Reduced action noise in my impact

Forums PCP Airguns Reduced action noise in my impact

  • Views : 424
  • Link

    bucketboy
    Participant
    Member

    While this might not be much of a concern to you guys who shoot high power, the action noise on my impact drives me nuts. The floating a hammer  spring guide,  the rattle of the hammer inside the block and as the hammers wobbles about on the valve stem makes the gun feel and sound (sorry for this FX) both  cheap and nasty. The gun is not loud but compared to the noise (or should I say lack of it) of my other guns, the impact sounds like a tool box full of spanners.

     

    So, last night I took the gun apart and had a look to see if I could make improvements? The first thing i noticed was how loose the spring guide was inside the spring, how loose was the spring inside the hammer and the bore of the hammer was 4mm while the valve stem is only 3mm. All of these cause rattles.  After a bit of measuring I realised I could turn up some new PTFE parts that were not only made to tight tolerances but they would effectively stop all unnecessary metal to metal contact.

    I replaced the delrin floating spring guide with one made from ptfe, which is slightly heavier, much less friction and softer so even if it does rattle it’s not as loud.

    I also made a top hat for either end of the spring that holds it 100% central to the valve stem so the hammer moves exactly the same each time. The guide (right) pushes into the hammer reducing the bore from 4mm down to 3.2mm, the hammer now slides slicker than snot with almost no wobble.


     

     

    I also made a sleeve to fit inside the valve return spring (uk spec) again to reduce slope and metal to metal contact.

     

    so, this morning I set it up and WOW, the difference is huge! Not only soooooo much quieter, less vibration and more consistent over the chrono.

    Its still not as quiet as my quietest gun but it is not far behind…….well pleased  it now feels like the gun it should be πŸ˜€ 

    Bb

    • This topic was modified 2 months ago by bucketboy.
    Link

    sonny
    Participant
    Member

    Very nice. I'm always amazed with the innovation and talent of people on this form +1 to you sir.

    Link

    Acruz
    Participant
    Member

    Outstanding. If I had half your brain I'd be dangerous..

    Link

    knifemaker
    Participant
    Member

    A little ingenuity can sure go a long way. Well Done! :<)

     

    Knife

    • This reply was modified 2 months ago by knifemaker.
    Link

    stoti
    Participant
    Member

    That's cool BB. I just got done installing all the power mods on my new Impact and tuning it over the past couple of weeks. I installed a different hammer and spring guide for one end of the rod but nothing on the other end. That's a great idea. I have something similar in one of my AR's, it's a captured buffer tube spring so you never hear the buffer spring grinding on the buffer tube. Great thinking! I wish you would have made about 20 of those things, I would have bought one! Have a great day!

    Stoti

    • This reply was modified 2 months ago by stoti.
    Link

    Airgun-hobbyist
    Participant
    Member

    Another great innovation from Bb!  As Stoti indicated, you should be able to sell quite a few sets of these.

    Link

    lenweber2
    Participant
    Member

    You guy's can hear all this?   LOL Nice work.

    Link

    mubhaur
    Participant
    Member

    Very nice  Bb.

    Regards, 

    Umair Bhaur 

    Link

    bucketboy
    Participant
    Member

    lenweber2

    You guy's can hear all this?   LOL Nice work.

    These simple little modifications reduces the block noise from 96.8dB down to 88dB.

    I need to fit a digital gauge , seriously I can hear the needle vibrate in the original, 😊 

     

    still some way to go, my quietest gun is a mere 73dB

     

    Bb

     

    Link

    nomojo65
    Participant
    Member

    Looks good! Nice ideaπŸ‘πŸ» If you do decide to manufacture I’m sure you’ll recoup your costs!

    Link

    bucketboy
    Participant
    Member

    Thanks guys, the parts aren’t difficult to make but the uk spec guns and us spec are different. Different valve stem, different hammer, different hammer spring and without access to those I can’t make the parts to the tolerances I would be happy with.

    To be honest, because you guys shoot at  higher power, any action noise is drowned out by the muzzle report. With our restrictions, the gun is not working very hard at all but the block was louder than I am used to, part of that though is the fact that it is a bullpup ,so the action is a lot closer to my ear.

    I know the fx impact has a huge fan base particularly with those who shoot high power or shoot slugs and I can understand why. I really like mine (I am going to feel like a traitor now) but there is nothing it can do that my other guns can’t do as well or better. 
     

    Bb

    • This reply was modified 2 months ago by bucketboy.
    Link

    bubblerboy64
    Participant
    Member

    bucketboy

    Thanks guys, the parts aren’t difficult to make but the uk spec guns and us spec are different. Different valve stem, different hammer, different hammer spring and without access to those I can’t make the parts to the tolerances I would be happy with.

    To be honest, because you guys shoot at  higher power, any action noise is drowned out by the muzzle report. With our restrictions, the gun is not working very hard at all but the block was louder than I am used to, part of that though is the fact that it is a bullpup ,so the action is a lot closer to my ear.

    I know the fx impact has a huge fan base particularly with those who shoot high power or shoot slugs and I can understand why. I really like mine (I am going to feel like a traitor now) but there is nothing it can do that my other guns can’t do as well or better. 
     

    Bb

    I agree if you are not shooting at long range or it high power the impact is not the gun.  Here in the US we’re shooting air rifles beyond 100 yards and at high FT LBS    The impact makes some sense then Some not a lot πŸ˜€πŸ˜€πŸ˜€ 

    Frankly the only real advantage I see to the impact is what you can do with it as far as modifications.  It’s not a good first gun or maybe even second gun . 

    Link

    Vana2
    Participant
    Member

    bucketboy

    Thanks guys, the parts aren’t difficult to make but the uk spec guns and us spec are different. Different valve stem, different hammer, different hammer spring and without access to those I can’t make the parts to the tolerances I would be happy with.

    To be honest, because you guys shoot at  higher power, any action noise is drowned out by the muzzle report. With our restrictions, the gun is not working very hard at all but the block was louder than I am used to, part of that though is the fact that it is a bullpup ,so the action is a lot closer to my ear.

    I know the fx impact has a huge fan base particularly with those who shoot high power or shoot slugs and I can understand why. I really like mine (I am going to feel like a traitor now) but there is nothing it can do that my other guns can’t do as well or better. 
     

    Bb

    Excellent post Bb! 

    In Canada any type of silencer or moderator is illegal and I expect (don't have mine yet) that at full power it will be quite loud and mask any internal noise. Still, anything that reduces friction and tightens tolerances might be a good thing. Being a compulsive tinkerer I will probably make up a couple of these and try them out.

    Your comment: "there is nothing it can do that my other guns can’t do as well or better"  …seen you post that before.  I am thinking that being designed to operate at a much higher power, that at 12 fpe the Impact is at a disadvantage and things like noisy springs become noticable. Kind of like an 8 cylinder engine with 4 spark plugs removed would not compete well with a proper 4 cylinder engine? If the tables were turned and all your rifles were (theoretically) tuned to 35-45 fpe that would suit the Impact, do you think that you might view the capabilities of your Impact differently? I am just curious as, until I have my Impact I can only speculate as to how it fits, performance wise, with the rest of my AGs.

    ATB,  Hank

     

     

    Link

    bucketboy
    Participant
    Member

    Vana

    Excellent post Bb! 

    In Canada any type of silencer or moderator is illegal and I expect (don't have mine yet) that at full power it will be quite loud and mask any internal noise. Still, anything that reduces friction and tightens tolerances might be a good thing. Being a compulsive tinkerer I will probably make up a couple of these and try them out.

    Your comment: "there is nothing it can do that my other guns can’t do as well or better"  …seen you post that before.  I am thinking that being designed to operate at a much higher power, that at 12 fpe the Impact is at a disadvantage and things like noisy springs become noticable. Kind of like an 8 cylinder engine with 4 spark plugs removed would not compete well with a proper 4 cylinder engine? If the tables were turned and all your rifles were (theoretically) tuned to 35-45 fpe that would suit the Impact, do you think that you might view the capabilities of your Impact differently? I am just curious as, until I have my Impact I can only speculate as to how it fits, performance wise, with the rest of my AGs.

    ATB,  Hank

     

     

    Good question, the main advantages an impact has are, long barrel in a compact design, relatively light in weight and the huge plenum means you can get good power without high reg pressure so hammer load is less.

    I would guess that fx have spent little or no effort trying to make an impact work really well in sub 12 power level, so yes I would expect it to be better at higher power.

    It is not really a fair comparison between my other guns (all Theoben rapids) because I have had them for years and heavily modified them all, almost nothing inside is standard, I have ,tried many different barrels and pellets until I was finally happy with them,. A thousand little things make no difference on there own but added together there is a big improvement. 2 of my guns are crazy accurate, 2 are insanely quiet all will have extreme spread better than the standard deviation on my impact so the impact has no chance.

     

    I have in the past held a fire arms license, when testing I manage to get a 14.3 gn .20 prem to 1476fps, I have also had a 9mm 81 gn jsb doing 165fpe so speed and power are not an issues with them. 
    I also make my own sound moderators,, so regardless of power I think my rapids would still have a an edge over an off the shelf impact.

     

    The one gun I would swap my rapids and impact for is one I can’t get, that would be based on a RAW 1000x block (basically a rapid with a lever ), the uk importers wont order me a block, Airforce won’t reply to emails. So if anyone has a hm1000x block for sale,let me know..

     

     

    I am sure you will like the impact but it will be a cannon without a mod 😧 

    Bb

     

    Link

    Vana2
    Participant
    Member

    @bucketboy

    Thanks for the reply!

    I'm not overly concerned about the discharge report as I have my own shooting range on 10 acres in a rural area where there are no restrictions on what I shoot. I am respectful of the neighbors though and don't shoot powder burners when it might disturb them. πŸ™‚

    I will be extending my 50 meter shooting range across a portion of the beaver pond and now that it is frozen over I have had a chance to (roughly) pace off the distance – I should be good for at least 125 yards from the bench. Happy with that!

    I will be leaving my Impact in factory configuration until I have broken it in and become comfortable with it (this will be my first bullpup gun). After I have a good baseline I plan on doing the TP and probe mods and see where that puts me for liget slugs. I am not into extreme range shooting (yet – LOL!).

    I have a friend in the US who is fond of his RAW 1000x, I will make inquiries if he can get a block. If yes, I will get him to PM you.

    Hank

Viewing 15 posts - 1 through 15 (of 15 total)

You must be logged in to reply to this topic.