M4 front pin

[sopmod]

Hi, ASC members. I recently bought KA M4 body. it is awesome piece. however, after i assambled everything include the gearbox, motor, and barrel, i can't push front pin back in. When it received it, the pin was fit in the body perfectly, but whatever i try, it does not go in.

Does anyone can solve this problem??

thanks

[Shirley]

Your upper reciever is not in place yet. Check your alignments, and also the upper internals, and then your gearbox fitting.

[sopmod]

No. I do not think my internal has any problem. the pin is located at end of lower receiver. somehow, it does not go through upper receiver.

[Shirley]

Originally Posted by sopmod

No. I do not think my internal has any problem. the pin is located at end of lower receiver. somehow, it does not go through upper receiver.

Okay, I know that. The top upper has to slide together with the lower, correct?

It's obviously the allignment of the upper and the lower. It's easier to look through the hole and see if it's smooth flat through.

Use some silicone oil too.

[Styrak]

Are you shoving the upper back HARD while you hold the lower and push the pin in?

I've worked with a few metal bodies and they were all fairly tight fits, which is a good thing.

[Shirley]

Originally Posted by Styrak

Are you shoving the upper back HARD while you hold the lower and push the pin in?

I've worked with a few metal bodies and they were all fairly tight fits, which is a good thing.

I've lost about 3 already when I was using my stock TM lower.

I used to have the DBOYS metal body where it came with the screwing locking pins, where you have to screw one side into the pin with an allen key which was awesome.

[sopmod]

yp. mine is sliding upper.

i guess it is just aliengment of my body, but it went in after i took the chamber out !!?? Does chamber even effect anything??

[Shirley]

Originally Posted by sopmod

yp. mine is sliding upper.

i guess it is just aliengment of my body, but it went in after i took the chamber out !!?? Does chamber even effect anything??

You mean the fake bolt? It's just for looks, and sometimes blocks water and dust from coming into the gearbox. Dust cover works like that too.. lol

I heard the new KA have the new locking bolt feature.

[sopmod]

i meant hop-up. sorry. new KA chamber locking system is pretty cool. easier to adjust the hop up, but it only lock at about quater when it is opened.

[Shirley]

Originally Posted by sopmod

i meant hop-up. sorry. new KA chamber locking system is pretty cool. easier to adjust the hop up, but it only lock at about quater when it is opened.

lol That's why it's so expensive..
Anyways, you need the hop-up and everything that was transfered from your old body..
Try pulling the upper and lower together, like bash it in with force, but not too much. It usually works for me.

Oh, wait, check your hop-up and inner barrel if it fits inside the outer barrel and the upper. It should spring out a little when being pushed.

[sopmod]

it is little bit expencive, but i think it worse though. you know.. when you try to adjust hop up, you have to pull and hold the charging handle. Now I do not have to do it... just lock the dammy bolt..=)

thanks for help. i just try little bit harder on it..XD

[ybrik]

Sopmod,

try to secure the gearbox on the lower receiver with the gearbox pin (small pin at the middle). Don't put the rear lower gearbox pin yet and see if it will fit.

Another thing to try, don't tighten the screws of the pistol grip to your gearbox. Do this the last thing when you have already secured your upper and lower gearbox.

[m102404]

Depending on the mechbox, the fit may be a bit wonky.

Try this...it may not be the final fix/answer...but it might help to figure out what's going on.

Remove the grip/motor

Pull out the rear pin.

Tighten the rear stock screw...pretty tight...overly tight compared to how tight you would normally do it up. This will pull the mechbox back a bit.

Slide on the upper, with the hopup in....see if the pin will go in. If it's still stiff, it's not a great idea to just wack it with a hammer...you might crack the lower frame. You can squeeze it in with big channel lock pliers (use something so you don't scratch things up...cardboard works).

If it goes in, great...but now you have to loosen off the stock screw and see if you can reinsert the rear pin. If that works, then reinstall the grip.

Best of luck,

Tys