Jump to content

GHK GBB AKS74U Review


Recommended Posts

Dear All,

 

Hello, this is Henry Wang of RA-TECH.

We got new product again.

 

RA-TECH aluminum Bolt for GHK-AKS-74U

http://www.intrudershop.com.tw/redalert/pi...for_GHK_AK).jpg

 

As my customer service experience, some custmers will tell me that their nozzle is deformed.

Therefore, we decied to product the stronger one for you.=]

 

If you got any questions, please be free to contact with by e-mail,ra.ssh5915@msa.hinet.net .

 

Thanks!

 

Best regards,

 

Henry Wang

RA-TECH Customer Service

Link to post
Share on other sites
  • Replies 167
  • Created
  • Last Reply

Top Posters In This Topic

aye bolt carrier def needs a redesign/better material or both

 

Seen a few folks report snapping at that screw mount, and I've got one where one of the lower tabs has broken off the blowback chamber (lets the piston drop out of place when its fully extended) Casting small 1 or 2mm square unsupported tabs in pot metal dont strike me as too clever from a longevity POV.

Link to post
Share on other sites

Played with one of these at Blackhole yesterday... I'm no GBB rifle fan by any means - but it was FUN! Also, I really liked how the internals are so similar to the real-steel weapon. As soon as I opened up the dust-cover I was able to recognize and understand almost every component.

 

Definitely will be ordering one in a month or two.

Link to post
Share on other sites
can you guys take pics of the problem? I am looking at my gun and I am so dense, I cant figure out what you're talking about...

 

heres compilation of photos taken from a users post on gas guns info

 

breaks-1.jpg

 

1st is the broken bolt issue (snaps off where it meets the nozzle and its pin)

2nd is broken bolt carrier issue (snaps off where the brass pins screw into the cast pot metal bolt carrier)

3rd shows the small tabs that can break off the bolt carriers blowback cylinder (theres three in total one at top one towards the bottom at each side)

 

drops.jpg

 

and heres a horrible sketch that I knocked up to show what happens to bolt at full recoil stroke when one of the lower tabs is missing/broken off

Edited by snorkelman
Link to post
Share on other sites

Interesting - no problems with mine yet. I will be getting the aluminium bolt but it looks like a steel / aluminium bolt carrier might be required. Any chance of that RA-tech?

 

And is there any preventative work that should be done to reduce the chance of a breakage? Perhaps put some rubber sheath around the brass screws to lessen the impact or something?

Link to post
Share on other sites

chamber tabs - I dont like them (they give me the judders to see teeny bits of pot metal cast unsupported on three sides out of four) but in fairness the only broken one I've seen thus far is on my own. When in the gun they shouldnt be anywhere that would take a knock

 

The main issue looks likely to be when the bolt carriers are getting shipped as components (from GHK to RA from RA to end user etc) as that would be when they were most likely to take a knock against other components in the shipping box. Mine was cracked on lower right hand tab straight out the packet.

 

Only other time they're going to be in a position to take knocks is when you're removing the bolt carrier from the gun etc.

 

 

Bolt carrier pins - seems to be the less meaty left hand side of the bolt carrier thats been reacting badly in the ones folks have mentioned breaking thus far

 

If you lift up top receiver cover you can see that thats probably exacerbated by the construction of the barrel trunnion at that side of the gun (it really only strikes half of whats already a pretty thin face of the bolt carrier on that side - concentrating the load on an even narrower spot)

 

there isnt really any spare meat on the carrier itself to add a rubber buffer or sleeve the pins, I'm waiting for a hop unit for this one to arrive (was missing from the kit) so can't see wether there'd be room to incorporate a small buffer at base of the recoil spring guide part (or wether thats completely concealed by the hop unit)

 

Inside the front of the casting of the bolt carrier is a recessed area which forms part of the tube the recoil spring guide rod goes thru That might be another candidate for packing with some rubber washers to act as a bump stop

 

Likewise you might be able to glue a small thin strip of rubber inside the barrel trunnion on left hand side - thin enough that it doesnt rub against the side of the bolt carrier, but long enough that it projects back from the barrel trunnion far enough to absorb some of the impact of the bolt carrier striking the trunnion (just a teeny bit projecting out from the trunion - a mm or less)

 

Final option might be a much stronger spring on the interupter/hammer delay/'whatever you want to call it' lever, so that it actually gives a little bit of resistance against the bolt coming back into battery and takes a bit of the sting out of it

 

Course thats assuming:

 

A - that the presence of the interupter on the right hand side of the receiver isnt already reducing load on right hand side of the bolt carrier and transfering it to the left. In which case a stronger interupter spring would just exacerbate that (it provides so little resistance in its stock form though that I doubt it)

 

and

 

B that the extra force then absorbed by the heavier-sprung interupter doesnt end up causing premaure failure in the interupter lever itself lol

Edited by snorkelman
Link to post
Share on other sites

I have added a buffer onto the recoil rod in a typical Blue Peter fashion - the top funnel end of a Marui AEG loading rod suitably bored out to accept the recoil rod, a cut off recoil spring from a GBB (about 4mm long after trimming, and 2 O-rings over the end of the recoil rod before it goes through the spring and funnel. The funnel had to have one side flattened slightly with a file to fit inside the gas block but the buffer now stops the bolt carrier slamming against the trunnion.

 

Time will tell I suppose....it still shoots fine but has a 1mm gap between the front of the bolt carrier and the front trunnion.

 

I would still eat a steel carrier up for the right price though...

 

:cookiemonster:

Link to post
Share on other sites

the rubber block inserted ahead of the guide-rod/pistol grip mount on the GHK carries out equivalent function already (rearward point of contact on the airsoft bolt carrier is different from real deal).

 

Seems to be the impact on forward part of the stroke thats causing the wear - e.g. other than a mag or two mines mainly been dry cycled thanks to the leaky mag valve and lack of hop unit, so rearward forces were minimal yet still shows signs of impact wear at front just from allowing the bolt to come back into battery under tension of the spring.

 

I think your buffer at the front mod will probably be the better end to tackle it at

 

Link to post
Share on other sites

looks like problem one you had snorkleman is the exact same problem i had as it broke the exact same way and everything. my replacement is currently functioning fine but i have plans to upgrade the piston when i get a chance to or this one breaks after the weather breaks and i finally skirm it

Link to post
Share on other sites
  • 3 weeks later...

got my aluminum bolt yesterday

 

quality is very very good!

its machined precise and nicely black anodized

 

fits perfectly inside the bolt carrier, only the o-ring is very tight fit and doesn't move easily

ill try to fit the o-ring from the plastic bolt, maybe this will help

 

but it works perfectly and shoots maybe even better then before (cause of the tight seal i guess)

 

i also noticed that my bolt carrier is broken on one side like some users reported already =/

 

lets hope ratech will make a bolt carrier of better material soon

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use and the use of session cookies.