Rogerborg

Mmm. I'd normally be all caveat emptorish, but his/her/zeir only interactions here appear to be buying and selling. I'd question the value of that, especially if ze's going to be flipping prices to the moon.

Beats me. The ones we've been pointed at appear to be more expensive than ABS or PLA. It's baffling, but... airsofters.

The thing is, despite it being a phenomenally bad idea, it wasn't actually an offence, as they did have a reasonable excuse, and could presumably prove it. Flipped arsey-versey, our budding Quentin Tarantino here is legally just fine to get his hands on a RIF (assuming 18+) but I rather hope that he doesn't.

Why imagine?

Well, shows what I know. Using a cheap and admittedly uncalibrated luggage scale, with a Silverback 100 "Newton" spring with about 4 loops cut off, I'm seeing a 17kg (166N) peak from a slow, careful pull, and nearly 25kg (245N) peak from a more realistic sharp pull. It still doesn't feel anything like that, mind, because it's a short, smooth pull. Makes me want to try a Rapax 2J+ spring which claims a lighter pull for the same boing. Out of stock at Skirmshop, of course. £21 delivered from Serbia... except if I get mugged for VAT, and the mugging to pay for the VAT mugging.

If we're going to be technically correct - the best kind of correct - chronos only measure elapsed time, then calculate fps from that. Joules is just another step down the line. Let the silicon take the strain. It seems obvious, but I've yet to see it up here. Hmm, I might start laminating them and sticking them up at chrono stations, like some sort of efficiency vigilante.

Indeed, I'm all for it. "M" ratings are intended to be helpful, but given the wide range of variables (air seal, cylinder to barrel ratio, BB mass) they're really just a relative scale, and only within a manufacturer's own range. The Silverback springs just give a single Newton value - I'd assume (by which I mean hope) that it's at the compression of a fully cocked and locked SRS or TAC-41. Even at that, with a 100N spring in mine, it doesn't feel like I'm lifting 10.2kg to pull the bolt. Hmm, that would actually be measurable though... 🤔

This is nothing personal, but we have zero self-interest in helping you. This is a forum primarily for people who use airsoft guns for their intended purpose, the one behind the defence that we enjoy, and which could be removed on Ministerial whim at any time if RIFs are abused. The very fact that you asked here rather than on a theatrical forum suggests that your intentions are not what you claim.

The great thing is, you'll then get to see some real guns up close! https://www.standard.co.uk/news/london/student-filmmakers-handcuffed-by-armed-police-while-making-movie-on-streets-of-london-a4282551.html

Sadly, I rather suspect that we're going to see it relisted soon enough as "Mint condition, shoots like a laser, barely out of the box."

Or in Joules. And Silverback springs are measured in Newtons. Why can't we just all agree on a sensible value like ergs, or angstroms per femtosecond?

Maybe. But is it quicker to press a button two or three times than to look at a number, than to look at a different number, then do the finger-shuffle on a spreadsheet to find the first number? If I'd ever seen a site that had printed out just the limits for each BB weight and gun type, it would make more sense, but I've yet to see that. It's either a generic chart where they're looking up a Joules number anyway, or worse, the marshal's got something on his phone to work it out which is almost certainly slower than changing the chrono setting. Could be wrong, but it's marginal either way.

Given the currency devaluation / inflation situation, and (literally) half of China being locked in their pods at the moment, I'd only expect that to go up, sharply. They're not going to get any cheaper or more available.

Yes, it should be an M90, with a spare M120 in the box (although it may be in an opened "M90" wrapper). The M90 should be usable, and notionally an M100 should get to close to UK limits. However, it's entirely down to air seal and to some extend the BB weight you're using and whether your local sites chrono sensibly, or with 0.2g. You may be lucky and get close enough as it is, or want a 95, 100, or 105. I'd play with it first and see what it chronos at with the BBs and hop that you'll want to use, then take it from there. A cheap chronograph will save you a wasted day if you come out a bit spicy. It's easy enough to cut a spring down once you know what it's producing.

Snap. Seems fairly decent in garage testing, with a short, smooth pull. I'll also be testing next Saturday - race ya.

Er, well, yes. They're chronoing in Joules, but living in denial. There's a practical argument about it being slightly quicker, maybe, to cross reference an fps number on a chart than to change the setting on the chrono, especially if someone is using an unusual weight. My main issue is with still thinking and talking in terms of 0.2g and 350fps as a default, which is now an edge case for woodland. Thinking about it, the one weight that you probably don't need on a chrono for woodland is 0.2g. Really, how many people are still shooting that?

If the spring is loose on the guide, some heat-shrink can snug it up.

Unlikely, since I run a 1.8J DMR myself. What I'm more concerned about are people taking point blank shots with guns over (potentially way over) 1.3J because they've got it in their heads that "under 350fps" means that it's fine whether they're shooting 0.2g or 0.48g. Good. The sooner sites stop thinking and talking in term of fps, the sooner we can put this all behind us. All airsoft chronos show a Joules value. You don't need to work anything out, you just set your BB weight and look at that number. For example, I can tell you that my new TAC-41 boltie shoots at 1.8J with 0.43g BBs with the stock spring, and 2.27J with 0.43g with a 100N spring (minus 4 coils). I didn't even look at the fps value, and nor could I tell you what it might shoot at with 0.2g because it'll never, ever have anything that light in it. It's time to move on from 0.2g and fps. Join us in the future, we have flying cars and rocket boots and all sorts.

Ahoy and welcome.

Beat me to it. We need a holy war to convert fps heretics on pain of being point blanked with 0.48g from a Joule-creeping sniper that's "Only 500fps with twos, mate."

Was that not a warning sign to begin with? Seems a little "I've started dating a redheaded stripper called Tiffanii, hopefully she won't be crazy."

It should be usable enough with the stock M90 and 0.28g. The Specna rotary hop unit is pretty decent, so its effective range won't be much short of anything else out there. It just won't reach out quite as far as something tuned for bang on the site limit. However, at that extra 5-10m you're rarely going to get hits anyway. I'd run it as stock at least once to get a baseline in performance and see what the site chronograph says, then make a spring change decision based on that. It's always better to come out 0.1J under than any amount over.

If he could be turned, he would be a powerful ally.

Ahoy and welcome. Specna Arms guns typically come with 2 springs, an M90 and an M120. The M120 is too hot for a UK AEG (unless you seriously short stroke it or otherwise reduce the cylinder volume). The M90 will notionally give you ~295fps with a 0.2g BB or 0.8J, fine for CQB but well under the 1.13J limit at most sites. However, it's all down to air seal and in practice they tend to come out a bit higher, I was seeing more like 0.9J with the M90 (and with spot-on air-seal and a tightbore barrel you can get >1.1J out of an M90). A M100 spring is likely to get you closer to most UK outdoor site limits, but it's not an exact science and having a chronograph at home can avoid disappointment on site. Back to the battery. With an 11.1V and the stock motor and M90 spring in an Edge, I was getting regular double-shots on semi. The basic mosfet in the Edge guns does nothing to prevent this, it's just there for trigger protection. With the same battery and beefier motors (Big Dragon M140s) I was getting the same double shots in another M4 (M90) and a G36 (M100) This is always a risk with 11.1V and if it happens there's not much you can do except fit a half decent mosfet with active braking and/or precock. You might get lucky, you might not. tl;dr version - you probably want 7.4V, and an M100 spring.

It's nice to get answers rather than questions though. Sure, if you get a decent Specna, they're fine. Mine's been... OK, although the trigger takes a sulk sometimes. I really couldn't recommend them now.