WE m4 - Bolt dont lock back

[Qlong]

I'm actually tired of seeing the same anti-rotation pins on everyone's gun lol. Seeing how the pins serves no mechanical purpose, I would go to with the most cosmetically appealing one, TSC is fine.

Stay away from their ambi-selectors tho, they looks horribly cast and finished.

TSC is pretty much the only one making an ambi-selector.

I'm going to start trying different RS left and ambi-levers to see how compatible they are with the WE.

[turok_t]

yeah tge TSC ambi selector looks horrible. I would MUCH prefer a RS ambi selector... i think im just gonna grab the anti rotation for the time being....just for appearance sakes.

[turok_t]

Hmm i just tried the mod and it didnt work for me I think the problem with mine is that, the lil notch on the magazine isnt strong enough to push up the bolt catch.. With the upper receiver off, and a magazine inside the lower receiver, i need to manually push the bolt catch out in order for the top to engage the bolt..


Any suggestions?

[Eien]

I'm trying this mod as well, i'm like 75% done since it's taking over 9000 with a file. Even tho, my bolt works fine, i'm trying to get this working with a B.A.D lever.

[Qlong]

Woops, sorry, I forgot to add one step, you will need to file down the opposite side at a higher angle as it will press against the receiver. You can't see it in this pic but it's already been done.

[Amos]

More pictures!

[turok_t]

Is there anything you can add/glue to the top of the actual part that catches the bolt? It seems like only a small segment contacts the bolt carrier

[Qlong]

Well that's the while point to this modification is not adding anything to the bolt carrier or the bolt catch.

You can try tacking a bit of weld onto the bolt carrier, I've done that, but this modding the catch is a simplest solution.

[Agent Carmichael]

Hey Qlong, this is very helpful indeed! Thanks for taking the time to explain and to illustrate the mod. I made the mod as you've suggested, works like a charm!

[Boris the Blade]

I believe the problem lies with the stopper on the mag that is raised when the mag is empty. TSC has released a refined part that is built to catch better by the bolt catch. I'm hoping that by installing this part into WE M4 mags will solve the problem. The name of the part is TSC bolt catch plate for WE GBB M4/SCAR.

On a related note, if your bolt catch doesn't work even when you try to catch it manually without a mag in, there are a few things to check:
- check if your bolt catch is worn down
- check if your bolt carrier is worn out
- check that your buffer tube isn't screwed in too far, if it is it will cause your bolt to short stroke and stop your bolt from catching.
- check that the rubber stopper in the back of your buffer tube isn't too thick. This was the case and caused my bolt to short stroke.

[Qlong]

Even if the pin is pushed all the way up, the bolt catch will still be limited by the upper receiver wall. The TSC parts will work if your stop is relatively new, however if it is heavily worn, you will still need to modify the stop.

[Boris the Blade]

I'm gonna do your mod, Qlong, and I'll post my results here tonight.

[Boris the Blade]

So I just did the bolt catch mod, it catches SO much better now, however, I still cannot get my bolt to lock back during firing when the mag is empty. I confirmed that my mag is set to regular mode (not dry fire mode) and it is still not catching during firing. It does however catch when I put in an empty mag and rack the bolt (catches on its own) and catches when I engage the bolt catch regularly during firing (with an empty bolt).

When I fire the gun with no BB's in the mag the gun shoots great, but the bolt doesn't catch.

I suppose it's worth mentioning what setup I have -
Newest gen WE M4A1 (I believe its Gen 5?)
Polished bolt
Polished Brass tube
RA-Tech NPAS
Brand new magazines