Cyma Cm.621 Upgrades

[Misery]

haha true.yeah im thinking that but am willing to try lol,yeah i guessed that would be case,will do once my other parts arrive tomoz then can throw it back together and test,that i am now with amount of work  going into this lol

 

[RonLancs]

haha true.yeah im thinking that but am willing to try lol,yeah i guessed that would be case,will do once my other parts arrive tomoz then can throw it back together and test,that i am now with amount of work  going into this lol

It's just the way it is mate. Once you've finished this build price everything up (and be honest) and see how much it came to so when it comes to the inevitable next "forever gun" you can see if its worth upping the budget on a more pricier bit of kit i.e. CYMA Platinum... Mmm that's my next purchase. 

 

[Misery]

118 in total i spent 20 on buying the gun so 138 in new 621 is 160 i set a limit of 160 in total for upgrade parts or replacement parts from the outset as originaly was going to be buyting a new cyma when i got offered those so set my limit to the cost of said gun new including what i paid ofr it in that budget,next up is a scratch build dmr for me

well after i put motor from the 621 in my stepsons 516 and a cheap mosfet in it to then ill start buying the parts every so often for the dmr

 

[RonLancs]

118 in total i spent 20 on buying the gun so 138 in new 621 is 160 i set a limit of 160 in total for upgrade parts or replacement parts from the outset as originaly was going to be buyting a new cyma when i got offered those so set my limit to the cost of said gun new including what i paid ofr it in that budget,next up is a scratch build dmr for me

Fairs man! A DMR would be sexy but I personally just don't have enough outdoor fields near me..  I mean I could put a scope and a bipod on my MP5 and that'd be a DMR right? haha 

 

[Misery]

i iknow probs stupid throwing all that on the budget cyma but idrather that than buy new and then have that expense on top as pasrts have failed seeing how many rifs comen quite frankly dopdgy out the factory

the two i have that are in a 10 mile radius are both outside thank god so be able to use it even if i had to travel further i wouold just to use it loooool,hahaha hell yeah hahaha

edit: as dodgy as my typing it seems hahaha

 

[RonLancs]

i iknow probs stupid throwing all that on the budget cyma but idrather that than buy new and then have that expense on top as pasrts have failed seeing how many rifs comen quite frankly dopdgy out the factory

the two i have that are in a 10 mile radius are both outside thank god so be able to use it even if i had to travel further i wouold just to use it loooool,hahaha hell yeah hahaha

edit: as dodgy as my typing it seems hahaha

Yeah haha I guess I'm a metal body whore. I've held polymer rifs and they're nice and all that sturdy etc.. But i like my rifs to get weathered and scratched and dinked lol. 

 

[Misery]

haha so am i if im honest bud id rather have this as reliable as i can get it so i can throw the money into getting a really nmice metal m4 upper and lower nice long ass either keymod or skeletal style handguard,internalwise all i know is ill be getting another perun for it,will see how the 13-1 gear set and the high tourqe motor are like before deciding what ill be doing that side of things have spotted this gear box

View attachment 68777

 

[RonLancs]

haha so am i if im honest bud id rather have this as reliable as i can get it so i can throw the money into getting a really nmice metal m4 upper and lower nice long ass either keymod or skeletal style handguard,internalwise all i know is ill be getting another perun for it,will see how the 13-1 gear set and the high tourqe motor are like before deciding what ill be doing that side of things have spotted this gear box

View attachment 68777

13:1 for a DMR? Hmm, might want to look at higher ratio and a high torque motor. It'll still be snappy but with pulling a bigger spring but hey, thats a convo for a different thread.. In fact search on here and you'll find a belter I was involved in. I'd look but I'm supposed to be working right now!! haha 

 

[Misery]

haha long way off deciding what will be going in it if im honest still want to have my first skirmish haha ill look into that nearer the time,hahaha get back to work slacker

 

[Sitting Duck]

@Sitting Duck bought ptfe tape yesterday done the seal which has sorted the cmpression when nozzle isnt fitted but as soon as nozzles fitted i have very little compression,any nozzle u recomened to replace it?

Ahhhh tricky one coz the tappet is a bit bespoke

and the usual Red SHS is very loose/wobbly on it

The plastic SHS TZ0100 is a better fit - slight wobble but way less than Red M4

https://www.shs-airsoft.com/product/shs-m4-nozzle/

Trouble is - very few places stock them

and the odd slot dooberry is supposed to prevent "bb suction"

(where incoming bb plugs the nozzle and restricts cylinder filling with air

though this is more likely to occur on a full/closed cylinder than a ported one)

So this so called innovation is not needed on most/nigh on all guns

The other issue is the "slot" may - untested may, may cause turbulence

in expelling the air to hop/bb etc...

So you are unlikely to find one locally and not needed & may disturb airflow

BUT it does fit better than the Red SHS nozzle

Now a SHS Red M4 fits lovely on a SHS tappet plate

but that don't fit in Cyma box - so you gotta mod it with cut outs up front

like I mentioned a while back...

before/after...

Now you could buy a LONEX tappet plate...

But be careful....

some refer to a Lonex plate that has cut-outs like Cyma

& some refer to a Lonex that is straight edges like SHS

me thinks Lonex have revised stuff perhaps

and/or the Ultimate tappet has the cut outs now

& Lonex is straight edge - bit confusing

Lonex gearbox with Lonex tappet...

http://www.clandestineairsoft.com/bmz_cache/2/2823a11f89cd1d24f5eb8d2d4173736b.image.735x550.JPG

weird coz gearbox doesn't have the extra material inside like Cyma

so doesn't need the tappet to have cut outs in a Lonex box ???

Now here is a Lonex tappet plate also...

https://www.fire-support.co.uk/product/lonex-enhanced-tappet-plate-for-version-2-gearbox-m16g3mp5

and here is the Ultimate (ASG/LONEX linky somewhere)

https://www.fire-support.co.uk/product/ultimate-tappet-plate-for-m16g3mp5-series-version-2-gearbox

GB-01-18A & UL-PT-16618

with me thinking the tappet with cutouts is now the ASG/Ultimate one now

& Lonex tappet is now solid edge like SHS

AND -  even then I don't have a fucking clue how snug the stuff fits on them

so maybe forget the Lonex/ASG lottery if it is cut out & what nozzle will fit etc...

I think Lonex/ASG tappet is not worth it

you could buy a new cylinder head with fatter spout - so shit nozzle seals a little better

(but dunno what one to tell ya to get)

Sooooo - that leaves a SHS v2 tappet, modded slightly to work in Cyma box

and then a Red SHS nozzle to go with it - just std one

you don't need the double o-ring one

(often the double o-ring one has nicks in it to prevent bb suction

but there are some double o-rings without nicks - but most are nicks)

https://www.amazon.co.uk/SHS-Shooter-Aluminium-Double-Nozzle/dp/B013M53VQ4

So keep it simple and just go for a single o-ring

then mod the SHS tappet to fit in Cyma

Not a massive investment - more bit of time sorting it out on SHS tappet

Now Pete @ak2m4 does a few nozzles...

std...

https://www.ak2m4.co.uk/internal-parts/nozzles/ra-m4-aluminium-nozzle

double o-ring - without nicks it seems...

https://www.ak2m4.co.uk/internal-parts/nozzles/ra-m4-aluminium-nozzle-double-oring

(weird - most if not all the ones I've seen & few I have have nicks in them)

plus a ZCI one too...

https://www.ak2m4.co.uk/internal-parts/nozzles/zci-aluminum-air-seal-nozzle-v2

and a AOLS one...

https://www.ak2m4.co.uk/internal-parts/nozzles/aols-m4-aluminium-nozzle-double-oring

though this is a little longer and has nicks in...

(though dare say if filed down slightly most of nicks will vanish)

So Pete has FOUR nozzles

Hopefully ONE of them MIGHT be a more fit on Cyma std tappet

either old clear one in 516's or revised blue one in latest 517's & 621's etc...

(they both wobble with SHS Red nozzle - same shit but different polymer/ABS/Plastic)

If Pete doesn't have a Cyma weirdo bespoke tappet - I can post him one of my old clear ones

then he can try & see if one nozzle fits on std Cyma tappets better (or not)

Might find one nozzle is better - like the black plastic M4 nozzle

but the slotted one I don't think really caught on & not worth stocking

unless nothing fucking fits on Cyma tappets properly

So really - I think if you want the job done right

then you are likely looking at a £5 SHS nozzle

& a £3:50 SHS tappet to mod like Cyma one

 

[Misery]

bugger it will stick with the low compression loool im not willing to spend anymore just now haha will wait on the motor gear and bearing coming in hopefully tomoz and get her back together and leave her be lol aslong as she runs hits 320fps then shes geting left lol

wanna start buying in my face and head pro then tac so can start saving for my future build or a higher end rif lol

 

[Sitting Duck]

WTF ???

View attachment 68777

Now don't get me wrong, fancy high end shit is all well & good

if you got money falling out of your arse & all that

and some Youtuber's build hose machines almost as big as their fucking ego

and yes ultra high parts are manufactured to higher tolerances blah blah blah

and a CNC box owner will obviously say it is the best

(fucking hope so for the money you paid for it)

But there is also the classic newbie mistake of slinging in the most expensive parts

without checking how they all fit & operate together

(if you ain't checking = you ain't teching)

They sling in stfu bits n bobs - the very best/most expensive bollox

lonex gears or Seigtek for example...

sling it all in and it don't work too well or pretty piss poor

But REALLY...

pic again...

View attachment 68777

if you don't fucking know which fucking gear goes where

and you need a diagram on the cunting expensive as fuck box to tell where expensive shit goes

then you really should just send it all off to somebody else to build for you imho

fuck me - looks like IKEA are making airsoft parts now

 

[Misery]

haha i know what your saying lol nah ive looked into that box and seems not to bad was more the being able to access the gears trigger etc without having to take apart the full casing lol that drew me to it as for cost aye its expensive lol  and like i said wa one i spotted nothings definite for the future build other than asthetics in that it will be m4 based lol

 

[Sitting Duck]

bugger it will stick with the low compression loool im not willing to spend anymore just now haha will wait on the motor gear and bearing coming in hopefully tomoz and get her back together and leave her be lol aslong as she runs hits 320fps then shes geting left lol

wanna start buying in my face and head pro then tac so can start saving for my future build or a higher end rif lol

think most people look to tear down a gun once she dips below 300fps

(as a general rule of thumb - unless you are perfectionist trying to maintain constant range/performance)

nozzles will never seal 101% like say cylinder head

coz they are shuttling back n forth but unlike piston

they don't swell outwards from vents in piston head etc...

so nozzles will never seal 101% & if it is too tight on spout

that isn't ideal either for rapid shuttling back n forth

now yes it is gonna leak if it is really loose & not ideal

but you have lessened the leaky as fuck cylinder head

so though you may not reclaim say 30fps

you should perhaps see 10fps or so at least improvement

and the issue with all this shit is where do you start & where do you stop ???

I said they are a bit bespoke/qwirky - but they are pretty decent cheapo starters

just a bit less TM Compatible in some places

I mean yeah you could buy a new cylinder head that std nozzle might fit better

and also a new nozzle/tappet combo & mod it a little (pita Cyma)

But really I think your approach is right atm

maybe further down the line if fps drops or it shits the bed

then open her back up when it needs it and do the nozzle/tappet thingy perhaps

I can pm Pete about sending him a Cyma tappet to try his nozzles on

but think most of them will still be a little loose on the Cyma tappet

fucking annoying coz the Cyma v3 boxes/tappet are more compatible

it's these fucking v2's that are a little weird...

the 516 is a v2 gearbox - but uses a v3 spring guide (thicker tab at back)

the safety arm - have to remove screw before you open box

the tappet plate has the cut outs up front that most don't have

the ye olde trigger switch has a big eyelet or mod other switches to fit

and at back of switch selector it still uses prongs & copper plate on selector plate

plus it is re-enforced so need to mod box to fit 13:1's in their v2 boxes

(on v3's they go straight in coz not re-enforced - but a few v2 boxes are like this)

but they are a good strong cheapo box that won't crack easily like a G&G blow back box

& way more reliable than say a Nuprol or others with micro switches that burn out asap

I suppose the 516 is like a half decent Punto

cheap as fuck, you know it ain't high end to challenge an BMW

but if you go easy it will do ya proud to run around with

and if it really goes tits up then you cut ya loses and buy something else a bit better

 

[Adolf Hamster]

Now don't get me wrong, fancy high end shit is all well & good

if you got money falling out of your arse & all that

and some Youtuber's build hose machines almost as big as their fucking ego

and yes ultra high parts are manufactured to higher tolerances blah blah blah

and a CNC box owner will obviously say it is the best

(fucking hope so for the money you paid for it)

But there is also the classic newbie mistake of slinging in the most expensive parts

without checking how they all fit & operate together

(if you ain't checking = you ain't teching)

100% this

the real skill in teching is getting a good gun to shoot well on "inferior" (put a lot of weight on those quotation marks) parts.

unfortunately some folk make the mistake of thinking that more expensive parts=better parts when the reality is even a well-made high quality part can absolutely ruin a gun if it's not the right part for that build. for example that gearbox shell might be superbely made and exactly to spec but if that spec isn't exactly the same as the reciever it's going into then the hop might not line up, the body pins might not line up just right or the motor alignment might go out but only when you tighten down the stock screw or something along those lines.

i mean it's entirely possible to have a £2k+ gun be incapable of hitting the broad side of a barn if it's not setup correctly.

as an answer to the compression problem personally i'm a big fan of these nozzles:

https://www.ak2m4.co.uk/internal-parts/nozzles/ec-m4-metal-nozzle-double-oring-21mm

although they're out of stock at the minute.

 

[Misery]

i see what you mean @sitting duck about the weird size in nozzle its 21.6mm with an id of 5.33mm https://www.ak2m4.co.uk/internal-parts/nozzles/ra-m14-aluminium-nozzle

closest length i can find but dont know the id of it

 

[Misery]

well she is finaly finished seems to be running sweet dry firing anyway just bout to test it with some rounds

she has also cost me my 2ndry screen on my pc well more myself has put the spring in the wrong way it bound got it apart but as i did it shot through grip and hit my 2nd screen lol thank god wasnt my gaming scree lol

View attachment 69635

 

[Misery]

the 621 saga continuesok so testing today has shown that the safety latch is pretty much screwed cant use safety at all regardless of what trigger,also in semi it will shoot a few semi shots then ahoot again and get a  burst that continues for a second after i have removed my finger if switch to full auto it does auto but continues for a second or so after removing finger from trigger i did upgrade the tappet spring to a gaurder one but doubt thats causing the issue   @Sitting Duck what you reckon sorry to be a pest again bud

 

[Misery]

thats also on both 7.4's and 11.1s

thinking of reversing steps try the original motor with the gear set then if needs be revert bk to standard gears and just buy a standard set for my step son

 

[Adolf Hamster]

sounds like trigger sticking? possibly mixed in with the cutoff jammed.

over-run is a thing but never heard of a gun over-running by more than 1 round.

the safety is an easier one to diagnose as the lever is very visible in it's function when you split the box- easy enough to see if it's bent/binding/jamming on the trigger itself.