The Javelin M24 Project - Part 2

Continuing with my Javelin M24 project, I placed an order with one of my local airsoft shops in North Tonawanda NY for the cylinder internals. While the shipment took forever and a day, at no fault of Ready4Chaos mind you, I decided to work on the accuracy portion of the M24; the hop up and inner barrel. While this sounds super easy, trust me when I say it was beastly.

The inner barrel I am using, the Madbull Black Python Inner Barrel – 6.03mm diameter, 509mm length, was about 30mm longer than the stock barrel. This meant that I would have a tiny bit of inner barrel sticking out the end of the outer barrel. To cover this up, I sourced the Falcon Snow Wolf M24 Silencer Adapter and a 40mm x 200mm Spartan Doctrine Lightweight Mock Silencer. 200mm is a bit long and a I may replace this in the future with something a little slimmer/shorter, but for now, it looks mean. The original barrel cap was a beast to get off, requiring Herculean strength and a heat gun as there was an overabundance of glue on the threads when the factory sealed it. Once off, there was a lip on the silencer adapter that would not let the inner barrel pass through. Chris worked his magic with tiny files (and the patience of a monk) to remove the lip, letting the inner slide through. With the PDI Snow Wolf M24 Hop Up Chamber installed, Chris noticed the inner barrel wobbling around the end of the silencer adapter and had the genius idea to a a very small, thin o-ring to act as a barrel spacer. The inner barrel is rock solid with not a bit of movement. Big thanks to Chris for his help on the external components, I don’t know if I would have been able to get all that installed without his efforts.

Once the parts order arrived, we moved onto the cylinder upgrades. The stock upgrades weren’t horrible or broken. They were very clean and lightly oiled but not putting out the FPS I needed to be competitive on the field. I decided to do a complete swap of the internals at one go rather than piece it out, here’s what I dropped in:

King Arms Reinforced Piston for APS-2
Guarder Precision Piston Head for APS-2
Angel Custom APS-2 Ball Bearing Spring Guide (7mm and 9mm)
Angel Custom SP150 Spring

The install was pretty straight forward with no additional modding whatsoever. I greased the new piston head and that was pretty much about it. I did wrap Teflon tape around the cylinder head before screwing back on to the cylinder, but who doesn’t do that to spring rifles? Once reassembled, it was off to the chrono. Using Tsunami .20g bbs, I was shooting at a high of 543 FPS and a low of 538. Just a little too hot for the local fields but I can drop that with a spring mod or two. That can be round 3 of the modifications. I haven’t done any range testing yet and I don’t have my heavy-weight bbs in. With a target FPS of 500 w/.20g bbs, I’m planning on using .40s, maybe .43s but further testing will determine that.

All in all, she’s coming along nicely and I’m still on track to have her fully functional by the end of April.

Radar

December 23, 2019

Comments (2)

James

December 23, 2019

To whom it may concern, put of curiosity I have a javelin m24 with a scope and it slam fires. The hop up is ferociously retarded and I want to do the pro drop in. I however do not want to do the suppressor stuff you mentioned earlier. In addition, I want to keep the stock spring and just replace the spring guide and piston. I’d like to cushion the force of the piston against the piston head in order to reduce noise and increase longevity of piston head.

I need to know what type of barrel to get.. tryna not go overboard. Just something accurate that fits, that works, and what hop up bucking would you recomend?
- Radar
  
  December 23, 2019
  
  Hey James,
  
  Thanks for stopping by and leaving a comment. Your slam-firing sounds like a worn sear, if you need a replacement, here’s an Evike search that has a few options for you. I agree that the stock hop-up unit is atrocious.. I have nothing nice to say about it but kudos to you for sticking it out this long! Good idea on cushioning the cylinder head, you shouldn’t need too thick of a pad to get the job done.
  
  The PDI hop-up replacement is super sweet and can take practically any AEG inner barrel you can throw at it. As for recommendations, I would stick with 6.03mm diameter (the debate over 6.01 vs 6.03 is real) and for length.. I would go with the 509 and just cut, file and crown the barrel to the length you want. I like Madbull and Prometheus brands but that’s just because the era I started playing in and I’m stubborn when I find something I like.
  
  The silencer adapter serves a 2 functions as it provides stabilization in the outer barrel and hides the majority of the extra length of the 509. I don’t attach the can itself unless I’m just showing it off as it’s just too damn long for in-game use and provides no value. I did add a thread protector to the adapter after a few nose-in-the-dirt experiences.
  
  Buckings compatible with the PDI hop-up and AEG inner-barrel are, “shockingly” AEG as well, I haven’t replaced mine in ages but I like the performance I get from the G&G Green bucking. I feel like hop-up buckings are personal preference like socks or underwear and the only way to know if you love it is to try it out for a few games.
  
  Hope that helps. Happy hunting.
  
  – Radar