[SOLVED] WE Scar Open Bolt Nozzle breaking, looking for input. (seems like a magazine shimming issue?)

[XOIIO]

Hey all, so I was hoping I could get lucky with my newly purchased open bolt scar, however it looks like I got stuck with the loading nozzle breaking issue as well. Don't get me wrong, I was expecting that it could come with some quirks, when it does fire properly it's freaking awesome and sounds great, I just haven't seen a thread that was that in depth in regards to the loading nozzle issue, or that wasn't a quick fix. This could be due to me using the repaired nozzle however, but it should be pretty darn strong with jb weld.

I'm also using .20g bioval bb's, maybe they aren't dense enough to withstand full auto fire?

All of my tests were with a max of 15 bb's loaded, usually much less, so I wasn't pushing the magazine up to it's fully capacity (I wanted to break it in first)

Basically, it worked fine for semi, and a couple short rounds of full auto, then it double fed, jamming one bb in the spot where the loading finger is supposed to fit, cracking it and pushing the hop up assembly apart a little bit, breaking the loading finger).

I repaired the nozzle with CA glue, and it worked a couple rounds then broke, I had just wanted to see if it would break in the same fashion.

So, next time around, I used some JB weld plastic epoxy, the quick set stuff, and I shimmed one magazine with some fairly thin washers, they are m4 ones as I couldn't find any smaller ones at that store, they won't be my long term solution.

I slowly fed bb's in manually, popping them out of the hop-up with some tweezers, and it fed them through and felt much smoother than the non shimmed magazine, worked fine on semi for a bit but then broke, so I cleaned off the jb weld and went for the classic much stronger stuff, and let it sit for about 15 hours (Should have gone longer but I was impatient lol).

Anyhow, fired about 10 shots semi auto with the bolt locking back one time even though the mag wasn't empty, but aside from that no issue. Loaded four to test full auto, all good there too, so I loaded in 15 rounds, fired two or three semi, then switch to full auto and I got two shots out before the nozzle broke again and the bb got jammed into the spot where the loading finger is supposed to sit again, being cracked.

The gun is virtually new as are the magazines from what I can tell, the spring feels nice and stuff, so it should be feeding them in quickly, though the issue is only cropping up when I do try to shoot full auto.

I have a couple more loading nozzles on the way as well as an npas kit to be field legal, and the latest breakage could be because I didn't let the jb weld set for a full 24 hours, but I am hoping to fix this issue before putting a replacement $27 nozzle in, as it would just be a waste to have it break right away.

I'm thinking I'm on the right path shimming the magazine feed lips, possibly I need to lift them up a bit higher, I have also seen in other topics feed issues that required gluing some plastic in the mag well to make the magazines sit a little further forward and with less wobble, but I didn't see the nozzle breaking issue in relation to this.

Someone on reddit also mentioned it could be the hopup assembly being out of alignment but I took the gun down to that level, and it's nice and solid, I'm thinking perhaps the screw holding the hopup together could be tightened a bit, and that might help with the bb getting forced into the loading nozzle spot, but using gentle leverage I'm not able to force it wide with any ease like the bb does, though it is very slight (picture of this and the end of the post).

I have to get a smaller allen key to get the hopup unit out, but I'm just hoping that I could get some input from someone else who has dealt with this to see if I'm on the right path, or if I may have missed something along the way.

The gun was purchased at some point last year, so it should be one of the newer produced scar 17's.

Here's the bb jammed in, and you can see how it slightly spread the hopup unit apart at the top. On the bb itself I can see what looks like an indentation from the loading finger so the jb weld was cured quite well, it just seems like the bb wasn't sitting high enough.

If anyone has pictures of their shimmed magazines vs unshimmed so I can see how much you lifted the feed lips that would be tremendously helpful.

Also another side note, I was impressed to find spring loaded captive screws, that's a nice quality touch, though they are retained with o rings, so if you have a particularly old gun they could crack and send the screws flying.



Edit, mostly as a spot for me to find this again later on, I did find this thread where the last post mentions that the open bolt nozzles can be slightly too long and need to be shaved down, I don't think that's my issue, but putting it here so I can come back to it. http://www.airsoftforum.com/board/to...amming-issues/

[Danke]

Missfeeds break the nozzle. You need to spend some time paying attention to what's happening and figure out what's causing the missfeed.

I like the metal nozzles. I know they do get hated on a bit for being hard to setup but at least you just crush the BB on a missfeed. Constantly springing for a new nozzle is a drag.

Not sure about a repair. I'd suspect that while you could get it good enough to cycle there would be underlying issues that would continue to cause you problems.

[BioRage]

Expect anything WE to break, get a aluminum nozzle; and while you're at it, just full upgrade it.

- Don't use bio's in gbbrs, yes there may be some "good quality" ones, but use non-bios like Krytacs
- as Danke said, misfeeds cause issues, you need to check/clear chamber as required
- your bucking might be swolen, not a bad idea to replace it while you're at it with a maple leaf

[XOIIO]

Alright, well, problem solved, or at least, I'm 80% sure lol, not going on 100% yet. On the bright side, I do enjoy solving problems like this, granted it's usually electronics, and now I know my gun pretty thoroughly, except for the trigger assembly.

First things first, turns out the gun already had an npas valve in it, awesome, I need to see if I can return the one I bought and just buy the tool, as I don't need a spare vale (I'd rather put the money towards a nice ish optic or some mags.

Second, I got some m3 washers and shimmed the mags with two each, this ended up not being good, the gas seal at the top of them has had a bit of contact so I only used two washers to shim the mags, I could unshim them completely but I'm not totally confident in that.

What I did which seems to have really fixed it is shim the magwell, I saw in one video somebody had done this to fix the feed issue, so I cut the magstrip out of an old gift card, cut it down to fit nicely in the lower section on the right that you can see in the image below. hit it with some sandpaper and used some CA glue. The magazines are nice and tight now and sit a little bit higher up at the front.




This worked really well, after about 40 shots or so my repaired nozzle cracked again so I replaced it, moving the npas valve over to one of my two spares, part of the back section was cracked off too so that probably didn't help with it's alignment.

I've put around 90 rounds through now and I haven't had a single issue, she's purring like a kitten, except for when I put the npas in and accidentally set it to vent most of the gas making the bb's basically drop after 6 inches lol.

I can't say it won't break another nozzle any time soon but I finally have a good feeling lol.

I remember seeing some sticky white cloth ish stuff in the magwell when I got it, I took that out figuring it was some shipping crap, but thinking back the mag was in there so that was probably shimming by the previous owner, d'oh.

Anyways, time to clean out the factory lube, use some 20wt silicone in some areas and a thin coat of lithium grease for the bolt to really get her in nice operating shape.

@BioRage, I did see the aluminum nozzle and almost bought it but apparently they have issues sealing sometimes, and don't work well with npas, and it would risk breaking something else if it misfeeds, instead of snapping the feed arm and preventing further damage, in theory.

I do want to get a tan modify bucking or something similar, don't know if that's the maple leaf one you speak of but that's on my list for sure.

Also, bio bb's are required at our fields IIRC, and personally I don't mind spending the bit extra to not put a bunch more shitty plastic into the environment

@Danke that input about the metal nozzle is helpful though, have you had any issues with sealing? Not sure if you speak of the aluminum one, or a steel one I read about once I think, the main thing I saw with the aluminum ones is that they would bend upon a misfeed. Smashing the bb to bits would be preferable to a nozzle though, and the hopup assembly does feel pretty skookum.



Anyhoo, side note from all this, if anyone knows of a 7.62 suppressor that works with the scar's flash hider thread, in black, that would be awesome, I can't figure out what the large 1 or two turn thread is called, or what that style suppressor would be.