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KJW M4

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What is "this?" The picture is pretty poor.

 

 

sorry, that is the nozzle. If you look on the upper right there is a clean cut where the gas enters from the mag. Is that normal?

I'm sure someone will beat me to looking at their v2 nozzles, but I'll have to look at mine tonight.

 

It's probably not normal, but I would just keep a careful eye on it for now, and see if it continues to get worse.

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If your referring to your upper and lower receiver not fitting tightly, like I think you are trying to say, this is not uncommon after a while of use. I know you said you bought this from Redwolf, but is it a used gun? I would think it would take longer than just one game for it to loosen up. I recently purchased a V1.1 from someone on my home forum, and mine has a slight "wobble" too. I don't notice it much since it is identical to my real AR. ARs aren't super tight.

 

You probably would have gotten away with opening the mag up, cleaning the valve and o ring, packing it with some silicone grease and then reassembling. These mags are pretty impervious to leaking, when clean and properly lubed.

Hopefully the paint helps to get the pins to retain better. Gluing them just sounds like a bad idea. You may need to service something some day, if it's glued that will be difficult. Just to clarify, are you saying that your hammer and trigger pins are trying to walk out? Or is it just the pivot pin and takedown pin?

 

Are you having inconsistent hop, or is it constantly under hopping? Also, what weight BBs are you using? One thing that is always a good idea, is to take your hop up apart and clean the bucking (or rubber as I keep seeing people mention on this forum). Clean it with soapy water, then rinse it and let it air dry. Reassemble after cleaning your barrel as well, and try not to get any silicone on the bucking. As long as the bucking had oil on it, you will not get consent hop performance.

 

Do not try to take the receiver extension (buffer tube) apart the same way you would on a real AR. It is not built the same. Instead remove the stock from it, look on the bottom of the "buffer tube" for a small hole. This hole has a set screw in it that you need to loosen. Next you need to unscrew the very large slotted bolt at the back of the "buffer tube". You can use the back side if a butter knife to accomplish this. From there, a couple people in this thread have suggestions on how to rig up the assembly. It's not too straight forward. Your other option is to order the CQB version's receiver end plate. It isn't like the ASAP, but it does have a sling mount built it.

 

The ASAP mounting instructions, I think, are somewhere in the last 80 or so pages. I just got done reading the 281 pages myself.

 

1. gun is new. That´s why is this woble weird for me. And this woble was from I put the gun out from box, not after the game.

 

3. mag are good now. I cleared all before and than after game too. Because I´m living now in Germany, I don´t have the gun here, so I will see what will happen with gas in mags after I come back to czech republic.

 

Gun was tested before game in woods but it rained so I didn´t take care about to set up Hop up perfectly. It wasn´t possible. I cannot complain on the hop up or the new inner barrel, it just needs to be set when I have time for that. I´m using 0,30g BB BLS. Gun arrived one day before game, so I haven´t enough time to do all things on this gun.

I know well about the oil on hop up bucking or inner barrel. Those I checked everytime. Both must be dry and clean.

 

With the pins, sorry I wrote it wrong. My english is not very good.

I meant that I will glue only those pins for trigger and hammer. I found after game that those two pins are moved to one side a bit. About one milimeter. It is not a lot, but it is ease to push them just by finger back in position. So they are not very tight.

 

The pivot pin and takedown pin are very easy to push out too. Takedown pin sometimes go out totaly and than I need small screwdriver to push that small safety pin in, than insert the takedown pin. It´s anoyng. I read here in this topic, that RS pins are much better.

 

About the Magpul ASAP assembly, thanks for the guide. I will try to solve this next time.

 

Thank you for your help Tank :).

 

yep and last question for everyone - something about the damage on mags and bolt ? Have somebody same problem ?

 

Thank you.

M

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Hello fellow KJW owners,

 

I purchased my first KJW M4 just a few days ago.  After reading through all 282 pages of this forum, I've determined it to be a V1.1, due to the piston and the fact that it appears to push on the buffer when I'm closing the receiver halves, without a cradle bolt extension installed.  It also does not have a weight installed on the bolt.  The previous owner installed a Cradle Velocity Adjuster but did not include any spacers, so I'll be ordering a set in the next few days, along with a V1+ bolt.  I like the idea of a quick change out for velocity adjustment.

 

I'm loving the gun.  Just yesterday I was able to shoot over 4 mags with just one propane fill, half of one of those mags was a full auto dump.  All other shots were done at about a half second pause between shots and the only pause betwwen mags was to quickly refill the mag with 32 BBs.  Needless to say, I'm ecstatic about the gas efficiency!  It was about 82F outside so there wasn't a terrible amount of cool down during the entire test.

 

I originally wasn't too happy with the hop adjustment.  The stock method to adjust the hop is way too restricting in both fine tuning and also the maximum amount you can apply.  I noticed the TDC mod on the Cradle website, and since I own a drill press I decided to give it a try.  For my first attempt, I tried to tap it using a M3-.5 tap, which was part of a cheap tap set unfortunately.  Since it only ended in me only striping the hole out, I then moved to a 6-32 tap and was successful. It was amusing for me to later read, in this thread, that T-hum was also using the 6-32 size tap.  After the modification, I was able to fine tune the hop for my .30 Biovals, or easily over hop them if desired.  My last test was very windy outside, so I couldn't get a real accurate gauge on what distance I could reach out to, but I would say 190 feet was easily attainable, using the Cradle velocity reducer with no spacers, on a 70F day and .30 bioval BBs.  I didn't think to chrono it at the time, so I'm not certain what the velocity was.

 

I still need to pick up extra mags and actually let it have its first day of glory on the battlefield, but I'm very impressed thus far.  I plan on putting a Primary Arms microdot on it, with possibly a magnifier, since all my games are outside, and eventually changing the rail out to something that I'm more accustomed to.  Something in the 12" rail variety with an AFG and MBUS.

 

On to the picture.  The guy I bought it from is also the guy on our forum that does all of our A-TACS custom painting, so it came pre-painted.

KJWM4.jpg

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Anyone know offhand what size grub screw Cradle is using for the TDC mods?

6-32 thread size.  The length wasn't really specified, I don't think.  I use 3/4" long set screws.  With that length, the set screw is just about flush with the top of the receiver, when the hop up is turned completely off.  I had a hell of a time trying to find that size available at any local store around me, so I ordered it from McMaster Carr.  There were two types I tried.  The first, part number 92313A154, is just a plain stainless steel set screw.  The second one I ordered is part number 91385A911.  That second one has a small nub of nylon sticking out the side of the screw for purposes of being a locking set screw.  I haven't shot any serious amount of rounds through my gun yet to determine if it is successful in locking the screw in place, or if I will need to put loctite on it anyway. 

Edited by Tank76

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6-32 thread size.  The length wasn't really specified, I don't think.  I use 3/4" long set screws.  With that length, the set screw is just about flush with the top of the receiver, when the hop up is turned completely off.  I had a hell of a time trying to find that size available at any local store around me, so I ordered it from McMaster Carr.  There were two types I tried.  The first, part number 92313A154, is just a plain stainless steel set screw.  The second one I ordered is part number 91385A911.  That second one has a small nub of nylon sticking out the side of the screw for purposes of being a locking set screw.  I haven't shot any serious amount of rounds through my gun yet to determine if it is successful in locking the screw in place, or if I will need to put loctite on it anyway. 

 

 

Awesome!  Thanks for the quick response, and the detailed info!

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Has anyone used the Hephaestus steel charging handles? I'm looking very hard at picking one up after shattering the POS stock one. Definitely a fan of the Badger style latch they have on it. 

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Has anyone used the Hephaestus steel charging handles? I'm looking very hard at picking one up after shattering the POS stock one. Definitely a fan of the Badger style latch they have on it.

 

Yes, I've got one of both styles. They are a VERY tight fit at first, and take some significant work to get broken in. More so on a v1 than a v2, but both take work nonetheless.

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Like sanding them down or repeatedly running the handle?

 

 

Both.

Wonderful, I'm going to order one today. Thanks Hut!

 

Sent from my DROID BIONIC using Tapatalk 2

 

 

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So I've found out that the RA and Falcon rubbers just suck, even with the TDC mod. I ordered 8 Falcon rubbers just to find out they're designed entirely different than the stock Part#20

 

One, the hop nub is more towards the front of the rubber, while the Part#20 nub is in the middle of the rubber, the hop arm is having trouble contacting the hop nub on the Falcon, as well as the nub being way too oversized.

 

Slight remedy to this. Dremel down the oversized hop nub on the Falcon rubber to about the size of the nub on the stock Part#20. Not perfect, but will subside.

 

Contact KJW for the spare parts you're having trouble finding. I ordered my Part#20s from KJW direct, $14.90 (for 2 #20s and S+H) later, and they'll be here (U.S.) soon.

 

Yea, i bought a falcon bucking with my also falcon TBB 363mm 6.01 knowing the couple of comments about it in this forum where poor, but expecting the best. After 5 games, I can say the performance IS an upgrade over the stock, but the nub is simply too thick like you say... with the dial all the way down, i still slightly over hop 0.28s shooting 2.3 J (the M4 length barrel, stock V2 valve) i was hoping it will break in a bit more and over hop less, but the break in period was quick.

 

It seems to climb from 0-100ft, maxing out at 4 inch higher at 75ft, then flatting out at 100 and staying flat as far as i can see. If i give it one click of hop, it will be a couple of feet high at 150ft lol... so no clicks for me. Effective range is probably 150-175, maybe more. At 140 ft (as long as i can test) i can hit a cardboard board (2ft by 5 ft, man sized) 8/10 times. All with 0.28s.... i ordered a stock new bucking bucking form KJW, but havent had the time (or need) to change it, it works fine.

 

Anyways, i finally used my KJ after a while a couple of months ago... here is a video, playing CQB, using a velocity reducer... 3 spacers 260 fps with 0.28s... im regretting putting music to it now...  :no: watch on HD, you can see how accurate it was from 2:40 on  :D

 

 

 

 

Question: I have removed a spacer since then, would 2 spacers and a 363mm get me to 350-380? I though 3 would get me there, i was surprised it was shooting so low (1 J) when they chrono'ed my gun on that game, maybe it wasn't releasing enough gas for the longer barrel.... im scared 2 would be too much  :huh:

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Some nice KJW pictures.

Figures. Right on the day I get the new Part#20 rubbers in, my V2 bolt cracks, and the loading nozzle spring breaks (again). And just when things were starting to brighten up.

I found that I just couldn't take the Falcon rubbers. Their 6.03 TB is nice though. I got the 509mm and cut it down with a pipe-cutter to about 457mm. Just the Falcon rubbers were really messing everything up. Also, I think the Falcon rubbers might be reducing the FPS. When I installed the Falcon TB and rubber, my FPS, on three rings, went from 321fps down to 282fps.

But this is Michigan, the temperatures here are NEVER stable, ha ha. So for me and my KJW, we have Mother Nature to contend with constantly.



Awaiting Cradle to process an order though I put out this past Sunday for the V1+, but Cradle is slow this time for some reason and I'm hoping bills don't catch up while waiting.

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Awaiting Cradle to process an order though I put out this past Sunday for the V1+, but Cradle is slow this time for some reason and I'm hoping bills don't catch up while waiting.

 

So you're from Michigan. Are you on MiA? By the way, I placed my Cradle order on last Friday, I believe, and I just got an email saying it shipped out today.

 

 

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So you're from Michigan. Are you on MiA? By the way, I placed my Cradle order on last Friday, I believe, and I just got an email saying it shipped out today.

Yes sir, pxranger on MiA.

 

And I too, finally got a notification through paypal that the order has been completed. The V1+ [should] be here before Friday. Can't wait to scratch that itch.

 

 

Also, was wondering if any US KJW users have an extra V2 BCG they wouldn't mind letting go. I got a friend who's V2 BCG straight broke on him, but he can't afford a Cradle V1+ at the moment. Could order from KJW, yes, but being stateside would cut down on the time it takes to email back and forth with them. Any help for my squad mate would be appreciated. Good chance to make some moolah through paypal. :)

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So you're from Michigan. Are you on MiA? By the way, I placed my Cradle order on last Friday, I believe, and I just got an email saying it shipped out today.

 

 

Yes sir, pxranger on MiA.

 

 

And I too, finally got a notification through paypal that the order has been completed. The V1+ [should] be here before Friday. Can't wait to scratch that itch.

 

 

 

Also, was wondering if any US KJW users have an extra V2 BCG they wouldn't mind letting go. I got a friend who's V2 BCG straight broke on him, but he can't afford a Cradle V1+ at the moment. Could order from KJW, yes, but being stateside would cut down on the time it takes to email back and forth with them. Any help for my squad mate would be appreciated. Good chance to make some moolah through paypal. :)

hui

 

Pm me. I think I've got 2, and would be willing to sell one.

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Hey all! I just recently became a member of the family!

 

I bought a used KJW and so far I absolutely love it! This is my 3rd GBBR in my shift away from AEGs. 

 

It's a V2 with a Noveske rail, Cradle velocity reducer, the TDC mod and I added the magpul furniture.

 

I also have the falcon hop up and 6.03 TBB on the way. 

 

I had a few questions for you guys.

 

  • There is a slight wobble between my upper and lower receiver. It isn't much but, but it's still annoying. Any known fixes?
  • After adding a B.A.D. Lever, when changing mags with the bolt back, if I use any amount of force putting another mag in, the bolt will automatically release and move forward. While convenient, I fear this may be due to wear, or some other problem. What should I look into for this?
  • With the velocity reducer, is there anywhere online that gives you an estimate with what FPS you'll get with the amount of spacers in it? I don't own a chrono, and would like to be within a new field's limits. (I'm aware that the TBB will also affect FPS, but it won't be here in time for the first game at the new field.)

BIDiUGM.jpg?1

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There is a table, way back in this tread, but it is extremely dependent on many conditions so your results will likely be different. Temperature plays a huge factor, and can move your FPS all over the board. Then there is the condition of your air seal, that can change your results pretty dramatically. If you knew one FPS result, at one temperature, with the cradle VA installed, it would go a long way in determining your expected results.

 

Sent from my DROID RAZR using Tapatalk 2

 

 

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Put some electrical tape between the gap close to the rear receiver pin. A small one would do...like a 2mm x2mm square should to it

 

Sent from my SGH-M919 using Tapatalk 2

 

That's exactly what I've done to mine. Now, I'm wobble free  :)

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