KJ M9 Blowback Unit replacement

[Red62]

6 years and my M9 finally bit the bb, just stopped fully racking and now it doesn't slide at all. Tried out my mags on a different gun, they work fine. so the question now is where can I find a replacement blowback unit?

[Styrak]

Why are you so sure it's the blowback unit?

[Red62]

magazines are fine: tested them myself in another gun. I don't see why it would be the hammer, but I should try it out tomorrow. right now im trying a hot-swap troubleshooting technique with an Aftermath M9

[Styrak]

It's unlikely that it's the blowback unit. Nozzle maybe, or valve inside maybe.

[apilar]

I had a blowback unit fail on me. The blowback is kind of strange in my oppinion.. its much less of a 'unit' than a 1911 which is what im familiar with. Nonetheless, i do have an m9 and it did fail.

It sounds like you are describing exactly what happened to me. For example, i dont know if you run green gas or co2 but my gun can run either and the green gas mag failed to cycle the gun at all so the problem was easier to diagnose with co2. Brand new co2, would shoot about 23 shots and then the slide would half engage the hammer. The bb would fly as normal the slide just wouldnt go back and forward to catch another bb. By manually racking the slide it seemed to shoot fine.

After FINALLY figuring out it wasn't any of the barrels i was experimenting with I check the blowback unit. With the slide off pull the nozzle out/down, as if to check if the springs are working. Now what you should see is a black piston inside with a rubber seal on the end. What i saw was the top inside of the slide. My piston had snapped at the base right where it turns into the loop to allow the safety selector through. So the rubber seal was actually stuck inside the nozzle and just kinda banging around in the gun. Made sense for the first 23 shots or so to shoot fine because the pressure of the co2 was so high and could still make the piston somewhat effective.

Look at your piston but pulling it down/out - hope ya know what i mean by that - and see if your piston is still in 1 piece.

If you do find it is broken - evike, uncompany, buyairsoft

[LocoYokoPoco]

If you contact KJW directly, they will sell you replacement parts. Just send them a message with the part # and qty you need and they will get back to you. (may take a while though).
http://www.kjworks.com.tw/main.php?lang=en