Rogerborg

Yup, 0.2g is fine indoors, and tracers are great fun. It's just that 0.25g will likely produce a lower energy value than 0.2g due to your short barrel (with longer barrels, it tends to go the other way). I'd err on the side of over-hopping at the start of the day, because if you can see some lift on the BBs, then you can be sure that you've got at least enough hop on, and it'll bring the energy down. Our slide style hops can be prone to creeping off, if the screws aren't done up tightly. This is what your hop and barrel will look like out of the gun - there's a screw on each side holding the slide on, and if you ever have it apart, it's worth checking that they're snug (but not too snug, they're metal self tapped into plastic). The other thing you can do is to whip a small cable tie around the barrel and the end of the hop slide and pull them tightly together. You should still be able to move the slide, but it'll add some tension and help to hold it in place. Once you know exactly how you want it set up, you can put a little piece of grip-tape, a sliver of pencil eraser or something similar between the barrel and slide, then cable tie them together again to hold it very securely in place. I'd stress that none of this is necessary, it's just things that you can do if you want to have a fiddle and try to get it optimised. MP5Ks are great for CQB right out of the box, you've made a very solid choice.

Ouch, sorry for coming across as peremptory - I forgot that we've all had to figure this stuff out from the very basics at one point. You'll definitely want to get your hop dialled in before doing chronoing. When doing that, you'll want to use the BB weight that you're intending to play with on the day. 0.2g is fine for short range CQB, and especially if you're using tracers indoors. Outdoors, go as heavy as your hop can lift, and your wallet can afford. It may very well be the case that your hop unit doesn't need much pressure applied to lift 0.2g. Apologies, I don't have a dial-style hop on my MP5, I have the very short MP5K with a slide-lever unit, which is quite fussy - a tiny nudge can result in over or under hopping. Your dial may be the same, and I hear tell that they like to wind themselves off in use. What's important is to have as much range as possible to test with, so that you can see the terminal behaviour. With your 1.2J+ gun you can shoot out to a real-world 50-60m, and should be able to get a flattish trajectory for most of that. It can be tricky to see exactly how your gun is shooting when you're the one on the trigger, and having someone else standing off to the side to watch the BB trajectory can help. There are loads of opinions about ideal hop and trajectory. I personally like to see the BBs lifting just at the end of their flight so that I can be sure that I've got sufficient hop on. As in, over-hop slightly, then dial it down just a touch. Here's one I memed earlier. And as above, if you put a few hundred BBs through your gun, or leave the spring cocked for a bit, it should settle down. Chronoing with (properly hopped) 0.25g or heavier BBs should also sort you out. There's even a difference between a cold spring on its first shots of the day, and the same spring after putting a mag through it. I reckon your MP5 will be fine if you just get a little creative with it.

Looks like a Frankengun built from random uppers and lowers. But don't waste his time asking!

Yup. My MP5K with the hop set for each weight chronos at about: 0.2g = 1.05J 0.25g = 0.95J 0.28g = 0.9J

I can't see that this question was actually answered. <but-why.gif> Indoors, in CQB, fair enough. Woodland, you'll want at least 0.25g, I use 0.28g. In either case, get the hop set first, then chrono. Everybody else will be doing that, unless you have a weird site. On the bright side, this means you have a decent airseal, so rejoice. That's impressive energy out of a short barrel. I wouldn't go opening the gearbox, if only because the V3 triggers in these are a sod to get back in place. Just tap the trigger until it starts to cycle but doesn't fire, then leave it like that. If you do want to be sure about the piston position by seeing the cylinder, splitting these things isn't a huge chore. Take out the rear pins, undo the screw behind the magwell and push the pin through, take the small grub screw out of the fire selector, remove one side and pull the selector out from the other side. The receiver will then split along the dotted line. Reassembly is the opposite of removal, plus a lot of swearing as you try to get the fire selector, nozzle and hop unit lined up.

Lowered the price for this peasant-site, I see. I'd feel insulted but... well, I think he's got us pegged.

Passed on by an eagle-eyed viewer who wishes to remain anonymous. Wow, only £2000 for a wankergun shooting at 1.24J that you won't be able to use at any site (might be why he's never ever had an issue with it), and which doesn't appear to come with the one brand of magazine that it needs. [EDIT] Eddie the Eagle Eyed Viewer reckons that's £1300 worth at retail prices. I guess the extra £700 is for the peace of mind of that "never ever had an issue" cast iron guarantee about its past performance.

1000,000,0000% And magnets, magnets, magnets.

Was he on the balcony of the Iranian embassy? I ask because I reckon I've met all 60 of the blokes who were. Sure, sure, opsec, persec, nik nak paddywhack. Don't get me wrong, it's a great charity, and I hope you blow the roof off the fundraising. But anyone can (and too many do) claim to be "ex UKSF, obviously can't go into too much detail". Unless there are names and origin stores attached, eyebrows do tend to get raised after a while.

I can't imagine a practical way to measure or enforce that, which is why I suggested a ballistic lob, spray, and pray. Heh, good spot, I hadn't even noticed that. Well, now it makes "sense", although I'm surprised Novritsch hasn't got in on it.

Hmm. I'd wonder whether "matte blue" even meets the "bright blue" requirement for an IF. If you do want to match it, well, you'll need to match it, which means DIYing it as you're unlikely to find a pre-painted muzzle device of any sort in any colour other than black or brown, let alone your shade of blue. Bear in mind that we've already explained why you don't need to paint it, so this is has to be about aesthetics, right?

As above, and don't sweat it. It's a cheap part made of whatever recycled milk cartons and dildos got thrown into the melting pot that day, and subject to a lot of stress and flexing. I've not had one go yet, but I'd consider them consumables.

Great news. Nah, you're fine. As above, as long as over half of it is "bright blue" (and there's no definition of what constitutes bright) then it's still not a realistic imitation firearm. If you want to check the laws yourself: https://www.legislation.gov.uk/ukpga/2006/38/section/38 - "[the] principal colour", i.e. over half. On a strict reading, something that's 34% orange, 33% black and 33% grey would meet that definition, but I wouldn't try to get cute about it. https://www.legislation.gov.uk/uksi/2007/2606/regulation/7/made - non-realistic colours, including "bright blue". That's really all we've got to go on, and bear in mind that a lot of the "two tones" sold by retailers don't actually meet that definition, either on coverage, or on the brightness of the paint. Not a problem for us, the offence is committed by the seller. Not really a problem for you either as long as you're transporting it to or from an airsoft site, or using it there. It just won't be an issue. But please do be aware that public possession of any imitation firearm, whether realistic or a scaled down orange toy springer, is an offence under Firearms Act 1968 Section 19, and requires a positive defence of a "reasonable excuse" - i.e. taking it to or from airsoft.

That's for pulling a heavier spring. At UK AEG power levels, you won't need that, so I'd go high speed instead. I haven't used SHS stuff, I chisel every penny and use Big Dragon M140s. Optical is great if you want to set up a short pull trigger, but you've got gearbox issues as above. A Perun AB++ living outside the gearbox will give you everything else including pre-cock, burst modes and ROF limiting if you overcook it.

Nah, Roger was talking about Roger in the 3rd person, like the athletes and rappers do. Heheh. Roger... I mean I assumed the same thing the first time, and packed silicone grease under mine. It was only after thinking "Wait, what are those holes for" that I figured it out - oops. You can even drill some more if you're feeling frisky. Now I stretch o-rings over the outside of the cylinder, and heat them gently, specifically to make them loose. It's a bit hit-and-miss but now that same CYMA that I messed up has rock solid air-seal and hit 1.3J on an M100 spring using the stock CYMA gearbox and no-O-ring nozzle (and some aftermarket bits downstream of that). No need to resist, it takes most of the guesswork out of it - although guns can of course run hot and cold on the day.

Good on you for asking, but as above, you're fine to do it - and practically speaking, as long as you use it sensibly, it'll never be an issue anyway. Sorry to hear that the flash hider is glued on. You can generally use heat to deal with that, if you can get the plastic handguard away from the metal bits. Also, have you checked that it's not a grub screw holding it on? They can be hard to spot.

I've checked with him, and he says it's not a "good" way, just a way. He reckons he mostly did it because it would make Skylaar on Reddit go shouty-crackers, but it hasn't caused any problems. Any fairly heavy oil should do, through any holes that give you access to the gears, used sparingly - he just had some low fling chainsaw oil to hand.

Congrats on the working gun. You are now over qualified to post on Reddit. Hard to tell from a video, but I'd have a fiddle with the motor height and see if it'll hush down even more.

That's a tricky one, as if you luck out and get one from a decent production run at the right OEM, they can be fine, and have reasonable features for the price. But the fact that they change OEMs, QC, and their product lines more than a typical airsofter washes their socks does put a huge question mark over them. I'd say they're still worth a punt at the low end, but they can forget any aspirations of going up-market while they're pulling bait-and-switches.

Ahoy, welcome, and great choice of gun. What Lozart said, but how much is it off, and in which direction? Apologies if this is "Bro, I know" territory, but is the hop dialled in? An unhopped BB will drop rapidly, and an over-hopped one can go whanging off into the sky. MP5K hops with the forward-backwards slide adjuster can have a very small sweet spot that's hard to hit and hold. So you'll want to get the hop dialled in before even thinking about the sights. This will require a 50m+ range - not the local dogging woods! - and ideally someone to stand off to the side and observe the bb trajectory.

Er, but if you read the T&Cs of any other courier except for ParcelForce 48, you'll find the same prohibition and similar terms. I'm not sure who's being scammed here. Stuff tends to get through anyway, couriers don't seem that bothered. If your sender has been unlucky, well, that's luck, not a pattern.

So... yes, then?

Only if you contact him on Facebook to offer him the lift that he's oh-so-subtly asking for...