H&K MP5 K-PDW CO2-powered BB gun – Part 2

by B.B. Pelletier

Part 1


Umarex HKMP5-K-PDW is a lightweight, handy BB-firing semiauto.

Well, now that I’ve shot the HK MP5 K-PDW, I have a greater appreciation of what it is and how it functions. The stock removal required to replace the CO2 cartridge is troublesome but not time-consuming. However, while I was shooting, the CO2 started to leak, causing me to have to tighten up the screw that puts tension on the CO2 cartridge. This is the first time I’ve ever had to do this in tens of thousands of CO2 cartridges, and it was unexpected, except that I read about it in the customer reviews when they rated the gun. So, I suspect this behavior is common to this gun.

The stock pins are now worn in enough to easily press out with my fingers. They’re still difficult to align when putting the stock back on the gun, but a plastic hammer will tap them into place quite readily.

Don’t do this!
Now let me tell you a weakness of this CO2 cartridge installation system. When I loaded a cartridge I forgot to loosen the screw all the way before pushing the pins back in the stock, and I pierced the cartridge as I was installing the pins. It is written clearly in the owner’s manual to not do this, but I thought I knew what I was doing. So, I exhausted an entire cartridge with no effect. Remember to back off the CO2 piercing screw each time you remove a CO2 cartridge, and you won’t have this problem.


This screw pushes the CO2 cartridge into the piercing pin. Don’t forget to unscrew it all the way before you put the stock back and push the pins in place, or it’ll pierce the fresh cartridge before you’re ready.

Number of shots per cartridge
I got about two complete magazines per CO2 cartridge, but the last shots were not in the same power band as those in the first magazine. They were still in the 300 f.p.s. range and above, though, which makes them credible shots on a close-range course. The real drop-off doesn’t occur until a third magazine is attempted, so don’t try it.

Loading
I found loading was easy and straightforward. The follower release is located on the bottom of the magazine, and until I found it I couldn’t get the follower to move. But once found, the button works fine. So, familiarization with the gun is important. However, loading takes long enough that I can see why owners want to buy extra magazines for their guns. It would be so simple to pop out a spent mag and replace it with a full one. And since you get two mags worth of shots per cartridge, it seems like two mags are the ideal number to have.

Velocity testing
I tested both Daisy zinc-plated BBs and Crosman Copperhead BBs for velocity with the HK MP5 K-PDW. You might think that all BBs are alike, but my testing experience over the years has proven otherwise. In this test, Daisy zinc-plated BBs averaged 430 f.p.s., with a range from 424 to 438 f.p.s. Crosman Copperhead BBs averaged 435 f.p.s., with a range from 427 to 446 f.p.s.

So the Daisy spread was tighter, but Crosman BBs went slightly faster. What will that do to their respective accuracy? We won’t know until we test them both, of course, but I would expect the BBs with the tighter spread to group closer together. However, we’re talking only a few fps difference.

Looking at the advertised velocity, I see that the results show a much greater potential than they advertised. I’m surprised to have gotten as many shots as I did at this elevated velocity, except that the longer barrel on this gun may have improved the gas management.

Magazine lockout
I discovered that at the end of the BBs in the magazine, the trigger locks up and will not function. It isn’t like the safety has been applied, either. When the safety goes on under normal operation, the trigger loses all contact with the firing mechanism and simply moves back and forth under the force of the trigger return spring. But, when the magazine is empty, the trigger is blocked from moving at all, whether the safety is off or on. It’s a nice feature for a fast-firing semiauto because you won’t waste any ammo.

Blowback
I think you can forget about the blowback feature. It’s there, but there’s not enough reciprocating mass to feel the impulse. The gun simply pulses when it’s fired. I even turned it sideways so I could watch the ejection port cover move open when I shot. The action underneath this cover is silver, so you notice it in contrast to the black plastic of the cover itself. I could see it move, but was completely unable to feel any blowback action in the gun. I guess the good news is that a lot of gas isn’t wasted by this miniscule movement.

View…so far
Well, I like the light weight of this gun compared to the firearm. I don’t care for the non-HK rear sight, which puts a notch too close to the sighting eye. The regular HK rear aperture would have been the best way to go.

The power was surprising, especially in light of what’s advertised. You’ll want to be extra careful with this BB gun, as it has enough velocity to do damage at long ranges. And, of course, it needs to be said that you must watch out for ricochets, because this gun has the power to send them back at very high velocity.

The method of CO2 cartridge installation leaves me cold. It works and it isn’t hard to do, but it’s very clumsy. I would much prefer to just drop a cartridge into a hole and screw the cap tight than to remove the buttstock and have to assemble it every time a cartridge needs changing.

79 thoughts on “H&K MP5 K-PDW CO2-powered BB gun – Part 2

  1. Tom,

    I want to display some of my woodwork at Roanoke this year, but I haven’t been able to reach anyone at the phone number published in the flyer for this year’s show. Do you have an alternate phone number for contacting them about a table? My email is mchavka@hotmail.com. Thank you in advance.

    Michael Chavka


    • Michael,

      The community is clamoring for left-hand ten-meter grips for the IZH 46M. If this is something you can make, please bring a sample.

      Also there is no end of interest in 2240 grips or stocks for Discoverys and Katanas.

      People really go for custom woodwork.

      B.B.


      • Yeah, let me add my clamor here, too. Clamor, clamor, left hand grip. The texas people won’t even make me a grip unless I buy the pistol from them, too. Something about mounting screw problems with different IZH-46′s. BTW, my hand width at the knuckles is only 80mm, I wear a small glove.
        -CJr


  2. Morning B.B.,

    Tell Mac that I said thanks for the tutorial he gave you with your camera. Great pictures these days. I’ll be curious to see how the accuracy of this gun compares to the IZH Drozd.

    Bruce

    PS Edith, The delete comment that I mentioned a couple of days ago would have allowed me to remove this comment now, but once I hit Submit Comment the comment was published and unable to be deleted by me.


  3. Okay, so now I’m a little leery. The loading sounds like it will be horrendous for a 7 and 9 year old. Though I usually help them load their cartridges in their pistols…the 9 year old especially has reached the point where he wants to do it himself.
    But they want something ‘cool and tactical’.
    So this begs the question…does anyone have any experiece with the Umarex Steel Storm…the other gun that was on their list.
    Which, in your opinion would be easier for a young person to handle…or is their any difference.


    • CowboyStarDad

      Check out the video for the Steel Storm on the PA site, on the product page. Also, (IMHO) this H&K look alike is just to contrived in it’s operation and reloading methods, both BBs and the Co2 carts. I’m 57 and dont want to deal with it, imagine the patience level of 9 yr olds!?

      The plastic pins in the stock and other features seem less than robust in design and overall too much $$ compared to the Storm.

      PS The Storm also has a 6 round burst mode


      • Gotta admit, I’m tending to agree with you Brian. And I checked out the vid on Pyramyd…the Storm seems very accurate, and the 6 round burst is cool.



      • I spoke today to my a gentleman on the order desk (unfortunately, though I buy all my accessories from Pyramyd, they won’t ship air rifles/pistols to Canada) I purchase from. He has shot played with both the MP5 and the Storm and says that a child will definitely have an easier time with the Storm.


        • Speaking of all those BB tactical got me looking and the Storm seems REALLY interesting but seems to be missing one important feature… a shoulder stock. Shoulder stock that does come with the drozd but the drozd seems kind of a pain to load compared to the storm wich has a nice BB reservoir.
          I’m not really helping am I…
          Personally I think I would go for the storm and try to find a shoulder stock for it. Then again I’m not a 7 or 9 years old kid.

          J-F


  4. Wow I got totally lost in blogville. This question ended up somewhere else but meant it to be here, my fault:

    I need help searching this blog. I never seem to find what I’m loking for although I know it’s there. Today I wanted to find articles and comments on the IZH-46, specifically on what pellets seem to work best, but the only hit I get is on “Looking back at the FWB C-20 pistol – Part 3″.

    Any suggestions? Any tips on how to search past articles?

    -CJr


    • CJr,

      If there are IZH-46 articles on this new blog format, they’re not coming up because they don’t yet have tags or categories attached to them that will allow them to come up. Here’s how to find what you want in the previous blogs:

      1. Scroll down on any blog page until you see the HISTORICAL ARCHIVES header in the right column.

      2. Click on one of the months in a previous year.

      3. That will take you to the blog we used to have on Blogger.

      4. In the right column, enter your search term(s).

      5. I just did such a search, and found 264 references to the IZH-46. Click on this link to take you to that search page.

      6. Enjoy!



  5. MY SUGGESTIONS FOR SEARCHING THE WEALTH OF INFORMATION ON THE BLOGS

    CJr asked a very relevant question since not all the articles from the old blog have been transferred to the new blog.

    I use Google to search. On my opening google page, on the right side in very small blue letters you can click on “Advanced search”. When that window opens you have several options of how to search. I usually use “all these words” to type my criteria.

    Here’s the trick. At the bottom of the google Advanced search window you have the option to “Search within a site or domain:”. Narrow your search to the Pyramyd Air Blog only. To search within recent articles and comments I copy and paste the current blog address into the “Search within a site or domain” box:

    http://airgun-academy.pyramydair.com/blog/

    To search the wealth of information still on the old blog I use the old address:

    http://www.pyramydair.com/blog/

    kevin


  6. Edith, Kevin,
    Thanks for the info on searching. I was able to use Edith’s technique on the history items and get hits on articles and comments both. Kevin, your technique does work on the new stuff to get both.

    BTW, Mr B in searching I found this:

    Quote:

    From Mr B. Says:
    May 11, 2010 at 9:16 am

    Chuck/CJr,

    A question on converting Mr T to HPA–you said the converson stuff, is that a plural stuff or is it just the HPA tank? The reason I’m asking is, when I bought my Talon SS it came with a free CO2 adapter, but no other stuff for using CO2, and I was wondering about hammer weights, ie, are they the same for HPA and CO2?

    Thanks,
    Mr B.

    End Quote

    Did I ever give you an answer on this? I couldn’t find it in that article.

    If I didn’t: All I did was buy the HPA tank. I took the CO2 adapter off and merely screwed in the HPA tank in its place. I did not change any hammer weights. Do you know if this is necessary?

    -CJr


    • Hi CJr,
      I just noticed your question about large dial gauges from the other day in “How many shots per fill”. I put a response in the comments there.
      Lloyd


    • CJr,

      Better late than never. Now I can get rid of the window sash weight I’ve been using. I was being lazy lately and shooting my Talon SS and Benjamin Discovery on CO2 until I realized that was like ringing the dinner bell for those voracious Tiger Mosquitoes that have taken over this part of Maryland. I open my back door and shoot across the yard. Those little vampires followed the CO2 trail right into the house. Can’t wait until the first killing frost!

      Thanks to Edith, CJr and Kevin for the advice on searching the blogs.

      PS Edith the Click here to cancel reply is back up–go figure.


      • Mr. B.,

        The “click here to cancel reply” shows up only when you reply to another person’s comment. It does not show up when you simply want to submit a comment that’s not a reply to a previously made comment.

        This has nothing to do with the previous comments I believe you made about deleting a comment. Deleting a comment is made AFTER publication of a comment. Cancelling a comment is made BEFORE you submit a comment.

        Edith


      • Mr B,
        Now that is too funny! I knew mosquitoes followed exhaled CO2 to their mammal victims until they could home in on the body heat but I never even dreamed they’d follow the CO2 from an air gun, but it makes sense. Just think of them as challenging field targets.
        -CJr


  7. On the subject of the tactical configuration, I recently compared shouldering my M1 Garand and my IZH 61 which is much shorter and has a pistol grip. The M1 was actually a little easier because of its balance and clean stock. But I may be biased. Those comments about the short LOP on combat rifles make a lot of sense. The M1 buttstock is shorter than I would have specified, but it works fine.

    PeteZ, you must be right about variable powder charges contributing to vertical dispersion. On the other hand, I would still expect anything other than a constant wind at a fixed distance to contribute to horizontal dispersion. It is not uncommon at all for long range gun testing to measure only vertical displacement for this reason; so the wind is not insignificant. I would be a little surprised if variable powder charges outweigh the wind enough to consistently elongate groups vertically. However, it’s all in the numbers and I wouldn’t know. At any rate, the variable powder charge must be the mechanism for the vertical dispersion; I don’t know what else it would be.

    Regarding bullet shape, if I’m understanding wasp-waisted correctly, that means the bullet narrows in the middle then flares out at its base. That would run counter to Yuryev’s theory. I’ve never gotten into fluid flow which is a very difficult topic, but his story is that part of the flow pattern around bullets is that a suction is created at the base of the bullet. The smaller the cross-section back there, the less drag which makes sense to me. Of course there is a minimum point below which the bullet will not catch the expanding gases efficiently in the barrel. Hence the boat-tail shape. And this would seem to rule out wasp-waisting.

    Matt61


    • Matt,
      Spitzer point and boat-tail (or even pointed, which is impractical, as you point out) is pretty much optimal for supersonic; tear drop is best for subsonic. Think Cessna vs. rockets. I think wasp-waisting on some designs may have to do with transonic stability (which is of little concern to c/f bullets, spending their useful lives in the supersonic region).

      Powder charge/bullet velocity affects both vertical and horizontal displacement in real life. Loading up a rh-twist barrel will usually send a projectile to the right of original POI, loading down to the left, if my dyslexia is under control today. I’ve seen several cases (probably depends on range and wind conditions) where the lateral displacement was more remarkable than the vertical.


  8. BB and All

    Your input / comments please.

    Beeman P3 pistol versus the “Beeman P17″ pistol (Marksman 2004?)

    Other than the China manufacturing of the P17, is the accuracy, trigger, barrel and materials of construction the same? (notice I didn’t ask if the Chinese fellow who made the P17 has the same attention to detail or interest in it as his German counterpart who made the P3′s!)

    All comments appreciated.

    Brian in Idaho


    • Brian,

      Mac and I haver talked about this comparison. I own the 2004 that became the P17 and he owns a P3. We decided that his trigger was crisper than mine, but my gun is more powerful than his. They are both accurate.

      I’d say the risk with the P17 is the QC issue, which is a gamble. But how many P17s can be bought for the price of one P3?

      B.B.


      • BB exactly!

        One other question please… After shooting the P3 for some time, I notice it (occasionally) loses compression after cocking or… occasionally loses it’s charge if sitting around for a few minutes between shots. Would there be any benefit of machining an additional o-ring groove behind the single o-ring groove in the piston? (I have access to a lathe) Then… install a second o-ring. My guess is approx. .125″ from the rear face of the stock o-ring position.

        Guess I’m thinking along the lines of an automotive piston that has several compression rings above the oil ring?


        • Brian,

          To work an o-ring needs a channel cut to the proper proportions. Since there is none in this pistol, the addition of an o-ring won’t help the situation.

          The situation is helped by frequent oiling and by not leaving the gun charged longer than five minutes, because the inlet valve is also the reservoir valve. It cannot remain pressurized for a long time.

          B.B.


          • BB By “channel” do you mean an additional feature cut into the piston? The P3 (stock configuration) has both an 0-ring groove and (one) o-ring installed into it on the piston. I was suggesting duplicating that o-ring groove by turning the piston on a lathe with the dimension(s) exactly the same as the stock groove and installing a second o-ring.


            • Brian,

              Yes, that would work, but it isn’t necessary. The one o-ring should hold the air in the gun for at least several minutes past five. You may have a small nick in the periphery of your o-ring or there may be a hole through it.

              A change should solve the problem for you.

              B.B.


  9. I just ordered the IZH-46M from Pyramyd. I was so excited until I found out that it was right hand only. I asked PA if there was someone who offered LH grips (since PA doesn’t) and she said airgunoftexas but alas they cost $180 and need 4 weeks for delivery. Not only that, but you have to buy the pistol from them, also. So, I went ahead and ordered it from PA anyway. I will either learn to shoot right handed or more likely I’ll learn how to make my own grip. Cut down a tree in my back yard and carve it up to look like the mirror image of the stock grip. How hard can it be?
    -CJr


    • CJr,

      For quite some time, Pyramyd Air has been looking for a gripmaker for LH IZH-46M grips. We haven’t been successful but continue to search in the hopes of finding a quality maker.

      Edith


      • Chuck,

        Let’s be perfectly honest. While it is relatively easy to make a pair of simple scale-type grip panels, it is quite complex to make a target grip that works properly. May have tried and failed.

        There have been left-hand grip makers for the IZHG 46 from time to time, but the demand is so low that they can’t make any money at it. So they give up. I have seen this happen many times with the IZH 46.

        The reason it doesn’t happen with grips for the top-branded ten-meter guns is the grips sell for over $200 a pair. But a budget gun like the 46 doesn’t attract buyers who are willing to pay that kind of money for just grips.

        B.B.


        • BB,
          I believe you are correct, however, those IZH-46 grips in the catalog pictures don’t look that fancy. They look like they were rough cut from a block of wood. They remind me of a Cub Scout Pine Wood Derby car. Have you seen what some of those fathers can do with that block of wood?! But your point is well taken because I have seen what my son’s cars come out looking like. Wait a minute, after we were through with them their cars came out looking like a rough cut pistol grip! I hope their mother didn’t throw them away.
          -CJr


          • Chuck,

            I’m not talking about the outside of the grips. That is simple. I’m talking about the inside that has to be sculpted to the grip frame. That is what’s complex.

            B.B.



        • Flobert,

          Maybe we should be asking you about the wood work that you want to show at Roanoke. I’ve been thinking about some grips for the 2240, a 1911A1, a Colt Woodsman Match Target and a stock for my Benjamin Discovery.

          Bruce



            • Flobert,

              Sorry my mistake. On a good day I have about three brain cells working on the same thing. Above comments were caused by having two of them on a coffee break. My comments on wood working should have been directed to Michael.

              Bruce


      • There’s a guy named Seaton Thomas [seaton2@frontiernet.net] who customizes IZH-46 grips and is said to do a fine job. He can either make a left handed grip or tell you where to get one. His fee for shaping the block that’s an Izzy RH grip into a custom grip is $125.

        If you want to spend the money, and it is a lot, Thomas Rink [formgriffe.de] in Germany will definitely make you an LH grip for the Izzy. He lists it on his site.

        pete


        • Let me add that for the cost of an Izh-46m and a fully custom grip you have a very competitive pistol for about one third the cost of one of the “world beaters.”


  10. Cowboy Star Dad,
    If you want a cool gun for the kids I recommend an IZH 60 or 61. They are safe to shoot since they separate the cocking and loading actions. They have an adjustable length of pull, good triggers, and are accurate. I would rather not get my kids hooked on semi-auto or full auto guns and I would rather they shoot pellets than BBs that will bounce around.

    David Enoch



  11. Under the heading “Magazine Lockout” shouldn’t “It’s a nice feature for a fast-firing semiauto because you won’t waste any ammo.” read, ‘you won’t waste any CO2′ ?



      • BB

        Very keen of mind are you. I own no CO2 guns, and never have, so I guess I never thought of it that way. I do own two Benjamin PCPs, so I guess that is about the same, but I merely thought of that as a limitation, compared to say springers or MPPs. But you are correct, of course, because a projectile is nothing without propulsion.

        I will say my version is more specific. C’mon BB, throw me a bone.


  12. Matt61

    I read a post of yours not long ago where you were lamenting the design of the W/E turrets on the Leapers 4-16X50, and I completely agree with you about the PIA of needing an allen wrench to adjust these turrets. Otherwise it is a fine scope, but I would never use it if I were clicking rather than holding over or using Kentucky windage.

    May I suggest the Leapers 4-16X40AO? The turrets have knurled bases that unscrew to enable W/E adjustments. The allen screw is used for resetting the zero only. I find it a much better solution than the scope with the slightly larger objective.

    I hope your feet are feeling better.


  13. I’d like to see a gun that is:

    Semi-automatic 6-10 shots
    CO2 or PCP if CO2 uses a large reservoir
    .22 caliber
    600-800fps
    Optimized for shooting fairly close-quarters at night. Ghost ring rear site post front and flashlight mount.

    Whoever makes this gun could sell a lot of ‘em to folks with possum/coon/skunk problems. These critters tend to show up at night, shots tend to be less than 10 meters but the gun’s got to have some power.


  14. Just wondering if there are any tips in storing pellets long term.
    I don’t use my pellets all at once so they can easily sit in storage for a couple of months.

    Thanks,
    Austin


  15. BB,
    Thanks for the link on the 311 yesterday — Frank had already pointed out that I asked a redundant question:), but it may save someone else asking it again. Neat little rifle. If they were going for ~$200 in 2007, I guess they are even more now.


  16. Success I think. Maybe.

    Got the new high mounts and installed them on the 97. Just the right height. Opted for a 4-16 Centerpoint like on my Talons.
    Screws are staying tight so far.
    Blasting crab apples off my tree at around 20 yds or a bit better. They are no larger than 1/2″ diameter.
    H&N FTT 4.50.
    Got a couple with H&N rifle match 4.51.

    twotalon



    • There are all kinds of crab apples. These are tiny and about all pit. Japanese crab I think. Sold as ornamentals. Loaded with pink flowers in the spring that smell a lot like lilac. Later get covered with massive quantities of tiny red apples that stay on the tree until spring unless the starlings eat them first. Calling them apples is quite a stretch. Look more like cherries.

      twotalon




      • For some reason, a different kind of crab is usually planted right beside these. They have white flowers and apples that look more like apples. Fairly small fruit, but apples for sure.

        Bet Wayne knows what they are. You see them all over the place in peoples front yards.

        I never knew how great these trees are for pulling in the starlings in the winter until I bought my house. Glad it is in the back yard where I can shoot. I can kill more starlings in a couple days than I did the whole time I was growing up.

        twotalon


        • 2talon,
          Sorry, but I don’t shoot animals. You would have a festival at my house. I have 6 pecan trees, two peach trees, two figs, 5 banana trees, purple martin house, eucalyptus tree, various bushes and evergreens in my backyard. All attracting squirrels, voles and every type of bird in the area.
          I only kill tin cans and plastic bottles

          rikib


  17. Anyone know anything about this thing I just saw on Facebook :
    Crosman is pumped about the big announcement coming on Friday!

    It was published by crosman about 6 hours ago.

    I hate teasers…

    J-F


  18. Pete,
    Thanks for the tips on grips. When I get the pistol I’ll know what to do. This thing got such great reviews I couldn’t resist even though it’s wrong handed. That’s right, I said right handed was wrong handed. I was shooting my S&W 586 tonight right handed and I can tell you it is just wrong! Really, I didn’t do too bad. Whatever I do, I need to make sure I don’t lose the right hand grips so I don’t limit my resale chances.
    -CJr


  19. BB,

    at long last, I decided to Chrony my Marauder which I fill to 2000 psi, just like my Disco. To my surprise, after 8 rounds, I’d dropped a good 30 fps. After reviewing your review where you filled your test rifle to 3,000 psi, I decided the rifle probably came adjusted for this level of HPA. The manual didn’t specify the pressure the factory adjusted this rifle to, only that it’s been adjusted to provide adequate power for hunting or target shooting. I’ve started to reduce the hammer stroke and spring tension. At one turn each, my velocity started at 867 fps, which is almost the same as with the factory setting (using an 8.85 gr pellet) and when I finally dropped down to 831 fps, I can now get to 15 rounds or so that still stay within 30 fps. An additional turn didn’t improve things much – maybe 17 pellets fired within a spread of 30 fps. This is going to take a bit more work before I can get this rifle to give me a good string with a 2,000 psi fill. For those who are going to ask why only this pressure, that’s where my aqualung is filled to. It’s a low pressure tank – max fill is 2400 and that’s when the dive shop will fill the tank to that pressure. They do tend to get a bit lazy.

    I haven’t forgotten to check the possibility that my pellets are spiraling out of the Marauder by shooting at half the range – down from 29 yards to 14 yards – to see if the three pellets in this rifle, will behave the same way – the Falcon and Air Arms shooting to the left while the Crosman Premier Heavy superdomes, hit to the right. This weekend in Jersey was kind of windy.

    Fred PRoNJ


  20. Hi I have an Mp5 K and When I shoot the gun the bbs won’t come but when i turn the gun sideways it shoots help me figure out whats wrong with this


Leave a Reply

Your email address will not be published.


9 + = 17

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>