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Thanks Luis. I believe I had just resolved the issue with my loose RIS :

 

There is a small tab that sticks out at the bottom of the front sight when looking at the end with the gas tube hole (this may be particular to the RIS version only), and it was broken off. Originally I thought it was just a scratch mark on the front sight where the tab should have been, but upon further investigation I figured out that a tab should have been there to connect into the bottom front end of the RIS to secure it from sliding or spinning left and right (if you look into the top RIS plate you'll see 3 holes - top one is for the gas tube, middle is for the barrel, and the bottom tiny one is for this tab/pin). This works in conjunction with the fake gas tube and the channels that Luis had mentioned in securing the RIS so without the little tab, the RIS was free to rotate around, thus making it slightly loose and wobbly.

 

To fix it, I drilled a hole into where the tab should have been, using a 1/16" drill bit and found a small pin that is the perfect size and glued the pin into the hole. See below. The tab/pin is above the barrel:

 

3754821052_9855417ef3_o.jpg

 

With this pin/tab in place, there is ABSOLUTELY ZERO play in the RIS now and the gun feels like a solid piece of brick instead of the slightly wobbly mess that it was in when I received it.

 

I also had to take apart the delta ring set because they were assembled incorrectly. This is what it's supposed to look like.

3754856460_166fda5439_o.jpg

 

Notice all the small scrach mark near the receiver end of the barrel. The weld spring and snap ring were both there when I got the gun. Took me awhile to understand the mechanics of this set before I proceeded to correct the assembly of this portion.

 

 

The gun in stock form. I love the RIS look without the covers... :lol:

3754821138_340d85b220_o.jpg

 

Next up - lubing and cleaning the interior. The gun is bone dry with little lube on the components but thankfully not a lot of wear mark. Time to find myself some gun grease and silicone oil to lube this baby up.

 

It's funny because I've already spent a few hours on this gun but haven't even fired a shot yet :P This shows you the kind of QA control that AGM has for this gun but for the price what do you expect, I suppose. I sure hope that my mag is okay because god only knows how long THAT will take me to figure out how to disassemble (I'm a total noob).

 

So far I had to:

 

 

- disassemble front barrel assembly to tighten the barrel nut

- reassemble delta ring components because the snap ring and weld spring were misplaced (both were behind the notch on the receiver end of the barrel, instead of in front)

- disassemble buffer tube and stock and tighten both/put black electric tape inside the stock

- fix the missing pin/tab on the front sight so that the RIS can be secured

 

Looks like there will be more work to do once I start working on the internal stuff.... fun fun fun ;) And I"m really slow as well since this is my first GBB rifle so I have to double and triple check all the parts and components, read some info online pertaining to the design of the real steel version, and then proceed on taking things apart.

 

I will definitely need help soon with replacing certain parts with more durable replacements, but I don't think I will be throwing down as much cash as some of you have already because I'm a collector and only plink in the basement once in awhile. I'm thinking a bolt catch, front loading nozzle, and hop-up bucking (or even the whole hop-up assembly) should last me quite some time.

 

Can't wait! This is fun! :lol:

Edited by Bonjour43ma
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The new 5KU or SK mags have a stronger spring and seem to engage the bolt stop no problem. The one I tested were a pretty tight fit in the mag well though.

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The hopup replacement for AEG barrels:

ae25a669.jpg

Edited by KWP
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I wouldn't have thought so. Just a case of whether it fits in the magwell ok and if the valve lines up with the firing pin. I know the AGM mag has problems in G&Ps and the 5KU mag is supposedly an improved clone of the AGM. I'm just wondering how improved it is.

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It's funny because I've already spent a few hours on this gun but haven't even fired a shot yet :P This shows you the kind of QA control that AGM has for this gun but for the price what do you expect, I suppose. I sure hope that my mag is okay because god only knows how long THAT will take me to figure out how to disassemble (I'm a total noob).

 

Looks like there will be more work to do once I start working on the internal stuff.... fun fun fun ;) And I"m really slow as well since this is my first GBB rifle so I have to double and triple check all the parts and components, read some info online pertaining to the design of the real steel version, and then proceed on taking things apart.

 

Aye best way to do it, after all its not a race

 

I actually spent best part of a week (possibly even a whole week) on mine prior to it firing a shot - parts checked, function checked, stripped, compared and checked again.

 

best tools in anyones workshop are patience, an understanding of what you're working on and attention to detail, they're also the cheapest :)

 

 

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I knew exactly what I was getting with this gun, I got it because I knew I'd have to open, replace, check, and double check parts. Since this was my first GBBR this was a better choice to LEARN. And after finally finishing my GBBR so it is skirmishable, I can confidently say I know more about GBBRs to help others and buy more in the future. G&P is nice but I'd still buy another AGM to fiddle around with :D

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@Bonjour43:

 

Very nice fix my friend. The little tab on mine is broken as well. I need to borrow a drill myself to do that little mod.

 

And I will post up a little review about the PGC hop-up copy as soon as I get my gun shooting.

 

I will also get 6 of the 5KU magazines.

 

-Luis

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Just a question out of curiousity, but:

 

Does anyone think a V-hop up would work with the PGC aeg compatible hop assembly (or its copy)?

 

I noticed that the provided hop rubber has two flaps on its side to hold it in place in the assembly, so that might be a problem and require modification to the V-hop.

 

-T.S.

Edited by T0p Sp!N
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FULL rifle strip down (and I mean 'every last nut and bolt' full lol) - this guide is from memory as I wasnt about to take that rifle completely apart again just now, so if you want it with a huge bundle of photos gimme a week or two and I'll photograph next one as I take it apart.

 

This guide isn't in best possible order I'll tidy it up for photo version (which would probably be best in a thread of its own with an index) - its really just the easiest way for me to work thru it in my head and be sure I dont miss a chunk.

 

Things like reassembly of fire control parts really do need a section of their own to cover proper placement of the springs, how the parts interact with each other, how to get the springs back in right places and check for proper function I'll see what I can come up with for that (probably the parts attached to a board so you can see side on how they interrelate without a receiver in the way)

 

 

Note that as a full strip down it includes disassembly of parts that you wouldnt normally be removing or taking apart

 

 

 

push both receiver pins

 

seperate upper from lower

 

draw back charging handle and remove it and the bolt carrier group from the upper stick that lot to one side for now

 

 

lower receiver strip this is pretty much all in one go but I'll divert to stripping the sliding stock during it at an appropriate stage

 

remove the rear takedown pin from receiver - its detente is captive in the lower and wont come out

 

push the front pivot pin back into the receiver for now

 

depress buffer lock pin, remove buffer and recoil spring

 

knock pin thru that holds the auto sear, watch for the white plastic clip on the pin

 

remove auto sear and spring (turn receiver upside down and give it a shake if the white plastic clip evaded your grasp while drawing the pin out)

 

remove the selector by pushing it thru the receiver while set between safe and semi - keep an eye on its detenete pin and spring

 

knock hammer pin thru

 

remove hammer, hammer bushings and hammer spring

 

begin to knock trigger pin out

 

as trigger pin starts moving out of receiver, keep hold of the spring loaded semi auto sear (the triger pin passes thru that as well)

 

with pin two third of way out its now clear of the semi auto sear remove the sear and the sears tensioning spring from the trigger at that stage

 

press the trigger pin rest of the way out

 

remove trigger and trigger return spring

 

undo pistol grip screw (use a 4mm allen key thats around 100mm long minimum to reach it)

 

remove the screw and the washer below it

 

remove pistol grip

 

remove captive nut the pistol grip screw screws onto

 

undo the allen screw on lower that was hidden under the pistol grip

 

remove the alloy mount inside the lower that holds the spring loaded buffer retaining pin and spring loaded selector detente, these are just placed inside the block rather than screwed or pinned onto it, so be careful they dont go in five different directions as you draw the block out

 

 

at this stage I'd remove the sliding stock before removing buffer tube

 

loosen the small allen screw that is used to lock the round nut on sliding stock locking latch

 

loosen the round nut a few turns

 

pull down on the sliding stock locking latch, so the captive bolt head clears the 6 position mount on the buffer tube

 

slide the sliding stock off the buffer tube

 

remove the round nut from sliding stock completely

 

remove the plastic latch

 

remove the bolt and spring from the sliding stock

 

unscrew the sling mount retaining screw from stock (philips head)

 

knock out the captive plastic nut

 

sling mount should be free of the stock

 

sliding stock removed and stripped

 

 

lower strip continued

 

returning to the lower, loosen the castle nut on buffer tube using armourers tool, C-spanner etc

 

draw the lower receiver tower end cap back along the threads on the buffer tube (unscrewing the castle nut as neccessary to provide room for the end cap to move backwards) watch out for the rear take down pin detente spring that will start to merge as the end cap is with drawn

 

when you get the end cap back far enough that its clear of that detente spring, unscrew the buffer tube from the lower receiver tower (the end cap will turn along with the buffer tube as its keyed to it so make sure it doesnt slide forward and mangle the take down pin detente spring)

 

finish unscrewing the buffer tube and set the lower to one side

 

remove the end cap and castle nut from buffer tube

 

go to buttend of the buffer tube and undo the small grub screw on underside of it

 

unscrew the buffer tube end cap from buffer tube

 

buffer tube now completely stripped

 

lower continued

 

pick up lower receiver again, remove the rear take down pin detente spring from the rear of the lower receiver (just pulls out)

 

remove the take down pin detente from the lower receiver (if it hasnt come out along with its spring)

 

push the front takedown pin out as far as it normally goes - it'll hangup on its detente pin as usual

 

now carefully push the pin a bit more to get it clear of the right hand lug, while watching out for the detente pin and spring that will be released when its removed - best to do this with front of the lower receiver pointed into a cardboard box etc, to catch the pin and spring if they do go shooting out past your fingers

 

next push the mag catch release button in as far as it can go so the mag catch clears the lower receiver

 

holding the button in unscrew the mag catch from the receiver

 

with mag catch unscrewed, draw out the mag catch release button threaded rod and spring

 

the firing block is now free of the mag catch rod that was passing thru it

 

remove firing block from the lower complete with bolt catch

 

be careful as you remove this part, as theres a small spring (near top right of it on bolt catch side of the lower receiver) that is being compressed against inside of the lower receiver

 

firing block strip while its in your hands heres the strip procedure for it

 

remove the spring mentioned above

 

remove captive detente pin thats behind the spring

 

knock the pin that the bolt catch pivots on out

 

remove bolt catch

 

undo the allen screw that holds the two halves of the firing block together

 

sperate the firing block

 

remove the valve knocker and spring thats inside it

 

firing block now stripped

 

 

back to the lower one last time

only thing left in lower receiver now is the trigger guard - ordinarily never remove it unless you have to, but as this s a full strip down guide removal is as follows

 

support the receiver with some blocks of wood etc - its especially important to support the lugs the trigger guard sits in

 

with it well supported, use a drift of the correct diameter to knock the split pin out that holds the trigger guard in place - the pin punch/drift that you use should be narrow enough to fit inthe receiver lug and wide enough to make contact with the hollow split pin

 

knock the pin out the whole way thru, do NOT pivot the trigger guard out of the lugs when the pin has reached point its cleared the guard but is still in the lower lug - instead keep knocking untill the pin is completely free of both lugs first (the guard sandwiched between the lugs will give better support)

 

with split pin removed, depress the spring loaded detente in the front of the trigger guard to allow its removal from front lug

 

undo the hex grubscrew in the trigger guard, then remove the grub screw, remove the small spring beneath it and remove the detente

 

trigger guard is now fully stripped

 

lower is now fully stripped

 

charging handle strip down

 

knock the split pin out that holds the latch in place

 

remove the latch

 

remove the plunger and spring behind the latch

 

charging handle now stripped

 

bolt carrier assembly strip down

 

remove the small eclip at rear of the blow back chamber (about half way along the bolt carrier)

 

remove the side locking plate from the side of the bolt carrier by puling the nozzle assembly forward a bit, till the side plate starts to tilt out of the side of the bolt carrier (then just grab the side plate and draw it forwards and out)

 

remove the nozzle assembly from the bolt carrier

 

bolt carrier is now stripped

nozzle and bolt assembly strip down

 

remove the o-ring from rear of the nozzle tube/bolt assembly

 

knock the thru pin that holds the bolt onto the nozzle tube out of the nozzle tube - start pressing it out with a small drift then when it starts to emerge form the side of the nozzle tube just grab and pull the pin all the way out using long nosed pliers (its not in that tight)

 

remove the bolt from the nozzle tube (a small flat bladed screwdriver will help to start levering them apart)

 

remove the flute valve parts and spring from inside the nozzle tube

 

nozzle and bolt assembly now stripped

 

upper receiver strip

 

remove the carry handle by loosening the two nuts and taking it off the rail on top fio the upper Stick the carry handle assembly to one side for now

 

pull back on delta ring to free the rear of the handguards

 

remove the handguards - if its the stock AGM061 handguards find a bin and throw them away lol

 

pull back on the delta ring again, now fit an armourers tool or c spanner into the barrel nut teeth and loosen the barrel nut

 

completely unscrew the barrel nut from thread on the upper receiver

 

draw the complete outer barrel assembly off of the inner barrel

 

withdraw inner barrel and hop assembly out of the upper receiver - be careful not to lose the spring that tensions the hop as you draw the hop unit out of the upper -e.g. keep a hand over the top of the assembly so the spring doesnt launch accross the room, or withdraw the hop unit from the upper very slowly and keep an eye out for the spring startign to show - its at top of the unit and near the rear of it

 

put inner barrel and hop unit to one side

 

remove the charging handle rubber buffer from insde the upper receiver - its a plug fit and just prises out

 

remove the c clip that prevents the ejection port pivot pin from coming out

 

withdraw the ejecion port cover pin out of the upper.

 

The cover and its tensioning spring should now be free to remove too.

 

With ejection port cover removed you can undo the small philips screw on it to gain access to the spring and detente that hold it in its closed position

 

Next knock the forward assist pin out from top of upper receiver downwards, using a small drift or punch of appropriate size (it helps if you depress the forward assist button while doing this)

 

with the pin out the forward assist and its spring can be removed from the upper

 

upper is now stripped

 

stripping forward assist

 

remove spring from forward assist

 

knock pin out of forward assist

 

remove the ratchet from forward assist

 

remove the small ratchet tensioning spring from inside the forward assist

 

forward assist now stripped

 

 

stripping hop unit

 

locate the oring that sits inside front of the hop unit adjuster drum (inner barrel is grooved to hold it)

 

roll that oring forwards clear of the hop adjuster drum

 

pull adjuster drrum off of the hop unit

 

seperate the hop unit into two parts - it can be tigth around the hop adjuster arm pivot point but will come apart

 

remove the adjuster arm from isnide the hop unit

 

remove inner barrel from hop unit

 

remove hop rubber from inner barrel

 

hop unit now stripped

 

 

stripping outer barrel assembly

 

undo grub screw from flash hider

 

unscrew flash hider (counter clockwise thread so turn clockwise to unscrew it)

 

remove chrome ring and oring that are behind flash hider

 

knock out the pin holding front sling mount onto the front sight block (carefully support the parts as you do so)

 

with sling mount removed loosen the grub screw hidden below it

 

knock the two pins out that hold the front sight block onto the barrel

 

slide front sight block off of the barrel

 

slide handguard end cap off of the barrel

 

slide barrel nut and delta ring assemblies off of the barrel

 

outer barrel now stripped

 

stripping front sight assembly

 

remove the front sight post from the front sight assembly by unscrewing it

 

remove front sight poste detente and spring from front sight assembly

 

front sight assembly now stripped

 

 

stripping delta ring

remove circlip from rear of delta ring assembly

 

remove weld spring from delta ring

 

delta ring assembly now stripped

 

whole rifle now stripped bar the carry handle/rear sight assembly

 

 

carry handle/rear sight assembly take down

remove the attachment nuts from carry handle

 

remove the side locking plate from carry handle

 

undo grub screw from windage adjustment knob

 

use philips head screw driver to hold the screw at opposit side of the rear sight from the knob and unscrew the windage adjustment knob

 

look out for small spring loaded bearign that acts as a detente on the windage adjustment knob

 

remove the philips head bolt from opposite side

 

sight element can now be removed watch out for the spring steel tension plate underneath it

 

remove grub screw from underside of the carry handle

 

remove the spring and small bearing that sit below that and act as the elevation adjustment knob detente

 

knock the split pin thru that sits below the elevation adjustment knob

 

turn the knob to raise the rear sight block untill both it and its adjustment screw are clear of the elevation adjuster

 

be careful to catch the tension spring thats fitted into front left hand side of the rear sight block

 

knock the threaded central pin out of the block

 

remove the elevation adjustment knob from the carry handle

 

it'll seperate into two parts

 

carry hadle assembly is now stripped

 

entire rifle now stripped, for an extra challenge find a large plastic box, put all the bits n it, close the lid and give it a good shake around :D

 

Edited by snorkelman
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Just a question out of curiousity, but:

 

Does anyone think a V-hop up would work with the PGC aeg compatible hop assembly (or its copy)?

 

I noticed that the provided hop rubber has two flaps on its side to hold it in place in the assembly, so that might be a problem and require modification to the V-hop.

 

-T.S.

 

Any AEG compatiable hop rubber won't be compatiable with this unit. The supplied one keeps the barrel in place and centred, plus the front of the supplied one is longer. It also acts as the feed ramp for the bb's and is made to mate with the nozzle.

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One thing I noticed is that there's also an e-clip on the pin that holds the full-auto sear, along with the white plastic spacer.

I noticed this cos I spent about 5 minutes thinking "why the f%@king hell won't this b&%@ard pin come out?!" while first dismantling my gun.

 

Course, that's just my gun. Sometimes seems that mine is different to all the other AGM M4s out there.

 

*EDIT*

Incidentally, I've noticed people talking about PX-Airsoft.

The url www.px-airsoft.com is just a placeholder page. What's all that about?

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One thing I noticed is that there's also an e-clip on the pin that holds the full-auto sear, along with the white plastic spacer.

I noticed this cos I spent about 5 minutes thinking "why the f%@king hell won't this b&%@ard pin come out?!" while first dismantling my gun.

 

Course, that's just my gun. Sometimes seems that mine is different to all the other AGM M4s out there.

 

aye mine had no eclip just the white spacer, I noted a little side play iinthe fit of the parts inside the lower (probably cause of lack of that e-clip) but just ended up using a gearbox shim on the opposite side to shim it out - right side of receiver|white plastic spacer|auto sear|gearbox shim|left hand side of receiver

 

I'll dig out an eclip an shove that in it next time Ive got it opended up

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Just a heads up. On Airsoft Global, they are selling replacement valves for the magazines as well as replacement bolt carrier group. Looking at it, it seems like they are all stock replacement parts.

 

There is however a steel bolt stop for $15. It should be AGM spec and would not need any further modifications.

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Just a heads up. On Airsoft Global, they are selling replacement valves for the magazines as well as replacement bolt carrier group. Looking at it, it seems like they are all stock replacement parts.

 

There is however a steel bolt stop for $15. It should be AGM spec and would not need any further modifications.

 

Ha!

 

That $15 bolt stop is nothing but the stock pot metal bolt stop, which is terrible. It even has the small hole for the steel insert where it engages the bolt carrier. If it was really steel then why would it need the hole?????

 

It also has the nasty seam line from the mold.

 

I think that part is worthless. Why would they even sell it?

 

Buy the RA-Tech $15 STEEL bolt catch instead.

 

-Luis

 

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@Bonjour43:

 

Very nice fix my friend. The little tab on mine is broken as well. I need to borrow a drill myself to do that little mod.

 

Hey no problem - I'll need even more help from you guys in the near future when I start tinkering with internal components. I'm just a total freak when it comes to the solidness of these all metal guns and it bugs the HELL out of me if something feels wobbly when it's not supposed to.

 

Anyhow, in addition to the tab mod I also had to do something to the bottom RIS plate to make it 100% wobble-free.

 

The bottom notch on the delta ring that engages the barrel nut was acutally in contact with the bottom RIS plate, so the delta ring was never able to completely push forward to tightly clamp the top and bottom RIS plates together:

3759307861_c063be2039_o.jpg

 

I drilled another small hole (1/16" drill bit again) on the bottom RIS plate where the delta ring notch is scratching/pushing against it:

3760146722_c1fa0ce3e9_o.jpg

 

So that when the delta ring pushes forward, the notch that engages the barrel nut will not be pushing against the bottom RIS plate anymore.

 

With this small mod and the one I did before to the front sight tab, I can say that my RIS is now 100% wobble-free - I can grab the gun by the RIS end and twist it left and right and there is zero movement, the way it was supposed to be when the gun was put together.

 

I think I'm satisfied with the externals now... moving onto the harder and more complicated stuff starting later this week ;)

Edited by Bonjour43ma
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Ha!

 

That $15 bolt stop is nothing but the stock pot metal bolt stop, which is terrible. It even has the small hole for the steel insert where it engages the bolt carrier. If it was really steel then why would it need the hole?????

 

well personally Id buy the RA-T part for same 15 bucks, but bear in mind that photo on their site might actually be one of the stock AGM part..

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I just looked at the photo of the AGM "steel" bolt stop. It does indeed look like a stock one. If its not the actual photo of the bolt stop they are selling, they should put one up. If it is, well...the space for the steel insert is a waste as that's just anothe 2mm that the bolt carrier will be slamming into.

 

I don't have experience with the RA-Tech bolt catch. I heard there's minimal fitting required that could be done in under 5 minutes with just sand paper. I ended up purchasing the G&P stuff (bolt stop, trigger, sear, hammer, anti rotation links). I probably could have cut the costs by purchasing ACM parts for it instead. I get my trigger parts tomorrow. Hopefully they will work just fine in my AGM M4.

 

I do hope that AGM comes out with a replacement firing block. If they come out with it, I'll purchase one. They do need upgraded output valves to replace the crappy one from the older generation AGM M 4 GBB magazines though. Since they are clones of WA magazines, I hope they make them so the seal issues can be remedied with much better parts/material.

 

----------------

 

Bonjour-

 

Have you tried fiddling around with the stock hop unit? Could you try something out for me? Could you remove the lower RIS, lock the bolt carier back using the bolt catch, then push back on the hop dial (towards the buffer tube), then push the hop unit forward (towards the barrel). Could you let me know how much (front to back) play you get with the stock hop unit/inner barrel assembly?

 

Also, it has been reported that the hop buckings have holes on them. I removed the masking tape that wrapped around my hop bucking and found that such was also the case in my hop bucking. I have since replaced my hop bucking with a G&P brand which provided a better seal than the stock one. I am not using the stock hop unit and hop bucking though.

Edited by sacairsoftsn00py
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the RA-T one really is a peice of ###### to fit, what needs removed from firing block channel is little more than you'ld need to sand if something had an extra layer or two of paint. To be honest most of the five mins would be spent comparing catch with the firing block to see where the block needs sanded, tearing and folding a bit of wet n dry to sand it with and then double checking there was no binding afterwards - the actual sanding of the block itself wouldn't amount to more than 20 seconds tops

 

Must admit if it was a choice between the two then Id rather someone flogged a steel valve knocker on its own to fit inside the existing cast firing block than a new firing block per-se, given that the valve knocker gets lot more of a pounding than the block does. At mo you can pick it up along with hammers or try your luck with the ino knoker inside the AGM block but for 5 or 6 bucks on its own it would be worth buying.

 

Wouldnt mind someone doing a nice hardended steel valve lock cam for the GHK mags too while they were at it lol. The lock itself isnt under any real stress - is just the cam on top of the mag that disengages the valve lock thats showing a wee bit of wear after the boltcarrier has run over it a couple of thousand times.

 

@sacairsoftsn00py

 

if its any use to you as a comparison I've checked the play in the 'RA-T hop unit with AGM adjuster barrel combo'

 

free play arrived at from measuring change in the width of the gap between front of the adjuster drum and the cut out in the outer barrel it sits in

 

when hop unit is pushed forward from the breech end then that gap is 1.12mm, when adjuster dial is pushed back towards the receiver gap is 1.26mm

 

so free play from one extreme to the other is 0.14mm (5 and a half thousands of an inch)

Edited by snorkelman
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Thanks for the info on your setup with regard to the front-back play on the hop unit...

 

I ended up sticking a spring behind the hop unit on mine so the hop unit always goes back to the same position it had been on the previous shot...unfortunately, I do not have a digital caliper to plug in accurate numbers.

 

I am using an Airsoft Surgeon light weight bolt carrier which is about 2mm longer than the stock bolt carrier....without movement on the hop, the back of my bolt carrier stays lodged into the back part of the lower receiver/front of the buffer tube. With the spring fix, i can push the bolt carrier forward using the forward assist so I can pop the receiver open.

 

----

 

I will post a review of the ghk mag through an agm when i receive mine some time this week

Edited by sacairsoftsn00py
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GHK mag with AGM M4 is pretty good. Chrono tests showed it had consistent output and just a little more fps then with the stock mag - (415-410 GHK; 400-405 AGM).

Only thing is you have to file some material off of the part which the mag catch engages.

They hold gas very well, left them for a two days fully loaded and tried to add more gas later and they were still full while in AGM mag was only about half full. The gas was Abbey Ultra. The cool down is far less noticeable using the GHK mag. After several bursts it is only little cold while the AGM can be used as a portable cooler unit - pop ten rounds and stick it under your combat vest in this hot summer days :)

Only let down with GHK's is their price. You can have two of those 5KU mags (please someone test them if they are skirmish worthy) for the price of one GHK

Anyone know what happend to ProWin mags?

 

Anyway, this is all testing that I could do before part of those plastic thingies around the nozzle broke off. Think I'll go with the complete NPAS BCG, and replace the hop unit and the bolt stop while at it.

 

 

Please someone post a quick review of that cheap hop up unit replacement for AEG barrels is it worth it or not.

When using a AEG barrel is the standard M4 dimension adequate or it sticks out of the flashider a bit?

 

 

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