Adolf Hamster

as above, good to try to resist the urge for the time being, serve your time and get ukara setup so you can avoid the 2-tone menace. use the time to have a scout around, chat to folk about their pews, you'll find a lot of folk are more than happy to show off their toys. it'll give you some ideas as to what style you might want to go for. typically a lot of new starts gravitate to ar derivative guns (m4, m16 etc) but there's no rule says you can't start with an ak or an sa80 or an f2000 or whatever shape of pew takes your fancy. one thing to factor in is it's not just the gun you want to buy, but things like eyepro, decent boots (if you don't already have them), batteries, chargers etc, and wether or not you want to think about spare magazines and associated kit to carry them, or camo etc.

if the offset is the same and it's just length is the issue, then as long as there's a longer nozzle available it'd be feasible to trim it down if you know someone with the right equipment. i did it for the '42, trimmed down an sr25 nozzle to the right length, although granted much easier with a centred nozzle. highpressureairsoft is the biggest i'm aware of that's uk based, there's the likes of powair6 but they're in france. as we're talking about you can contact polarstar directly although it'd be very pricey.

yeah figured that'd be the issue, afaik p* will do a custom one although not sure if that applies to the offset variants, and regardless not a cheap solution.

i don't deny the f2 is an excellent engine, but figured it was a bit too much adjustability for the role. the offset nozzle does make a difference, done derped hard not looking it up...... (imma pretend i didn't get the rpd and rpk mixed up.....) you can get offset nozzle configs for the f2, although a narrower range of lengths.

a non-standard gearbox isn't so much of an issue. the majority of engines on the market are cylinder replacements that will drop into the space used by the original cylinder in the gun. kits tend to come with trigger replacement units which will be specific to a standard gearbox type (generally a v2 or v3) which have a pair of microswitches- one for the selector and one for the safety. however you can also get "universal" plug boards which will let you wire directly into the existing trigger contacts (although unless you wire up your own microswitch you'll lose select fire), for example this is how i wired up the mg42. nozzle length will be another factor, there'll be a range of different options but if you can't get one that suits you might have to get a longer variant and have it machined down yourself. take a look at high pressure airsoft, they have a range of different engines (although admittedly stock doesn't look so good these days). i'd suggest going wolverine over the polarstar jack/F1 offerings- those 2 are open bolt designs and not good for accuracy. the f2 is a great engine but overkill for a support gun role (unless you're factoring in that you might want to switch to a different gun/role in the long run)

considering my memory of a&k default hop units is trying to get them to stay where you set them, i'm still calling it a feature. to me it sounds like not that big a deal, but some folk might put a bit more store in being able to pull the barrel.

issue number 1 doesn't really sound that bad? if all that we're talking about is it's just a bit stiff to adjust then frankly that's just saying it won't back out mid-game, which i'd consider to be more feature than bug issue number 2 i'm guessing means the quick release barrel isn't so quick to release? but if it's otherwise solid (ie not rattling around) then not too bad either. a quick scout of the classifieds seems to suggest these are going more for the £200 range

i mean o rings between the front of the hop (around the inner barrel) to push the hop unit back from the upper (and by the inverse push the upper forward from the hop unit) it's the same tactic you'd use in most guns to ensure the hop is tight to the box so you get a more consistent seal.

don't really think there's a particular term for it, it's just a partial overspin. when the cutoff lever trips, and assuming there's no active braking from a mosfet, the motor just shuts off but the mass of the rotating parts, the gears etc are still spinning so they just keep rolling until something stops them, which will be a combination of natural friction, the strength of the magnets in the motor (eg a strong neodynium motor will slow down quicker) and, when it hits the piston again, the energy to pull back the spring. overspin usually isn't commented on unless you have a fast enough setup that it can not only pull the piston back a little, but all the way to roll over to a second shot (which is the double tap). as mentioned it's the same effect as you're intentionally trying to acheive if you're using a mosfet with precocking, which will run the motor intentionally a little longer so when it stops it's nearly all the way back, idea being the time between pulling the trigger and the shot actually firing is much shorter without the need to have a really fast motor/gear combo. it's genuinely nothing to worry about, indeed depending on the setup you actually want it to happen a little bit, as if you stopped the motor too quickly (eg by using active brake) then it can stop quick enough to have the cutoff lever still engaged and lockup the trigger.

you mean the gearbox noise? if it's gear noise then shimming and particularly motor engagement sounds like the culprit. assuming you've done the usual static checks to ensure the piston/piston head/nozzle is sealing good then nozzle-hop is usually then the culprit. check your hop unit positioning, typical for AR pattern guns to have a little play between the gearbox and outer barrel when assembled, a spring or o-rings around the outer barrel in front of the hop unit will push it tight to the gearbox and ensure it's in the right place, after that then looking at the nozzle length/hop rubber feedlips would be the usual suspects.

a dropped fps sounds very much an air seal issue. did you check the seal between the nozzle and the hop? if there's enough play for the hop to move forward/back then it can end up leaking there which would give a leak even if the box seems fine on a static test. one solution is the inclusion of a spring (or o-rings) to push the hop unit back tight to the gearbox.

it's a pretty common thing for different sights to have different levels of tinting to them, especially with the cheap replica stuff you get in airsoft. replica eotechs seem particularly prone to this. can't remember what brand mine was (i wanna say WE? although god knows who the oem was) didn't have as much tint as others i've seen, although the downside was that the reticle would be pretty easily washed out in bright daylight.

so issue number 1 is very common, and not really an issue per-say. essentially the motor and geartrain still has momentum when the cutoff lever trips and will roll round until stopped. it's basically free precocking, as all precocking does is intentionally run the motor a little longer so it stops near the end of travel. a mosfet with active braking will remedy this (although sometimes can go too far and stop the system too quickly giving lockups on semi), a better solution would be a mosfet with precocking which will let you intentionally control where the box stops. issue number 2 i'd say is happening because you're testing it outside of the reciever (going by the picture), assuming this is going to an ar derivative (the sr-15 in your profile) then when you put the gearbox into the reciever and bolt on the buffer tube/stock, the bolt that threads into the back of the box will go into the spring guide and hold it tight to the back of the box, stopping it from tilting.

i have had this before, guns that would barely spit out bb's at chrono only after a couple dozen shots spend the rest of the day exactly on point (i've also had the inverse- guns that would chrono perfectly then proceed to fall flat on their face the moment there was an actual target to shoot at) one possibility is gearbox alignment, if the nozzle is scraping the hop such that it'll stick the first few times then be ok. although this should be evident by any wear patterns on the nozzle.

depressing the trigger slowly sounds like you're getting far enough to trip the contacts, but not far enough for the cutoff lever arm to engage and kick it out.

i always thought it was a mix of propane and butane, more propane there is (as a relative %) the higher the pressure. although i don't really have any factual basis to back that up.

Try some o rings to space the hop unit against the gearbox, not too many though as you dont want to put too much load on the hop

i forget that folk actually put protectors on their lenses. unless it's a simple case of popping in a disc of polycarb into the existing housing i just run them plain and accept that at some point they're gonna get shot out. in fairness, i've only lost 2 optics to hits, one was funnily enough option 2 during a night game (had the thing for years before it took an unlucky hit) and the other was a repro eotech took a bb as i was shooting out a window (again after being used for years)

ran one of them on a jg ak for a long time, no parallax but it's still impressive that they can put together a usable sight for £15.

i take it the mosfet addition is something you've wired up yourself? a common cause of semi lockups can be when a mosfet is applying an active brake effect to a build that doesn't need it, stopping the system too quickly before the cutoff lever has been properly disengaged. However my electrical knowledge is limited to the simplicity of plain dc wiring and getting an off-the shelf product to do the magical silicone based shenanigans, so i can't say if your setup is doing that or not.

i feel for ya man, that really sounds like it sucks. hmm, there's an aug-m4 adapter on thingiverse and an m4-mp5 adapter. assuming they've got the measurements correct could merge them together to get what's needed *fires up cad*

i'm impressed you can read the dates of events and inferr correlations from a chart with no date axis.

yeah paintball being legal but airsoft not being is an odd one, i mean a paintball gun is a tad more potent a projectile launcher than anything airsoft can put out. guess maybe it's the ol "omg gunz r scary" approach. hmm, i'd been assuming the bent ones were needed. *goes off to do more googling* if it's just a 3-D printed adapter maybe easier to see about getting one printed that can take the curved mags if you can get those?

so you can only import the shells? not gonna lie, that's some messed up restrictions, and here we are thinking brexit was bad. going by the link i'm assuming you're talking cyma mp5 mags like these: https://www.patrolbase.co.uk/cyma-130rnd-airsoft-mid-cap-magazine-for-smg-5? edit: some cursory googling seems to suggest finding a bunch of mp5 mags in stock in the uk might be a challenge in and of itself......