Is this an issue? Lonex Hop Up Chamber

Discussion in 'Gun Building, Modifications & Repairs' started by Esoda, Dec 3, 2012.

  1. Esoda

    Esoda New Member

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    So today I just started putting some new parts in my G&P M4. I put in a Lonex Hop Up Chamber, Lonex Soft bucking and a madbull 6.03 black python version II.

    I had to trim down the side tabs on the hop up chamber as they were too wide to fit in the upper receiver of my M4. I got everything together finally and went out to shoot and I wasn't really seeing much of an improvement in range, but a bit of an improvement in accuracy.

    There are some strange things now that are happening with the gun. First off being when I reassemble the receiver I have to pull down with a decent amount of force for the chamber to fit against the nozzle. In return, when I remove the upper receiver now, the inner barrel and hop up chamber stay attached to the gearbox as shown in the pictures below. In order to get the chamber out I have to wiggle it around. Is this sitting too tight on the nozzle?

    Also, one thing I noticed is I am getting lower FPS. I have no chronograph to show exactly how much, but I was at an OP on Saturday and the gun shot around 415-425. It had no problem piercing the bottom of a Coca-Cola can. However now it can pierce through both sides of the can (I know that is att least 280 as my TM FAMAS could do that) but it no longer pierces the bottom of the can, but leaves a decent sized dent.

    If anyone could give me some insight if something is off here, that would be great. Thanks!
     

    Attached Files:

  2. Ehudakineyah

    Ehudakineyah New Member

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    Alrighties lol.

    For starters, why did we change out the one piece metal G&P hop chamber?

    Why are we using a soft bucking with a 420+ fps gun?

    Barrel is clean right? Is the bore 6.01mm or 6.03mm?

    Depending on the problem, you might have to use a micrometer to figure out what needs to be file'd/grinded down to match the stock hop chamber. G&P has some tight tolerances, and need to be matched by new parts that you want to install
     

  3. Esoda

    Esoda New Member

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    My hop up chamber was a lemon. It would be very loose and not move the nub at all until about the last 5 teeth on the chamber were engaged in which case it would suddenly push the nub way too far up. Took it apart and reassembled and I couldn't fix it.

    I have an M110 Spring in it, trying to bring the fps down to sub 400. When my tech put the spring in the gearbox air seal was pretty good as it was shooting around 415-430

    Yes, barrel is clean. 6.03mm TBB.

    I'll keep that in mind. I may just buy a new G&P chamber, I was recommended a Lonex chamber on the forums, I didn't know they would have compatibility issues.
     
  4. Ehudakineyah

    Ehudakineyah New Member

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    That might not necessarily make it a "lemon".

    The hop nub might just be out of spec, or... Just too small lol.
    Cut a small piece of plastic, or another hop nub about 1/4 the size of a full sized one. Glue to the face of the hop up lever and your hop up will work fine :)
    Basic McGuyver mods lol.

    Well yeah lol, brand new M110 spring and a 6.03mm barrel combo. It will settle down 390+ fps.

    Lonex Hop Chambers are alright. They are cast kinda crudely in my opinion.
    Needed to bead blast it to hell lol. Reminds me of the old Modify and Hurricane Hop Chambers lol.

    You could even use a cheap SHS metal hop ($10-15) and you would have been fine. Just gotta mod it up a bit. Shim, and install a good hop bucking :)

    If you're gonna spend a lot, the only one i recommended for the expensive stuff is a old school Systema metal hop unit lol. But... I know it's not the "best" out there now lol. Never was ;)
     
  5. Axis

    Axis New Member Supporting Member

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    This is a bit worrisome for me. I'm getting a G&P MOE Carbine for Christmas and I have a Lonex Hop Up Chamber for it...

    I wouldn't think the Lonex chamber nor the G&P body would be off-spec...This is a bit odd.

    EDIT: Okay, I did some researching and apparantly G&P externals are off-spec.
     
    Last edited: Dec 3, 2012
  6. Thestig

    Thestig Some say... Supporting Member

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    G&Ps have their own sizing system for most parts. It can be annoying at times, but in the end, the rifle can be modified to take normal airsoft or RS parts.
     
  7. Axis

    Axis New Member Supporting Member

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    I suppose if the G&P hop up chamber is metal, it doesn't really matter anyway. I can always use the Lonex chamber in another custom gun. :)
     
  8. Esoda

    Esoda New Member

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    Unfortunately the nub is not the issue, I suppose I should have been more specific on the issue of my stock Hop Up Chamber. The arm doesn't move until the last few teeth of the third gear that directly contacts the arm are engaged, and then the arm goes down until a full hop position. This could be due to the arm itself, maybe the spring that is attached to the arm or the gear that contacts it, as I said, I wasn't able to fix it.

    Thankfully M4 parts are relatively cheap. I ordered a new G&P metal hop up and will see if that solves my problem. I'm also headed to my tech today to see if he can make sense of what is going on with the Lonex chamber. All in all, having another hop up unit around isn't the worst thing in the world. I can always put it in my girlfriend's M4 if needed.
     
  9. Lil_Shady

    Lil_Shady Administrator Staff Member Lifetime Supporter

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    You might want to get rid of that Black Python too. I've used on in the past and after a few months it was garbage. The inside of the barrel is teflon coated, and over time the coating wore off. Once that happens, the accuracy goes to crap. Just some food for thought.
     
  10. Ehudakineyah

    Ehudakineyah New Member

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    oh lol, i kinda get what you're saying.

    i only meant to add a little "spacer" to the hop chamber arm. so it puts pressure against the arm and spring, so it will engage more when the hop dial is turned.

    have you taken apart the whole hop chamber yet? the wheels, arms, and all? have you noticed anything worn out or out of place?

    maybe you installed something incorrectly when assembling the lonex hop chamber? im not to sure, i would have to see it in person. But on the other hand... there is not much to go wrong here either lol

    you could even get a cheap SHS metal one piece Hop chamber for $10 lol
     
  11. Archer627

    Archer627 New Member

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    I've never had this problem with my Lonex chambers o_O.
     
  12. Ehudakineyah

    Ehudakineyah New Member

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    it happens to almost any hop chamber once in a great while :)

    no brand is perfect :)
     
  13. Archer627

    Archer627 New Member

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    I know, but I've owned a LOT of them. Lol.
     
  14. Mystery43_4

    Mystery43_4 New Member

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    SHS chambers are absolutely garbage, especially when compared to Lonex chambers which are only a few dollars more.

    As far as your chamber getting stuck to your shell when you remove your upper, there is an Oring around the portion of the Lonex chamber that enters the Gearbox shell. Remove that Oring and you won't have this issue any longer. It just provides a little more consistency.

    It sounds like your nozzle is rubbing on the ID of your chamber. This may have been caused by your slight sanding... Also make sure that your nozzle isn't bent.

    And for the last part, make sure your HU assembly and Bucking is installed correctly...
     
  15. Ehudakineyah

    Ehudakineyah New Member

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    Lol I know they're garbage xD haha. But they're great last minute dirt cheap replacements lol. But better then a lot of stock crappy hop chambers.

    They're decent when shimmed, and provided with a good hop bucking lol

    And SHS is a lot easier to order bulk from lol.
     
  16. Esoda

    Esoda New Member

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    Well went out to my tech today and got it figured out.

    Gun was shooting consistently at 300 fps, so it had lost about 100 fps.

    G&P has very tight specifications for their chambers, as we were looking at the chamber the tabs on the side seemed to be good, but the depth of the little ring on the back of the chamber that sits against the nozzle was off compared to the G&P chamber as well as a couple other chambers we looked it. Further inspection revealed and air seal issue with the depth in which the chamber was sitting against the nozzle.

    To get the Lonex to fit in that G&P body it would take a lot of grinding and modifying, but he showed me what is likely wrong with my chamber (I was smart enough to not bring it...) and I will attempt fixing it. If not, I ordered a new G&P chamber anyway, as they are cheap and I can always put it in my girlfriend's M4, and it never hurts to have spare part. Plus it comes with a bucking so I can practice flat hopping!
     
  17. Mystery43_4

    Mystery43_4 New Member

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    The issue with your G&P chamber is between the hop up arm, and the cam.

    Replace the arm and cam with the Lonex ones and you should be fine, or replace all of the gears of you'd like.