The Beeman P1 air pistol: Part 7

by Tom Gaylord
Writing as B.B. Pelletier

Part 1
Part 2
Part 3
Part 4
Part 5
Part 6

Beeman P1
Beeman P1 air pistol.

This report covers:

  • The test
  • RWS Hobby
  • RWS R10 Match Pistol
  • Sig Match Ballistic Alloy
  • Crosman Premier light pellets
  • Discussion
  • What comes next?

Today we look at the velocity of the new/old Beeman P1 pistol I tuned for you. If you recall, I wanted to get a few shots on the powerplant first because the pistol acted like it had just been tuned. I got 40+ shots in the accuracy test in Part 6, and, while that isn’t a real break-in, it’s at least a start. Let’s get right to it because I have other things to talk about.

The test

I decided to test the pistol with the same three pellets I used in the first velocity test. That was reported in Part 2. That will give us a direct before/after comparison. I also added the Crosman Premier 7.9-grain pellets that showed so much potential in the last accuracy test. They weren’t in the first velocity test. I’m not testing RWS Superdomes, but you should get a sense of where they fit in when you see what the other pellets did. This is a test of the tuned powerplant — not a test of each and every pellet.

RWS Hobby

First to be tested was the RWS Hobby . Let me show you what I got before and after the lube tune.

Before…………………..After
Hi…..Lo………………..Hi…..Lo
541…423……….……436…336

The spread on high power was 24 f.p.s. — from 420 to 444 f.p.s. On low power the spread was 38 f.p.s — from 310 to 348 f.p.s. The gun lost about 100 f.p.s. with Hobby pellets. If that continues, and I bet it will, I will have a lot to say.

RWS R10 Match Pistol

Next up were the RWS R10 Match Pistol pellets. These were the speed demons of all the lead pellets in the first velocity test. Let’s see how they compare before and after the lube tune.

Before…………………..After
Hi…..Lo………………..Hi…..Lo
578…457……….……474…382

The high velocity spread was 7 f.p.s. — from 470 to 477 f.p.s. On low power the spread was 14 f.p.s. — from 374 to 388 f.p.s. We see pretty much the same results with this pellet. The P1 has lost a lot of power!

Sig Match Ballistic Alloy

The Sig Match Ballistic Alloy pellet was the absolute fastest pellet in the before test. At 5.2 grains you would expect it to be. Let’s see where it is now.

Before…………………..After
Hi…..Lo………………..Hi…..Lo
649…478………….…469…328

How about that? The fastest, lightest pellet also lost the most velocity from the lube tune. The spread on high power was 25 f.p.s. — from 455 to 480 f.p.s. On low power the spread was 86 f.p.s. — from 279 to 365 f.p.s. I think that large spread indicates something special may be happening with this pellet on low power. Perhaps its skirt isn’t getting blown into the bore enough to seal the barrel and air is blowing past?

Crosman Premier light pellets

The final pellet I tested was the Crosman Premier 7.9-grain pellet that was so potentially accurate. I don’t have numbers for before the tune — just after. Let’s see how it did.

Before…………………..After
Hi…..Lo………………..Hi…..Lo
NA…NA………………393…291

The spread on high power was 16 f.p.s. — from 384 to 400 f.p.s. On low power it was 23 f.p.s. — from 283 to 306 f.p.s.

Discussion

These results are unacceptable to me. Too much power has been lost. Two things stand out to me from these results. The first is the Beeman P1 pistol powerplant is extremely sensitive to the use of Tune in a Tube (TIAT) grease. And the second is the fact that I used too much of the grease when I tuned the pistol. I treated it like a spring piston air rifle

I mentioned that my other Beeman P1 is not that harsh when it fires. This one wasn’t, either, but I wanted to try the TIAT to find out how well it works. I found out a lot more than I expected to.

Here is what I think I have learned. Tune in a Tube grease can be used on the mainsprings of rifles and they won’t lose very much power/velocity. But a high-performance spring pistol like the P1 is doing so much with a very small mainspring! I think TIAT can be used, but just sparingly. It isn’t required for vibration damping — just for lubrication.

What comes next?

Well, I was all set to tell you about a special accuracy test I was going to conduct next, where I sort pellets with the PelletGage and do some other things you readers have suggested. I think that has to wait until I retune the pistol. I love the way it shoots right now but I’m unwilling to give up that much power when I know it’s there.

I don’t know yet what I’m going to do in this next tune, but I may change all the parts — mainspring, piston seal and breech seal — for the new ones I have. Then I will lubricate the pistol again, and go light on the TIAT. That will be followed by another of these velocity tests.

You readers have a big influence on me, so please talk amongst yourselves. I will observe.

44 thoughts on “The Beeman P1 air pistol: Part 7


  1. B.B.,

    If you are going to open it up again I would suggest that you scrag the new spring and use a drill press for the reassembly. I counted the coils of the old and the new and came up with the same number. I agree with Gunfun1 that TIAT is the main culprit of the power loss. My reasoning is that the components are so tightly fitted inside that you don’t need the anti-vibration property of TIAT. The stickiness of the substance is retarding the movement of the parts. Maybe just a light application of synthetic oil as Duskwight described so long ago /blog/2012/02/how-to-lubricate-your-spring-piston-airgun/

    I wonder how Duskwight is doing with his Duscombe project?

    Siraniko

    PS: Section Discussion Third Paragraph second sentence: “Tune in a Tube grease can be used on the mainsprings of rifles and they won’t loose (lose) very much power/velocity.”


    • Siraniko
      I don’t know if tune in a tube is the cause.

      But that would be the only way to know is not change anything else in the gun. And only remove the excess tune in a tube.

      If other componants are changed along with reducing the amount of tune in a tube you will not know what was the cause of the slower velocity.



      • GF1,

        I will second your suggestion of lithium grease in this application.

        I also have a can of “Moly-Slip” (a Canadian company) molly grease that has about the same light creamy consistency as lithium that has been my go-to for decades.

        Typically use the molly for internal applications (springs and such) and the lithium for external ones like pivot points.

        Hank


        • Hank
          I use the white Lithium grease inside all my air guns. Pcp or springers and even multi pumps. Even inside Co2 guns as well as tryed it on Co2 cartridges on the head of the cartridge.

          But that did help bring the velocity up on my FWB 300 and worked the same way as well on the .177 and .22 Tx 200’s.

          And definitely works good on trigger componants. Matter of fact that’s what went inside the WildFire when I modded it.

          Definitely hooked on using the white lithium grease.


    • I too often wonder about Duskwight and the Duscombe. For those not familiar, a fellow was/is building an opposing spring piston rifle from the ground up,… every piece. Not sure, but maybe the trigger components, barrel and springs might be the only things not hand made. Jaw dropping stuff.

      Perhaps B.B. could reach out if he has any contact info. OR someone could find an old Duskwight post and send a new message.



  2. B.B.,

    Wow. I do not think that anyone saw that (severe fps % loss) coming. We have all learned something. I think that we all will be patiently to see how things turn out. Normally, breech seal, piston seal and spring issues would be suspect, but I think in this case that those items can be safely ruled out.

    Good Day to you and to all,…. Chris



      • GF1,

        Well, we will all find out together. My gut says a breech seal or piston seal issue. The drop in fps just seems to severe to attribute to just grease. The piston seal was cleaned, but sometimes cleaning an old part can be bad. Tear apart and clean an old style set of valve lifters and they will “clack” like nobody’s business. The varnish was acting as a seal to make up for wear. I am not saying that is the case, but something to keep in mind depending on what one is working on.

        I do not even think it is possible, but could enough grease cause a suction effect and be pulling back on the piston as it is trying to move forward? Not likely, but a thought.


        • Chris
          Who knows. There could be suction I suppose. I imagine if the spring giude and inner piston where the spring rides is a close tolerance like when you put tune kits in. Maybe that could cause a suction if too much grease is there.

          Like you say. We will find out. Will be interesting to see what the problem is.


  3. BB,

    I am with GF1. I think you should first remove some of the TIAT and check the velocity results before replacing any parts. That will be a good demonstration of proper lubrication and how the amount of lubrication can directly affect performance in a sproinger.


  4. BB

    May be something going on other than TIAT. You had to fight the mainsprings, first the new unscragged one and then the old. Binding parts? I echo Gunfun’s comments about just removing some TIAT only. But how many more times are you wanting to tear into this complex pistol?

    Decksniper


  5. Hmmm…I’d have to concur with removing the Tune in a Tube and just very lightly re-treating, or using a lighter lubricant altogether. I generally lean toward “If it ain’t broke, don’t fix it.”


    • Hey HiveSeeker,

      I TRY to follow the “if it ain’t broke, don’t fix it” rule but often succumb to the “curiosity killed the cat but satisfaction brought it back” corollary.

      Can’t seem to resist disassembling things to polish and tweak them.

      Working with engineers for 45 years seems to bring out the “I can improve this” tendency in people. 🙂

      Hank



      • Hi Vana2,

        I hear ya. I work on computers as a hobby and have managed to break stuff that was not broke trying to tweak and improve it. Microsoft teaches some hard lessons.

        And while we’re on the topic, I keep hearing this definition bandied about that insanity is doing the same thing over and over but expecting a different result. Whoever came up with that never owned a Windows PC.


        • Hi HiveSeeker,

          Know what you mean about computers – been using them for 30 +years (started out on VAX systems) and taught IT at the college level for a couple of years. Not surprisingly, now that I am retired I prefer my interaction with the hardware and software to be as a casual user 🙂

          I do have a kick-ass workstation capable of running CAD,CAM and Flight Simulators but have deliberately avoided getting into the over-clocking scene. Had enough of that.

          Like your definition: “Insanity – doing the same thing over and over and expecting a different result”.

          The quote I use (I was a designer by trade) is: “You can’t expect to solve a problem by using the same thinking that created the problem in the first place”

          I made up a plaque with that saying and used to keep it on my desk so I could point to it when needed. One of the engineers asked to have that plaque when I retired, gave it to him. LOL!

          Hank


          • Hank,

            So — you worked with the boys out on Route 128?

            Here’s a bit of trivia for you. The first Star Wars movie — Episode 4 — the three paragraphs of opening words that move up screen and get smaller until they disappear were rendered by a VAX 11-780! That’s how much computing power that graphic animation required.

            B.B.


            • LOL! B.B.!

              I remember being so Impressed with the VAX – a $650,000 machine; 1 MIP (1,000,000 instructions per second) with 8 MEG of memory. Needed and air-conditioned environment, special powersupply and an operator in constant attendance to keep an eye on it.

              In this day and age, the VAX is about as powerful as a $5 solar powered calculator LOL!

              We had about 25 VAXes in the company all named after characters in the Lord of the Rings. I worked on Gandalf.

              Interesting that you mention Starwars – I watched Episode 1 last night with my granddaughter and we will be watching the whole series over the next couple of weeks.

              Hank


          • Vana2,

            Yes, like you I don’t work on computers as much as I used to though I was never at your level! Despite being fairly “techy”, I must confess to being slow to upgrade when my computer is doing what I need it to. I got over a decade out of Windows XP but lack of browser support finally forced me to upgrade. My wife is a Mac person and she just chuckles when she sees the trials and tribulations occurring in my half of the office!


  6. Hello B.B. et all,
    Some thoughts came to mind that may help. I also have a P1, a couple of P17’s, and Webley/Zoracki Alecto. All of these hinge at the front, and the barrel pivots up and away during cocking, breaking and making contact with the fixed breech oring. The slightest loss of sealing pressure or debris, or cut on this oring will cause a loss of air.

    Also, if you remove and reinstall the barrel on these guys, for cleaning, crown/breech polishing for instance, you have to take care to restore it’s linear position in the barrel clamps to produce the right contact pressure with the breech oring when you close the upper receiver after cocking.

    I guess the Teflon piston head is self lubricating in this pistol. If you put any TIAT on it, or if any has flung off of the spring, it may actually cause extra drag compared to dry Teflon.

    Good luck, I look forward to the next report. We all learn together when you perform these tune-ups and write about them!


    • Feinwerk
      Very good info.

      I don’t have one of these pistols. But can that sliding of the barrel be done easily?

      And I guess the only way to test is shoot over a chrony and see if the velocity rises or falls after the barrel adjustment?

      Maybe BB should just try that first if it’s easily done. That way he won’t have to disassemble the gun again.

      Then if it works and raises the velocity we will know it wasn’t tune in a tube. The more I write the more I’m convincing myself that you may be right.


      • Hello Gunfun,
        Yes it’s pretty easy, there are two clamps, one on each end of the barrel, and each clamp has two screws. I think the barrel on the P1 has a groove for the clamp bar but there is a small amount of linear adjustment. I would first check the O-ring to see if it is still in place, or has a cut, or a lead flake from a pellet for instance or something stuck to its face preventing good sealing. I don’t recall BB saying that he removed the barrel so that spacing should still be intact.

        I placed a small dab of dielectric spark plug boot grease in a spot inside the frame so that I can put my finger in there and pick up a tiny amount from time to time to wipe on the face of the breech o-ring.

        Another thing that can happen is that a sharp edge on the barrel can gouge out a chunk of this o-ring when the upper receiver closes. This is probably not the case but it is something to check for.

        After I bought my P1, I found a supplier and purchased a 22 caliber and a 20 caliber Barrel, as these are easily interchangeable. But I have never used the other barrels and just stayed with the 177.

        I removed the barrel and chucked the breech end into a hand drill and used the corner of a cratex polishing block with a drop of oil to polish the crown. I turned it around and also polished the breech entry and also the outside breech-end corner to be sure that it had sufficient radius to not cut the breech o-ring.

        BTW, cratex polishing blocks are kind of like small erasers with various sizes of grit embedded into them.



        • Feinwerk
          Sounds pretty simple on the barrel adjustment.

          And yes the Craytex polishing stones we call them at work. And yes I know they are flexible and not really stone. Just a term we use. But have used them for years. They work great for polishing and deburring.


        • Feinwerk
          I too purchased both the .20, and .22 cal barrels for my 2 HW45 air pistols. When I swapped the .177 barrel for the .20, and .22 cal barrels, I noticed there is a notch cut into the barrel that aligns perfectly with the rectangular barrel retaining plate. And once the barrel is fitted into the gun, and the retaining plate fitted into the barrel notch, there is no room for evan minor barrel adjustments without having to do some machining. I have kept an eye on the barrel o-rings, and have not noticed any significant wear evan after 3 years. BB’s “after” chrono results with 7gr Hobbies, are almost identical to the 447 fps I’m averaging with .20 cal, 10.96gr Beeman Silver Sting pellets. They aren’t available anymore, so it’s a good thing I stocked up on them, and a variety of Beeman .20 cal pellets while they were still in stock.
          This is why I enjoy working on Weihrauch, and other fine German, and English airguns. All the parts are made to fit perfectly. It’s Teutonic precision at it’s finest.
          Oh yes, I believe Duskwhite finished his massive airgun project a few years ago, and wrote it up in one or two guest blogs as well. It should be archived.
          Ciao
          Titus


          • Titus,

            The last I remember of the “Duscombe” was a bunch of shots of intricately machined parts. I remember nothing of a finished product. It would be very nice to have an update. I might look a bit this weekend, but not sure how to start a search. I usually have good luck searching the blog, but am not sure how I would search that one.

            I do remember, I think, that a lot of consideration was given to weight reduction by “swiss cheesing” the metal parts. That seems to stick in my memory.



  7. Chris USA,

    The last entry I could find of the Duskcombe is here: /blog/2012/12/how-hard-is-it-to-make-a-good-springer/

    He had already made the prototype fire at 12fpe. I just don’t know how he is getting along with the Mk2 which would be lighter I think.

    Siraniko


    • Siraniko,

      I did the RSS thing. I saw you comment and clicked on one of the 2 links and sent Duskwight a request to give us all an update. (Thank you for your assistance.) 10/2014 seems about right, but I swore that it was around 1 year to 1 1/2 years ago. I do remember the pictures. I think that he never did a guest blog but rather just really nice info. and photo updates in the comment section from time to time as his project progressed.

      Chris


      • Chris
        You’re probably correct, as I have failed to find any blogs written by Duskwhite describing his project. What I do remember, is that it was based on BB’s iconic, full size Whistcombe double spring piston air rifle that produces almost zero recoil. However, Duskwhite made his in a bullpup configuration, and was disappointed by how much his finished air rifle weighed. I believe he made a laminated stock for it as well as using a Lothar Walther barrel, but the overall length, twist, calibre, and number of lands and grooves escapes me. Anything more info would be just speculation on my part. Thank you for sending him an inquiry concerning the modifications he made to his second attempt.
        I do miss Duskwhite’s excellent, and knowledgable comments, and hope your inquiry finds him in good health, and spirit.
        Ciao
        Titus


  8. To All,

    To search the entire blog for a particular comment is daunting. It can be done however, if you know what or who you are looking for. Using the search function of Google enter the term/s and/or name/s you are looking for. You may even as the year to further narrow your search then after entering your search string add the site you are searching in this case pyramydair.com/blog comment. Press enter and you should be able to get a series of possible pages you are looking for. In this case I entered: Duskombe pyramydair.com/blog comment

    Siraniko


    • Hi B.B.,

      If I’m spending that much money, I shouldn’t have to do any real tampering. All of those issues should have been done by the R&D people. Isn’t that why I’m paying all that money?

      Id’e like to see you remove ALL the TAIT and use some high quality lube designed specifically for that purpose. Something like RWS spring cylinder oil.

      Here’s my thinking…When we use the words “harmonics and tune” we are talking about properties that exist in nature. The very properties that man has harnessed to create music. Therefore, a high quality spring pistol or rifle should ring like a high quality musical instrument. It’s on us to learn to play it well.

      Don’t get me wrong, I like hot rods too. But they are usually made out of Ford’s or Chevy’s rather than lamborghini’s.

      What I’m saying is this… If you need to tune a TX200 then Air Arms aint doin sometin right. 🙂

      Tnx, John

      P.S. Didn’t they use to make a stock for the P1? But then why not just buy a rifle instead? BTW I am very much enjoying this series and I hope you eventually get that new spring fitted. But I’m against dampening the harmonics for now.


  9. John
    I like that.

    “Here’s my thinking…When we use the words “harmonics and tune” we are talking about properties that exist in nature. The very properties that man has harnessed to create music. Therefore, a high quality spring pistol or rifle should ring like a high quality musical instrument. It’s on us to learn to play it well.”

    And to tell you the truth the ring don’t bother me. I like my lube light actually. But I do want my springers to be smooth. And there is definitely other ways to do it than gooping them up.


  10. Thank you Gunfun1!

    I imagine it would take a lot of time and money to make a springer with all the parts vibrating in harmonic resonance. It might be theoretically possible though. Now if I could just get Thomas Edison on the phone… 🙂

    I think PCP’s are where all the research dollars are going these days.

    I wonder if anyone has ever made a springer with a spring that worked in tension rather then compression?

    John


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