Adolf Hamster

agree, there seems to be this mythos that bad shimming=anything other than absolutely zero ability for any gear to move sideways ever not even 0.000000000000001nm but the reality is that as long as the gears can't move to a position where they interfere with themselves/other components and the bevel is in about the right place for the pinion then that's good enough. and you're right that whilst the people who build our toys might not put the care and attention into it that we do, but doing nothing but assemble gearboxes every single day they are at least pretty proficient, and they have to do at least an acceptable job to avoid returns. a basic mosfet won't, but the more advanced ones (gate warfet, perun ab++, gate aster/titan and perun optical) can do precocking, which does exactly that.

for the most pews i'd say that the overwhelming proportion of reliability issues stem from 2 primary causes: 1. mistakes in assembly, most often caused by the person doing it being inexperienced (been there, done that, still have my collection of stripped pistons) 2. attempting to push unrealistic performance, most commonly trying to push the rate of fire too hard (also been there, done that, it's about half my collection of stripped pistons) the easiest way to avoid both of these issues is simply don't fuck with a working gun. there is one exception to this rule and that's mosfets, without any kind of mosfet on an aeg over time the contacts will either carbon up, or with a powerful enough battery burn out. a simple basic mosfet (i generally use the nanoasr for this purpose, other mosfets are available) will remedy this for the long term. now granted certain guns can have very specific points of failure, notably weak parts or bad design choices etc, but it's still easier to wait until it breaks for sure before messing with it. one thing to bear in mind is that strengthened parts (eg: steel rack pistons) can have indirect consequences, where a plastic piston might wear-into it's preferred aoe or strip when overloaded a stronger part can push that elsewhere so instead of a stripped piston you might find the bevel eats itself instead.

to echo above the first thing you're gonna want is a chrono if you're going to be messing around with springs etc. not only can it check the power is correct, but it's a good measurement for consistency and wether or not any remedial work done to the air seal has actually helped. on the subject of which for range/accuracy you're gonna want to look at the following (in order of difficulty-performance ratio): 1. clean the barrel, and get into the habit of cleaning it regularly. a good rule of thumb is before every game day although sometimes even during a game day might be necessary (especially with a tighter bore) 2. feed it good quality heavier ammo, even the best gun in the world will shoot like shit if you stuff some bulldog 0.12's in it. how heavy is a toss up between your usual round count and your bank balance but generally the 0.28-0.32g range tends to be a good compromise for assault style play. 3. tying into 2 is to look at the hop, doesn't need to be difficult just a drop-in setup like the maple leaf macaron+omega nub combo when installed properly will help spin up the heavies. the longer feedlips can occasionally cause feeding issues in some guns and for those i'm a fan of the pdi w-hop with standard nub (although that'll struggle with really heavy ammo). 4. consistency- you'll need a chrono for this. you want to be addressing any potential leak so that every last molecule in the cylinder is going nowhere but down the barrel propelling the bb. the way to check this is to chrono a few shots and semi and see what sort of range of values you get, the smaller this range the better. this involves cracking open the gearbox too so a big step up in the difficulty. 5. energy- this is where you've jumped ahead to already, but the reason to wait until you're sure the air seal is good is you want to be sure the spring your using is only as strong as it needs to be to get the energy you need. if you have a bad leak and compensate with an overpowered spring you're just loading the box unnecessarily and with less resistance the piston slapping home isn't going to be happy. you don't need to be too exact, being a few fps under the limit won't be a massive loss in range but it might make the difference if the battered to crap filled with shattered nuprol bb's and soaked in mildew from sitting in a shed site chrono doesn't read so precise any more. 6. barrel- at this point the rest of the system should be getting good enough to justify a better barrel, gains aren't likely to be massive here (we're getting to the steep bit of the diminishing returns curve) but something like the ZCI 6.02 stainless barrels are cracking value for money. length wise just stick with the same length as stock, extending the barrel length won't help performance and indeed can actually make things worse if it starts under-voluming the system. worth noting whilst i'm using the conventional "fps" terminology, that's actually "fps equivalent for a 0.2g bb", when using heavier ammo the raw fps number the chrono spits out will be lower, but don't be fooled into thinking that means less range, the energy (aka joules) is what matters (for site compliance) and even if it's travelling slower heavier ammo at the same energy does travel further (among other advantages). as for semi-auto response, these days that's easier than ever thanks to the abundance of mosfets with precocking. that'll take a lot of the perceived delay out of the equation without messing with rate of fire in auto (and the potential problems driving a gearbox too fast can have). pair that with a decent motor (warhead brushless being the current kings for pickup speed, although they're not exactly cheap) and you're pretty much there already.

Dry fires sound like dn/dr, cant remember which is the opening one (the manual should clarify, i wanna say dn is opening delay and dr is closing delay) but increase that a tad might help feeding issues.

true, this is how i usually deal with it. selling secondhand in airsoft you're already tanking such a loss just from the way the market works what's a few extra £ on fees for a safe transaction.

starting to remember part of where my affinity for the ak platform came from......

whilst i can get that it's a potential pressure tactic, it can also be viewed as a case of him letting you know there's competition and if you really want it then make your decision quickly. it may not be the most diplomatic wording, but i don't really see anything wrong with that. hell i've made mention myself if an item has demand and someone wants to wait a few days before paying, if only to be clear that i deal entirely first come first serve.

^what 'borg said

it can be the case that you can do X on a fully wound mag, but Y on an empty mag. the issue i had when messing with this was i was running low pressures to be in the fps limit and on the first half dozen or so rounds in a midcap it couldn't feed. but a redneck low-flow mod fixed that issue.

pretty much it might be the case that there are feeding issues before you hit the max theoretical rf setting, depends on the mag/ammo.

ease of fitting. it depends on the particular optic, some it's not too difficult to press/glue/blu-tac an acrylic disc into the existing housing to act as a sacrificial protector with no asthetic issues. the rail mounted options are easy and work for sights where doing the above isn't easy/possible. some folks (hello) really dislike the external protectors, and if they can't do a subtle method of protection just run without and accept that the occasional broken optic is gonna be a thing. that said i've so far only had 2 optics lost to getting shot out so far and both of them were amazon specials.

you set the dp in semiauto as @Steveocee says by decreasing incrementally until you get a drop in energy, then switch to auto and do the same process for increasing rf incrementally. worth noting this should be done on your in-game ammo and in-game pressures, and if you significantly change your ammo weight on a regular basis then you'll need to do it again to get it set optimally.

rf and dp are related. dp set to its most effecient will place a hard limit on the rate of fire you can get before loss of performance as it's essentially time per shot. in an engine like the f2 the dp (and other) settings override the rf setting, so if rf is set higher than the system times your final rate of fire is however fast the rest of the system timings dictate. on the jack it's the other way round, rf can overrule dp, so if your optimum dp is slower than the rf setting allows then your going to be under-volumed on auto (similar to an aeg when it gets a mild case of pme) the way to tune this is to set the rf setting same as you set dp, only with bursts of auto instead of single shots. however there's an even easier way to tune it- set it to 25rps, that way you're not "that guy" with the bb hoze.....

trying to haggle an offer is fine, and £28 doesn't seem to be an insultingly low value imo.- not an asshole likewise refusing offers isn't really an issue. -not an asshole agreeing to original pricing because you still want it is fine too. -not an asshole putting paypal fee's on top of a listed price. -it shoulda been part of the listed price or at least made clear one way or the other, so kinda an asshole maybe but not in a big way. leaving feedback on a sale that didn't go through? - sorry but that's an asshole move tit for tat feedback- you attack someone can't blame em for responding. overall verdict- seller should have simply included paypal fee's in original price (or at least been clear on what the deal was). any time i list a posted price that is the all-in and if i get a few £ less than that because of paypal fees well that's the cost of a safe payment service you can use with random internet strangers. however you should have just walked away and called it at that. i'll be honest, i'd have just paid the fees. indeed i have done it voluntarily when an ad asks for f&f i just pay goods and services with a little extra to cover the fees, i think of it as insurance should something go south.

i'd be hesitant about shortening the nozzle, if this were a drop-in engine in a donor chassis then yes nozzle length is a thing to worry about but as this is an all-in one platform we should be able to assume the nozzle is the correct length. feels like it's an issue with how it's been assembled, but exactly what i don't know.

iirc last time i had an offer i just sent them a pm to have a more conventional dialogue and closed the sale that way. tbh, i'm not really sure on the whole site-organization of things like offers, postage etc as it's kinda making the site a part of the transaction but not really as it's still just between 2 individuals. that said, i'm not exactly doing a lot of buying/selling so it doesn't really matter all that much to me.

sub-optimal air seal is something i'd expect on a lot of new guns to some extent let alone a secondhand gun. tbh i'd say a secondhand pew showing up with perfect airseal would be more noteworthy. same with wobble, ar derivatives between the upper and lower or ak frontends getting loose are pretty typical. hard to be more exact without knowing exactly what type of gun it was.

Taking what you've put at face value: You sold a gun, with known faults which the buyer was happy to accept They then either used, or immediately dissassembled it and found/possibly caused a broken part Despite the usual caveat emptor of second hand sales you offered a partial refund, which they refused. If it were me i'd say no to a full refund. Its an understood part of buying secondhand that any pew can have hidden gremlins that even a honest seller might not be aware of, hell even face to face sales where you can test a gun is no guarantee. Some people aren't happy buying something with potential faults and no comeback and choose to avoid secondhand sales for that exact reason.

if you're gonna try shimming if you start out over-shimming, then drop it down until you get decent air seal? that way the nozzle is too far back rather than too far forward. kinda the opposite of trimming a nozzle where you shorten in little increments to be sure not to take too much off. that is, assuming there isn't some trick to the system that we don't know.

those torn lips will absolutely ruin the consistency, tbh i'm almost surprised it's not worse than it is. if it's tearing the lips like that then something mustn't be right, and nozzle as you're already thinking seems like the likely culprit, maybe going too far forward?

in that case your usual ammo weight for an assault gun would be a good pick if that's how you're gonna be using it, but if you wanna try heavier than why not. just a maple leaf macaron (green)+ omega nub, not particularly exotic, and bearing in mind that's at 1j. ofc you had to get all your firing done in the morning if you wanted to make hits in the afternoon..... even used to run them in the makarov at ~0.7-0.75j and it'd lift them. range was hilarious but given i can't shoot pistols for shit it was kinda pointless, especially as it had a habit of bulging nozzles so i stopped using them.

i'm probably the wrong person to be responding to this but as heavy as you can get, then fit a maple leaf setup to get it to lift it...... jokes aside, as with all things it's a cost versus performance balance, and it's up to you. whilst i have fed a polarstar .48's and it was hilarious the little "ker-ching" noise every time you pull the trigger is an incessant reminder of how much money is going downrange so run whatever you think has the right balance for you. one thing you need to be careful with on an hpa setup is joule creep, you want to be sure you're setting your pressures/dwell etc to the ammo you're using in-game and not anything lighter.

that'd do quite literally the opposite, there's no tactile break with an optical trigger

i'll be honest, i don't think i've ever seen this happen, at least not in a way that was noteworthy. tbh, if i thought about it i'd say drop it, because i can imagine that'd be an amusing way to frag your own team. although that said, if you dropped it i doubt any team mates would take it judging by the prevalance of people assuming freindly fire doesnt count regardless of the site's policy.

np man, at least now you know what the limitations are for the jack