bean Posted July 11, 2011 Report Share Posted July 11, 2011 The little spring attached to the valve knocker on my gun seems to have possibly ate it. I say this because its always forward and the hammer hits it but cant make the mag release gas. Has anyone else had this issue? The bolt also sometimes get hung up there so I am assume the spring is pushing on the bolt catch pushing it up into the bolt as it attempts to slide forward. Quote Link to post Share on other sites
slipknot1971 Posted July 11, 2011 Report Share Posted July 11, 2011 Hi Guys! I have a question for you all. My M4 will not fire in full auto mode. It fire's perfect-ally on semi auto with no issues. Â What it does is fire 1 round as if it is in semi and the trigger fails to re-set. Any Advice? Anything need to be clarified? Any help would be greatly appreciated! Â Â Try blowing some air...it's possible that something is jamming the movement of the safe-fire selector...it's my guess.. Quote Link to post Share on other sites
trustkill Posted July 11, 2011 Report Share Posted July 11, 2011 Thanks for the suggestion Slipknot, I will give it a shot and see what happens. Quote Link to post Share on other sites
fadz Posted July 15, 2011 Report Share Posted July 15, 2011 I just got the new version bolt of the KJ M4 in Taiwan. Bringing it home today and will test the performance over the weekend.  Here is a first look guys, please check it out. I want to install upgrades especially the Cradle Velocity Reducer. RA Tech told me their upgrades are compatible. T_hum, hope you can help...  1. Underside View:  2. The single moving part (piston) extended  3. Closer View of the rear of the piston...notice that the piston ring is facing rearward...  4. View of side... There is a screw in the ribbed part...I have no idea yet how to safely take this apart...any suggestions:  5. Front View Quote Link to post Share on other sites
t_hum Posted July 16, 2011 Report Share Posted July 16, 2011 My initial guess is that they haven't changed the valve which means the reducer would work. The piston is obviously not compatible but perhaps their urethane deals will work in this application. Without inspecting the mechanism it's hard to say. I'm most worried about prematurely wearing of the bolt catch surface. Every other system that uses this style carrier arrangement suffers in this area. The steel pin through the plastic bolt cup was a great design move by TK its a shame they ditched it. Quote Link to post Share on other sites
PanteraTigris Posted July 16, 2011 Report Share Posted July 16, 2011 Lucky for me i have a spare bolt and nozzle. Quote Link to post Share on other sites
DiscoBiscuit Posted July 16, 2011 Report Share Posted July 16, 2011 My initial guess is that they haven't changed the valve which means the reducer would work. The piston is obviously not compatible but perhaps their urethane deals will work in this application. Without inspecting the mechanism it's hard to say. I'm most worried about prematurely wearing of the bolt catch surface. Every other system that uses this style carrier arrangement suffers in this area. The steel pin through the plastic bolt cup was a great design move by TK its a shame they ditched it. Â As you seem more than qualified to answer, any thoughts on why they changed the design? Would this be cheaper to produce? Just hope they aren't dumbing things down. Quote Link to post Share on other sites
t_hum Posted July 16, 2011 Report Share Posted July 16, 2011 (edited) I dont know if Id say Im more qualified, but Ive tinkered enough and studied the KJW and alternative designs enough to identify the strengths and weaknesses. My GUESS is that KJW feels like the rubber band and piston cup system were costing them sales in the "realism" department. Tons of people flock the the WA for "realism". With WE switching to an open bolt design and that garnering a lot of attention and WA sticking to their bolt design perhaps KJW felt like they might gain from becoming more like the competition. Thats all speculation, of course. What has always made the KJW far superior in reliability and performance were the very differences they are now ditching. With any luck the new carriers will be awesome despite the changes. Â We have a completed WA bolt carrier design and it took about 8 months of tinkering to identify and rectify the problems. Our solutions might not be the end all be all of solutions for that style carrier but I can clearly see that the KJW addresses none of the problems we have identified with these types of piston to carrier arrangements. Â What Im most curious of though is whether or not TK had a hand in this. His designs are typically well thought out and many have served as the basis for countless gas systems used across platforms and manufacturers. The original KJW bolt carrier doesnt need much tweaking. The piston cup seal they use is a weak point which is why we made the x-ring pistons. Other than that though the system is rock solid especially where the other guys fall flat. Â My lengthy .02. Edited July 16, 2011 by t_hum Quote Link to post Share on other sites
Saberwing Posted July 17, 2011 Report Share Posted July 17, 2011 Any idea when we'll see these in North America? Quote Link to post Share on other sites
fadz Posted July 17, 2011 Report Share Posted July 17, 2011 (edited) Any idea when we'll see these in North America? Â I ordered it straight from KJ Works. Just message them through their website. Â You can ask them if they can ship it to you. May cost between 30-40 US$ plus shipping...I had it shipped within Taiwan since I was there already but they can ship it out anywhere. Edited July 17, 2011 by fadz Quote Link to post Share on other sites
fadz Posted July 18, 2011 Report Share Posted July 18, 2011 (edited) I fired the new bolt and the performance feels the same though I have not fired it in full auto yet. There is a crisper sound and a tad stronger kick in the blowback. Well, the bolt is heavier and is made with a stronger looking metal so it should kick harder...I don't have a magnet with me but feels like steel.  Things to do next: 1. Chrono test the two bolts and 2. Try to install aftermarket stuff in it like the RA Tech NPAS and Piston Ring  For the curious, here are more pics of the new version bolt:  1. View of Bolt (Rested) -  2. View of bolt (Bolt Lock)  3. Old and New M4 Bolts side by side:  4. The rear ends of each bolt. The new bolt is thicker with a nicer finish  5. My Bolt Catch now...noticed a slight wearing in the edge where the catch latches to the bolt. Will observe this in the coming days. Edited July 18, 2011 by fadz Quote Link to post Share on other sites
t_hum Posted July 18, 2011 Report Share Posted July 18, 2011 Keep track of wear on the bolt carrier where the bolt catch contacts it as well for us. Quote Link to post Share on other sites
slipknot1971 Posted July 18, 2011 Report Share Posted July 18, 2011 I just got the new version bolt of the KJ M4 in Taiwan. Bringing it home today and will test the performance over the weekend.  Here is a first look guys, please check it out. I want to install upgrades especially the Cradle Velocity Reducer. RA Tech told me their upgrades are compatible. T_hum, hope you can help...  1. Underside View:  2. The single moving part (piston) extended  3. Closer View of the rear of the piston...notice that the piston ring is facing rearward...  4. View of side... There is a screw in the ribbed part...I have no idea yet how to safely take this apart...any suggestions:  5. Front View   Questions!....does it come all assembled??...or we must buy part by part??...and as this is different from what's in the manual, this new system on the exploded numbered parts view doesn't exist....how should we order it? Quote Link to post Share on other sites
fadz Posted July 18, 2011 Report Share Posted July 18, 2011 It was shipped complete. Just slap it in. Â Just ask them for the new version m4 bolt. Quote Link to post Share on other sites
DiscoBiscuit Posted July 18, 2011 Report Share Posted July 18, 2011 It was shipped complete. Just slap it in. Â Just ask them for the new version m4 bolt. Â I hope they don't throw away the dyes for the old ones. Anyone have any opinions on whether this new bolt makes the KJW less importable? Quote Link to post Share on other sites
fadz Posted July 18, 2011 Report Share Posted July 18, 2011 I think they sell the stock gun with the old system. I looked as the airsoft retailers in Taiwan and the bolts are the same. Â This new bolt seems like their own aftermarket product (as of now). Â Slipknot, I just wrote KJ works...I first inquired if they sell the m4s with the new bolt. They said no but offered to ship me one... Quote Link to post Share on other sites
fadz Posted July 18, 2011 Report Share Posted July 18, 2011 I tested the two bolts using green gas, .2g bbs at around 25 Centigrade. 6.01 TBB, M4 length. Â Old Version Bolt (Replaced the piston ring with the RA Tech version) In the first shot, it gave out 520 FPS but settled to a 490 fps average. Â New Version Bolt Almost the same as the old one...490fps... ------ Â I really need to lower fps for cqb (other than using 134A). I wanted to make the new bolt my slap on CQB converter with a cradle installed but the lack of any schematic diagram (exploded view) or "jedi master" instruction on this new bolt prevents me from tinkering with it. RA Tech still has no instructions available. I will end up modifying the old one for CQB while reserving the newer one for the field. Quote Link to post Share on other sites
KAG Posted July 19, 2011 Report Share Posted July 19, 2011 Does anyone know what the currency is that is listed in the exploded view(in the KJW M4 instruction manual)? Quote Link to post Share on other sites
fadz Posted July 19, 2011 Report Share Posted July 19, 2011 Taiwanese dollars. About 28 twd per 1usd Quote Link to post Share on other sites
fadz Posted July 19, 2011 Report Share Posted July 19, 2011 Taiwanese dollars. About 28 twd per 1usd Quote Link to post Share on other sites
PapayaSalad Posted July 19, 2011 Report Share Posted July 19, 2011 Got a reply from KJW on the new bolts. They are $35 shipped to the US. I'm going to be using these as back ups on the field. Quote Link to post Share on other sites
slipknot1971 Posted July 20, 2011 Report Share Posted July 20, 2011 It was shipped complete. Just slap it in. Â Just ask them for the new version m4 bolt. Â Â All right thanks!!!...and it's not so expensive 35.00 USD shipped...and from the testings it looks like it could be a nice try... Â In Other news...today i managed to disassemble and assemble succesfully 3 lowers from teammates that were jammed....their cilinders suffered severe damage and the debris located under the fire/ safe selector causing jamming and impediment of movement...they are top of the line right now. Â ...I will post a wannabe guide to disassemble the lower to get the clean done...it's easy...just like a real ar-15 should disassemble...I will try some pics too... Â Cheers... Quote Link to post Share on other sites
_Samuel_ Posted July 20, 2011 Report Share Posted July 20, 2011 (edited) I was wondering how I could get Airsplat to replace my KJW M4. I recently sent it back for repairs and Airsplat claimed to send me a brand new gun. I got it back and it was the exact same thing. The day after I got it back, after about 15 magazines the internals started failing, once again, but they were failing worse than before I sent it to Airsplat. Now I am out of warranty and pretty much hating the KJW M4 right now. Â I would just buy brand new internals, but on the lower receiver were the front pin is at, a chunk of metal snapped off after one careful disassembly. Edited July 20, 2011 by _Samuel_ Quote Link to post Share on other sites
fadz Posted July 20, 2011 Report Share Posted July 20, 2011 All right thanks!!!...and it's not so expensive 35.00 USD shipped...and from the testings it looks like it could be a nice try... Â In Other news...today i managed to disassemble and assemble successfully 3 lowers from teammates that were jammed....their cylinders suffered severe damage and the debris located under the fire/ safe selector causing jamming and impediment of movement...they are top of the line right now. Â ...I will post a wannabe guide to disassemble the lower to get the clean done...it's easy...just like a real ar-15 should disassemble...I will try some pics too... Â Cheers... Â Looking forward to the guide bro...Once you set that up I am going to tinker with my lower receiver immediately...my team is moving to the KJ M4 platform and we need all the maintenance wisdom we can get. Quote Link to post Share on other sites
t_hum Posted July 20, 2011 Report Share Posted July 20, 2011 I was wondering how I could get Airsplat to replace my KJW M4. I recently sent it back for repairs and Airsplat claimed to send me a brand new gun. I got it back and it was the exact same thing. The day after I got it back, after about 15 magazines the internals started failing, once again, but they were failing worse than before I sent it to Airsplat. Now I am out of warranty and pretty much hating the KJW M4 right now. Â I would just buy brand new internals, but on the lower receiver were the front pin is at, a chunk of metal snapped off after one careful disassembly. Â Last I recall there were several members of these forums that went out of their way to help you with this issue. Im afraid this is largely between you and Airsplat. Assuming you can't resolve things with them your options are: Â 1. Repair the gun. This likely means asking nicely for a lot of help around here diagnosing the problem and finding parts. 2. Selling the gun. Â Good luck. Quote Link to post Share on other sites
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