the trigger designation and the model number for the dual barrel rifle they were selling. Anyway that RS2 trigger sure looks like the one pictured here on the 87. It is not a copy of the T02 trigger, I’ve taken apart both my RS2 trigger and my 34 so I can decisively say that they are not the same. Also, I’ve reviewed other dis-assembly guides online and it does not look like a Record trigger either. I believe it is its’ own design. That said, as it comes it is very rough internally. It seems like the design of the trigger is good, but the pieces inside are folded metal and the surfaces can be very rough and because they are folded, two pieces come together and for each trigger part and do not make flat contact with the adjoining part. I took mine apart completely and used a makeshift grinding stand to resurface the contact points. I made sure to keep the same angles and radius of the parts that make contact, but made the surfaces flat and smooth. Lubricated with a very little dab of moly, and re-assembled. There is also a double spring on the first stage of the trigger, a spring within a spring, that made the first stage a little stiff. I can’t say that the solution to this problem is engineered, so I won’t say what I did, but I can say that what I did made the first stage much much better. Now the trigger is fantastic!

      Accuracy still sucks though, I believe due to a mangled breech that requires manual force by a pellet seating tool to get the skirt flush with the breech. Vince has sent me a replacement barrel, so perhaps there is finally a happy ending to my RS2 saga…

      Wow, did I really just say all that!?!


      • Fused, yes, you found out the AR1000-style trigger secret. There’s one interface (it’s easy to see on a picture) that needs a little smoothing – and Bingo! – a budget Rekord.

        For the record, I always thought this trigger still feels a smidgen mushier in the 2nd stage than the Rekord, even after working it over a bit. But maybe that’s just me.


  1. B.B.

    It looks like Chinese-built Diana 460. Well, I’m third to say that πŸ™‚
    How’s the overall quality? Edges, barrel rifling and crowning, screws, metal quality and hardness (first of all – sears), anything rattling or rocking and so on. Chinese airgun makers sometimes sin on that part and that makes their production to have much shorter life. Anyway, if it’s well-made and it shoots well it can be a good cheap alternative to D-460mag

    duskwight


    • duskwight,

      I guess I need to come right out and say it. The build quality is excellent. I tried to say that when I talked about the stock, but of course the metal finish is a little off European standards.

      B.B.


      • B.B.

        Then we must see how it shoots. If it’s the same as Diana 460 – we’ve got a whole new great airrifle to prove that Chinese do not always make cheap scrap metal.
        I must admit they learn fast. Until now, one and only Chinese airgun I liked was B40, however it also had some things to improve – e.g. better metal for sears and cleaner surfaces. Besides that it looked, shot and felt like a real beau.
        Did you disassemble it? What’s the design of anti-beartrap mechanism and safety? I mean – how safe you feel it is technologically, as Chinese rifles with sliding chamber have a bit grim reputation.

        duskwight


        • duskwight,

          I have examined a disassembled B40 and the parts, while not finished as well as Air Arms parts, seem to be made nearly as well. The finish was what hurt the trigger.

          I can’t speak about hardening of any of the parts. But I do think their anti-beartraps are safe. Although I would never trust one, no matter who made it.

          B.B.




    • I like the MUCH cleaner trigger area and the safety right in front of my thumb with the Diana.
      This one gives me bad flashbacks. RS2 looking trigger and safety, Shadow looking scope stop.
      Too much clutter in the trigger area. Grooved for scope instead of a rail. Definitely not Diana.
      That’s on the outside. What about the guts?

      Might be good for the money, but it turns me off.

      twotalon


    • Gotta agree with twotalon and Mr. B. Similarities to the Diana 460 magnum are only superficial.

      BB, where can you get Ballistol? I have looked all over for that stuff?

      Hope this gun tests out better than most of the Tech Force guns I bought and then quickly returned. Only one I kept was the Tech Force 59 and it is so nice! Only bad thing I could say about it was the trigger and I fixed that with a Charlie Da Tuna drop in. Now it feels like an R9 rekord when you shoot it and it shoots like one also though it is a lesser powered gun so cocking force is milder and velocity is lower. Costs WAY less than an R9 though.

      Still have the TF 79TH on my wish list. Had one of those too and it was returned for bad seals. But that gun was a joy to shoot. Had a habit of hitting the 10 dot every time at 10 meters with the diopter sights provided with the gun. They are still available for $149 and are simply the most accurate gun I could find for any where near that price. Handled nicely and had a nice three screw adjustable trigger too! BB did you ever test this gun. If not, would you?


  2. BB,
    I’ve been excited about this one (AR3000, I think) for months. The trigger is a nice upgrade to the 36-x series, and it seems like the build quality is coming along as well, compared to not so recent IB guns.

    In this case, I would go .22 though. The older model 36-2 with a little work throws light (7gr) .177 pellets way too fast for decent accuracy, and this one has something like 30% longer stroke to piston. I don’t know if the out of the box seal, etc., will get it there, but I would place money on this one (in proper condition) being significantly more powerful than most .177 pellets can handle optimally. I will be looking forward to your results, and possibly a new project rifle :).


    • BG_Farmer,

      This is an AR 3000. The owner’s manual, written in Chinglish, says so.

      I, too, would go with .22 caliber at this power level. I didn’t have a choice. The guns are currently in short supply and they shipped me what was available.

      I only shot it one time so far, but from just that I can tell they got it right. The powerplant has a solid feel without vibration or bad forward recoil.

      B.B.


      • BB,
        I have to confess, I’m a big fan of the Shanghai manuals, and my training long ago in ancient and obscure languages is a true aid to enjoyment:). The dude in most of them is always wearing a PVC bomber jacket — so cool. I’m more careful not to load rusty nails, wire or small rocks now after reading a few.

        I wasn’t scolding you (of all people) about the .22 — I figured you take what you can get. Please test as heavy a pellet as you can find that works on the .177, though. Based on my redneck test lab results with the 36-2, I’m thinking the AR3000 may come very close to its rating with actual pellets, and the fact that I know what seals, etc., are likely required, this one should be a scream to tune up and tinker with if accuracy is good, although I’m guessing that the stock needs some chopping and slimming to be comfortable.


  3. BB,my Ballistol container,which is admittedly a little older,claims to dissolve copper,lead,brass,zinc and tombac??Is the aerosol different than the oil? It also claims to biodegrade in two years in closed container tests,which tells me I need more πŸ™


    • Frank,

      I based that comment on examination of the bore of my Peabody rifle, which I just cleaned this way. I can see lead on the grooves. I didn’t want to over-extend the benefits of the product. But if it also does that, wow! What a wonderful product.

      B.B.


      • Well,you have a barrel of proof…..literally.I’m wondering if mine has gone bad due to it’s age.The label
        states that it biodegrades or photodegrades in “aerobic decomposition within approx. 2 years” based on closed bottle tests.Definitely time to get more….even though I still have 11 oz.


      • BB & Frank: I use the Ballistol alot this time of year. It’s hunting season here and that means rain and snow , and condensation from cold guns brought into hot areas . I do the Balistol spray into the bore and set my gun muzzle down on a rag. Big problem with shotshells and slug loads is the plastic wad fouling. If water gets trapped underneath it in the barrel, it will rust there. Balistol creeps under this and prevents that from happening in my experience. I don’t think it dissolves it though, or lead fouling,Robert.


  4. BB:
    Should we all panic now and avoid the rush? lol
    When the Chinese start turning out good stuff like this Tech Force 87 appears to be,then the west is in serious trouble.
    I mean more serious than we already are πŸ™‚

    Off topic:
    Probably of no significance but when you look at the transfer port of any springer,it is always located off centre to the compression chamber.Unlike most bicycle pumps for instance.Which are centred.
    Barrel alignment and sights is what I guess dictates this but is is the cleanest way to transfer air through to the barrel?
    Thanks.
    DaveUK


    • Dave, I think the reason for the offset transfer port is that the barrel is not centered on the compression tube but is at the top of the compression tube.

      David Enoch


    • Hats off to Dave,This has always bothered me about transfer ports too.Maybe the gain from centering
      the transfer port costs too much ergonomically? That or it’s too small to notice.Maybe it just makes the front sight too high.


    • Dave,

      The Tech Force 89 has been on the market for over five years, and it is also a winner like this one. In fact, when I reviewed it for Compasseco I said Weihrauch needed to watch out. Because with the TF 89 the Chinese were already within striking distance.

      You are right about the air transfer port, which the Air Arms TX 200 has right. But the BAM B40 was a perfect copy of the TX and it did the same. I just got rid of a .177 B40 that was even more powerful and accurate than my personal .177 TX 200.

      So the Chinese can compete if they want to. The problem seems to be their own culture gets in the way. They would rather use hyperbole than produce products with the quality savvy buyers want.

      B.B.


      • BB:
        You have already guessed I used my old B3 as a template to build an air rifle with a centred transfer port πŸ™‚
        So the TX200 and B40 has done this already.
        Is that the secret to their success? πŸ™‚
        DaveUK




            • Milan:
              By the sounds of things the TX200 and the B40 already have a centred transfer port.
              We know the TX200 is currently one of the best springers on the market,so could this centred port be the secret as to why it is so good.
              DaveUK


        • Dave,

          I think the central port is one of Air Arms “secrets.” Actually, to give the devil his due, the praise belongs to Ivan Hancock, who pioneered the central port design that became the TZ 200, in a gun he called the Mach II. However at US$2,000 to 4,000, not many were sold. The TX 200 brought them to the masses.

          B.B.



          • Much like the Japanese and Koreans did (60’s and 80’s respectively) the Chinese can be great imitators and “copiers” of good designs. As BB said .. if their culture does not get in the way.

            We need to start worrying when they actually understand and practice quality control as regards the mechanical features that influence fluid-dynamics, such as transfer port locations and surface finishes, CTE of materials, etc etc.

            The Japanese abandoned the “copier” phase and went into the design and make for quality phase throughout the 80’s, and Dr. Demming was their quality “god”. Remember the 38% tanking of Mercedes Benz sales one year after the first Lexus LS400 hit the U.S.? Get ready for China.


  5. Success. I have had the dilemma that I wanted to have both long and short range sighting options, without guessing or calculating hold over/under positions. A scope is fine if time permits, but for short range mousing/pest control, that doesn’t always happen. Open sights, or dot sights work well, but I don’t want to remove my scope everytime, and rezero it later.

    Solution, mount a scope and close quarters sight at the same time. My scope is in the typical scope position, directly above the barrel so that the trajectory of the barrel crosses the crosshairs at a couple of points. Between the dual scope mount rings, I placed a 45 degree weaver rail and mounted a Walther holo-sight (one of the open glass dot sights). To use the holo sight, the rifle needs to be canted slightly, which throws off any long trajectory. That’s not bad, as the holo sight is only used for fast short shots, and I zero’d it to be tack driving at 10 yards, allowing for a relatively easy adjustment for closer shots.

    Position wise, it is fairly comfortable to shoot with either the scope or the holo sight, giving me short and long range accuracy. I’m really liking it, so far anyway. The holo sight is light enough that it doesn’t really throw off balance. Anyone else have any other solution that works for them, perhaps a better option? Admittedly, this is a little kludgy.


    • Bristolview,

      There is an easier way to do this. Mount your scope as normal, then buy one of those gamo adapters which allow you to mount a laser.

      Sight the laser for 10 yards or less. Even in the daytime you can see the dot on the target using the scope. Works great for me, though I prefer to sight the laser at 25′. The dot will always be close to where the cross hairs are but not exactly.

      This way no need to cant the gun.


      • I have done the laser thing too, that’s what I did before this approach actually. When used for pest control, the laser dot can spook some critters, and others see the bright light on the rifle. That spooks some, but not all. For close shots though it works like a charm. I guess the reason I stopped was that I have a cheesy laser that doesn’t hold zero well, but have a decent holo sight. I actually prefer the holo sight for close pest control, not that it’s any better really, just personal preference. Thanks for the tip.


        • bristolview,
          Again Ihave not read farther so this may have already been answered. I understand that if you use a green laser rather than red the animals don’t react to it.
          -CJr


        • Bristolview,

          I’m going to second the use of a green laser for the close range shots. That’s what is on my Talon SS. Works like a charm.

          A comment on the green color and scaring the target. When I’m shooting at the starlings I lase them until I see the refection of an eye and then squeeze the trigger for another head shot.

          Bruce


    • bristolview,
      Only thing I would suggest (I haven’t read past your comment yet so someoone else may have already suggested it) would be to mount a small laser on the sight and use it for short stuff. Might be a little less klugy and might work at a lot of distances.
      -CJr


  6. Okay…I’m going to throw this one out for all the magnum guys.
    I’ve just started reading a book that is meant to supplement the U.S. military FM-23 sniper manual.
    In this book he talks about how a sniper deals with bullet tumble as it goes from supersonic to subsonic…and how once this happens the accuracy of the round falls apart.
    So it would appear it really doesn’t have anything to do with pellet design…diablo vs boat-tail…any of that. It would seem that the limit of extreme accuracy falls off the moment it goes subsonic.
    Soooo…a round exiting the barrel at 3000fps (.338 Lapua) is accurate to 1000/1200yds because it holds supersonic to about that distance.
    But a lightweight .22 pellet at even 1200 fps looses speed much quicker, because friction from air slows down the lightwieght pellet (when compared to the .250 gr lapua round) within a very short distance (under 100ys??)
    I quess my point is…why even bother with these Magnum/PCP guns? It would seem that unless we can get the speeds well above supersonic (minimum 1600/1700fps), they enter the subsonic speed range far to early to be of much use.
    Or am I missing something.



      • Matt, that’s my point. I would think from what I’ve read that 100yds or thereabouts is the limit for air power.
        The reason I brought this up is that there is a big discussion on another forum (which I seldom visit…promise πŸ˜‰ ) that has a bunch of people postulating that if you could build a better pellet…spitzer or boat-tail or whatever…that you could make a magnum springer or PCP accurate out to a couple of hundred yards.
        But from what I’ve gathered from the book I’m reading…no matter what the shape you make the ‘pellet’, once it drops to subsonic the accuracy falls.
        I’m thinking (and could very well be wrong) that this is one of those instances where the only thing that is going to do it is raw horsepower…and I don’t think any air powered gun currently made has the jam to keep the pellet (even a fancy shaped custom one) supersonic at 200 yds.


        • The current pellet designs lose speed so rapidly due to their un-aerodynamic design, which is necessitated by their need for drag stabilization. Spitzer pointed, boat-tailed bullets are literally an order of magnitude or more better, and will not lose velocity anywhere near as fast, but they require different twist rates and longer lengths for stability. The main limitation out of air rifles would be that the low initial velocity will still result in a loopy trajectory.


          • Actually, just try an experiment in Chairgun, comparing velocity of 2 similar pellets, but first make a new pellet by copying an existing one and giving it a BC of .3 or so (some spbt bullets are quite a bit higher). The difference between them will be obvious on the graph. One other consideration I forgot is that the real problem for some projectiles is the transonic region, roughly 0.8 to 1.2x speed of sound. As they decelerate to this velocity range, they are terribly unstable. High-velocity pellets and .22LR bullets are horrible in this range, but they enter it quickly because they slow down so fast.

            A good aerodynamic bullet design, however will start above that range and stay there for the extent of its useful trajectory.


      • Magnum PCP owners buy and shoot the heaviest accurate pellets or slugs that still shoot fast enough to have a usable flatness to their trajectory at the desired range.That weight can go over 500gr.,for example,and deliver plenty of energy to the target because they don’t loose much velocity if well chosen.


        • To add to what Frank B. said, that “fast enough” point is still sub -onic, so the pellet never goes through the transonic speed region. Sure, some will shoot lighter pellets that go above the sound barrier for kicks, but for accuracy they stay well below the sound barrier. And with the accuracy, they can put the pellet pretty much where they want it.

          The discussion of “better shaped” pellets is really about getting a higher BC so the speed stays higher longer, allowing a farther reach with a flatter trajectory.

          Alan in MI


    • Cowboy,

      The point to a magnum springer or very high powered pcp is to use a very heavy pellet that starts and stays subsonic and hence maintains accuracy. As a bonus it does not slow down as quickly as a light pellet of equivalent caliber would nor is it influenced as much by the wind. Another bonus is its terminal performance at the target. Much better knock down power.

      So take for instance my .177 Sumatra 2500 carbine. At highest power using the Eun Jin 16.1 gr pellet it develops around 975 fps. Subsonic for sure and that gives me around 33 ft lb of energy. More than double what my brother’s Gamo Big Cat with 7.9 gr domed pellets at 955 fps develops. Flatter trajectory and more accuracy and better knock down too. What’s not to like about that?

      That is the appeal of “magnum” airguns.


      • pcp4me…perhaps I have not made myself clear. I realize that if you can push a heavy pellet it will give more knock-down power…good!
        The posting in the other forum was all about pushing a pellet supersonic with a magnum gun…and it’s the supersonic bit that I have difficulty with. It seems that any of the guns that do this are not know for thier accuracy downrange.


        • Cowboy,

          Yeah, I bet if you push a pellet supersonic it is not accurate down range. For sure! This is some thing which has been know for a long time. But some people think that if they keep doing it enough they will have different results. Or if they just had a different weight/shape/composition pellet that it will be accurate at supersonic speeds!

          DOH! “Stupid is as stupid does!”


          • PCP4Me
            Could you explain to this dolt why a properly designed supersonic projectile from an air rifle can’t be accurate, other than the fact that it hasn’t been done yet?


            • bg farmer….it’s not that it can’t be accurate…as long as it stays supersonic. As the book I’m reading states, even the .338 Lapua, once it transistions from super to subsonic likely will tumble and lose it’s accuracy.
              That was the original intent of my questioning. Some Magnum .177 springers claim 1200/1300 fps second (supersonic), with things like the very lightweight Gamo Raptors. But they are so lightweight that they go subsonic very soon after they leave the barrel and lose all accuracy.
              My point was…what’s the point πŸ˜‰ …or was I missing something (which it seems I’m not). Just a case of the ‘horsepower’ war that is really counterproductive.


              • I see, I think:). You’re right — no drag-stabilized pellet will stay supersonic long enough to be worthwhile. For a while, however, I’ve been interested in making a PCP with specially designed projectiles for short-range (~200 yards) benchrest type use, but it wouldn’t use diabolo pellets. I think that is possible, at least, and would be an interesting application for air power.

                Incidentally, regarding the tumbling of the .338 at 1000-1200 yards, consider that it has by that time probably dropped 30+ feet (and then there’s windage), so its utility is marginal for most applications at that range even if the accuracy was 100%. I guess it is a problem for military snipers, but they have better tools than we, including the .50 cal’s :).


        • Guys,

          This was one of the most interesting discussions that I’ve had the pleasure to read! Great arguments regarding supersonic, or not.

          The point that a projectile won’t stay supersonic, and thus tumble is a good one, but wouldn’t this exact same thing happen with a sub-supersonic air rifle? I mean, isn’t supersonic just a higher threshold for speed? Would a sub-supersonic projectile also eventually start to tumble and become inaccurate?

          Would a pellet start to tumble sooner because it was fired at a supersonic speed?

          One question that I would have is, how far would a pellet go before it starts to exhibit instability (i.e., tumbling) for a supersonic versus sub-supersonic initial velocity?

          Is it possible for a pellet flying at supersonic speed to perform better than one at sub-supersonic speed for some percentage of the distance aimed at?

          This can be an important question for a hunter, I would imagine.

          Suppose we have two highly accurate air-guns, one supersonic and one sub-supersonic, where the supersonic is more accurate (even if only slightly) at a shorter distance of, say, 25 yards. It would be interesting to know at which point the supersonic pellet becomes less stable and inaccurate than the sub-supersonic. Would that happen at 35 yards? 50 yards? Further?

          If I was a hunter, I’d want to know this, even if just in theory. This would define the effective range of my gun, and possibly choice of pellets.

          Thanks,
          Victor


          • Thank God i am not physicist πŸ™‚ but pellets are NOT DESIGNED for supersonic speeds ,we already had this discussion before ,airgun pellets are not carbine rounds aerodynamic and heavy their skirt make them unstable and why would you go supersonic -your gun would behave like fire weapon -noisy


          • Victor,

            I was wondering if our resident rocket scientist, Jane, would come to the rescue here or Herb the Chem E or even Pete Zimmerman, the Nuclear Physicist as respects how quickly a pellet slows down from supersonic to subsonic speeds. But no luck. I can probably figure this out using available ballistic formulas from physics. It will be an approximation because the formulas only use the ballistic co-efficient or air drag and not skin drag for the pellet. I’ll also assume an initial velocity of 1600 fps (supersonic) down to 1,000 fps (subsonic).

            I’ll get back to you in a few days.

            Fred PRoNJ


            • Fred,

              My thoughts are that the disadvantages of shooting a pellet at supersonic speeds are related to the shock wave that would be experienced on the pellet, and nothing more. I would not consider anything remotely like a flat-head or hollow-point pellet for this experiment, because they introduce additional issues of drag and instability.

              Looking at , http://en.wikipedia.org/wiki/Speed_of_sound, I see that the speed of sound is 1,126 ft/s, which is by definition “supersonic” because, “The speed (in distance per time) divided by the speed of sound in the fluid is called the Mach number. Objects moving at speeds greater than Mach1 are said to be traveling at supersonic speeds.”. So we’re really talking about speeds under and over 1,126 ft/s.

              Thanks!
              Victor


              • Victor,

                I agree with everything you say. The problem with a supersonic pellet is the instability it will suffer as it passes through the sound barrier – we have been told that a wobble or tumble is set up from which the pellet is unable to recover (same for bullets as Jane – who is a rocket scientist and knows a thing or two about fluid dynamics – has indicated and we’re been told by others) regardless of spin stabilization.

                I thought your question was how far would a supersonic pellet travel before dropping down below the sound barrier and that’s what I was going to try to solve. For true accuracy, this equation probably requires differential equation analysis (something I haven’t used since 1972) but we can do an approximation. I chose the two speeds – 1600 fps inital and 1000 just to plug into an equation to solve for time. Typically, my feeling is that the pellet would travel less than 10 yards before dropping down to subsonic speeds but this is an interesting question that would further resolve the issue of why not a supersonic air rifle, sound issues aside.

                Fred PRoNJ


            • You know what would be perfect for such an experiment? An air-rifle that could fire at speeds both over and under supersonic.

              I know that it would be relatively easy to test this with a 22 caliber rimfire,
              because you can easily find target ammo that fires at under 1100 ft/s, and it would probably be just as easy to find something that fires at 1200 ft/s. Very interesting!

              Does anyone know of an air-gun that can be set to fire at two different velocities, above and below 1126 fps, with read pellets?


  7. Hi BB,
    For easy cleaning of powder burners, I’ve been using a Hoppe’s bore snake. I use an eyedropper to put a few drops of Hoppe’s no. 9 on the little wire segment, and then spray the whole tail of the bore snake with Ballistol. Two or three pulls of this rig seems to do the job.


  8. B.B., I’m glad you are doing the Tech Force reviews since I used to enjoy them on the Compasseco site. I was very tempted by the model 125 something or other breakbarrel which shot a .25 in. group at 25 yards.

    Well, I’m encouraged by the reloading response. Safety is my priority, and I’m willing to trade a great deal of time and effort for it. On the other end of the spectrum, I was reading about Indians in frontier times who dealt with restrictions on firearms by white settlers by reloading their cases pretty much forever, 30X at least. But I suppose they and the buffalo hunters were not into long-term health care. Also on the subject of reloading, I see that the accuracy load for the .45 ACP in the Lyman manual which calls for 700X powder has a velocity of 676 fps. That’s about like a Crosman 1077 with a 30X heavier bullet.

    I checked more into the California law on ammo restrictions which will go into effect on February 1, 2011. The good news is that the law is restricted to handgun ammunition and, more importantly, that the limit to 50 rounds per month was struck down. (Incidentally, ammunition is defined to include bullets by themselves, so reloading would not have helped.) I don’t see how they could have retained the 50 round limit since that’s not nearly enough for practice. You may as well just turn in your guns at that point. The bad news is that internet sales of handgun ammo are banned to satisfy the provision for face-to-face transactions. Handgun ammo is also defined to include .22 LR which will impact the specialty ammo I want for my Anschutz, and reloading will not help here either. Man, does this suck. Hopefully, the law will get repealed shortly. There are already some lawsuits filed, challenging the bill based on federal jurisdiction over interstate commerce.

    I notice that the anti-gun movement seems to make a distinction between hunting guns which they don’t seem to particularly care about and handguns and assault rifles which bug them extremely. Someone needs to show them how much fun this is.

    Matt61


    • Matt,
      Fun won’t convince them. The main reason they want to disarm the citizenry is the primary reason the 2nd amendment was written; you have to look beyond the surface in both cases.


    • Matt61,

      Actually the break barrel they claim that accuracy for is the TF 59. Here is the quote directly from their site: “If your taste in air rifles runs to moderate power with stunning accuracy (Average group when tested at 25 yards was Less than .25″), here it is.”

      I happen to own one, and their accuracy claims are too modest. The gun easily shoots 25 yd rested groups of .25″ ctc and when I do my part an occasional one of .12 – .18″ ctc. Stunning accuracy indeed! And the cocking force is very light. But with chps it only does about 725 fps. I did install a GRT III trigger in it, but is is scoped with a cheap 3 X 9 X 32 fixed parallax Center Pointe scope. Who knows what might be possible with a higher power target scope? And it shot those kind of groups without the GRT III trigger too. It was just easier with the trigger upgrade. I can actually shoot almost as well with it at 25 yards as I can at 25′ in my basement. But in my basement only have a wobbly card table to rest it where as at the range they have good solid rests.

      That gun by the way will be for sale on yellow forum soon as I bought a Crosman Storm XT for $54.95 which is every bit as accurate and has more power. It now has the GRT III which was in the TF 59. I have decided to go almost exclusively with CO2 and PCP as my arthritis makes extended sessions of cocking and firing break barrels painful.

      So I am keeping only one break barrel and that will be the Crosman Storm XT as it is lighter than the TF 59, about 150 fps more powerful, and every bit as accurate. Already traded my R9 and sold the Blue Ribbon 66R scope on it for $200. So soon the XT will be the only break barrel I own, though later I may supplement that with a Titan GP from wally world. I read some great reviews on line about that gun. If I get one it will be .22 caliber as the XT is .177 caliber.

      But right now any spare money I get my hands on will be going to a carbon fiber tank and fittings for my pcp guns!



      • PCP4ME, or B.B.,

        I just saw the Titan GP at Walmart for $10 dollars less than the Titan sold by PA. The GP is advertised as shooting up to 950 fps with non-lead pellets, whereas the PA Titan says 1000 fps. However, PA also has a lower-velocity model.

        What is the difference between the Titan GP and the Titan sold by PA? Are they the exact same gun, or is Walmart cutting corners somewhere? Why the 50 fps slower rating? Is this just a more conservative (and more true) rating?

        I believe that Walmart will charge tax on top of the cost of the gun, so in most states, you might end up paying more than if you bought it at PA. The Walmart price that I saw was $156, whereas PA’s is $166. This is a 6.4% difference (less than any state tax that I know of), and when you add 50 fps, PA’s version sounds like a better deal.

        Any input?

        Victor


        • Victor,

          I don’t know whether there is a difference between what Wal-Mart sells and what Pyramyd Air sells or not. You would have to be on the inside to know something like that.

          I do have a Titan GP in .22 caliber on hand to test for you. I chose the .22 in the lower velocity offering because of what the lower velocity does for the performance. I am hoping that it isn’t too different than the Benjamin Legacy, which is a gas spring to die for!

          The rifle I have is blister-carded, just like a Wal-Mart gun, so I suspect they are all the same.

          B.B.


        • Victor,

          I’ve been in contact with Crosman, and Pyramyd Air had the wrong velocity for their .22 Titan. It’s 950 fps, not 1,000. I’ve corrected the product page.

          Thanks for bringing this to our attention!

          Edith


      • B.B.,

        I know that PA once sold the same gun as Walmart, the GP version. I’d like to think that there shouldn’t be a quality difference if PA once sold the GP. I have to wonder if the difference in stated velocities is real, or just one case being more honest than the other. I’ve read lots of reviews of the GP, and it seems that Crosman hollow point premiers shoot at around 740 fps.

        I am curious as to what kinds of numbers you get B.B.

        Another thing that I’ve read is that there are a fair amount of defective units from Walmart. These defects express themselves as anything from extremely poor accuracy to non-functional.

        I think it would be very interesting if you could test both the PA version and the Walmart version. I’m guess that they’re the same gun, both over stated, so one being more true.

        Thanks,
        Victor



  9. I’m convinced this gun is NOT for me.

    B.B. is a big guy. I ….. am not. In fact my Gamo Delta, a youth gun, fits me well. I want to get a Big Cat someday, and that’s about as big as I want to go. I suspect this gun is at least as much bigger than a Big Cat than the Big Cat is larger than my Delta.

    I got my Delta because a lot of the time, you don’t want to have too much power. You need a mild gun. I ran into this problem a few years ago, wanted something to plink with, got some RWS I forget the model, from a friend, and it was too powerful for the kind of plinking I was able to do on the land I was on at the time, and so I hardly shot it.

    That being said, while my Delta is fine for birds even crows with good shot placement, it’s just not effective on possums, and would probably only annoy a coon. Frankly that’s getting up into .22 rimfire territory. As mentioned before, .22 round nose bullets just sail through, Remington’s “Subsonic” load, a standard-velocity load (I suspect it’s their Target load) with a hollowpoint isn’t too noisy and gets the job done. But if you can’t or don’t want to own a firearm, this Tech Force beastie ought to get ‘er done using Beeman Kodiaks or something.


    • Flobert,

      B.B. USED to be a big guy. I’m still the same height, but I lost most of my muscle in the hospital. I find this rifle very large and difficult (for me) to cock. That said, it has a very pleasant shooting behavior.

      B.B.


  10. B.B., Maybe it’s because everyone else has better judgement (or taste) to bring this up, than do I – as such is often the case. But, my browser caption reads: “Nov 3, 2010 … Before I start today’s report, Joe B. in Marin and Duskwight were really impressed by that air bazooka I showed on the blog for Day 2 of the …”

    I share their interest. Just can’t seem to find that comment, or what follows, anywhere in today’s blog. Set me straight, here.
    Thanks,
    Perk


  11. Hoppe’s makes makes bore snakes in two versions one for 17 cal.firearms that includes the brass brush,and one for airguns without the brush. Doe’s anyone know why this is? Hope I’m not scratching up my bore but they sure work great.I wish pyramyd would stock them.


  12. B.B.

    I made a little investigation concerning this rifle.
    So…
    It seems to me that it is sold in Russia as Shanghai QB-36-2 or Hammerli-900, and this model is its new upgrade with better quality. Its trigger unit is basically copied from Norica Marvic.
    So πŸ™‚ I must take my words back – it is NOT a D-460 in any technical aspect.
    My apologies.

    duskwight


  13. For Loren,

    My guess is that the bore snake with the brass brush is is fine for any steel barrels, and the “airgun” snake is for brass barrels, such as on the Benjamen 392, Sheridans, and some other older airguns. Brass is a lot softer than steel, and you don’t want your cleaning tool to scratch the bore.
    –Mike U



  14. One of the best bore cleaners I have seen in recent years is M Pro 7. It’s low odor and cleans very well. It should work on air gun bores. I also use Ballistol, it’s a good product.

    Mike


  15. I forgot to mention if you have a rifle like the Marauder with a breach seal inside the pellet chamber do not use the bore snake with the brass brush. It will chew up that “O” ring.
    _ Loren


  16. B.B.
    If the 87 you are testing is anything like my 87-22, you will be very pleased with the results. All of the readers of this blog will be pleasantly surprised when the final numbers come in. The greatest compliment that i could pay to this gun is that i would buy it again! Good looks , power, accuracy, great price. It is time to fall in love again guys!


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