Pu7z  

You could use alumina (Al2O3) ceramic bearings for that weight, but they're even costlier than ZRO2s.

From my experience, the extra cost is not worthy, since at longer ranges simply missing the shot is easier, and for the J required to sling that bb at the required range the gun gets louder, and a well tuned r-hop is a necessity.

Lately I found that using .48g ammo at a lower J is cheaper, quieter and easier to setup a gun for. And I don't have to worry as much for my MED.

I did make a kill from a single shot at 116m once though, but it was lucky to a point.

mwrose777  

I'm torn on the subject here. As Masada mentioned, we've been toying around with ceramic BBs, I bought some of the HPA .68s (really .66s) and he has some of the .69s that I bought from Careful, and some he sourced himself from China.

My R-hopped SRS (3.3j with a .32) can not lift the careful .69s for whatever reason. But it fires HPA .48s so great I doesn't matter to me. I have not tried the HPA .68s in it, or Masada's china .69s.

My SSG24 (3.4j with a .32) appears to possibly be able to hop the HPA .68s, but I need some more test time and more room. I was limited to about 93 yards. I have not tried the careful .69s or the china .69s in it yet, but it also fires HPA .48s fantastically, so I'm not too concerned about the heavier bbs (though IF it can fire them, I'd like to have the option)

For me personally, cost is not too much of a factor. I don't play that much, so I don't shoot that much. (After attending my first game at Fort Hood a few years back, local games just don't do it for me anymore). So I MIGHT shoot 100 bbs in 6 months. I'm perfectly fine spending the extra $$$ on ammo if it's going to give me a competitive advantage. I've seen Masada's custom VSR outreach any other airsoft gun I've laid eyes on, to me that's a competitive advantage. I realize other people have different situations or maybe go through more rounds in a given period of time, so cost WOULD be a major factor. Different strokes for different folks.

MagicMarker  

I can't say directly yet, without a bunch of range data, but I've observed the following:
- Novritsch .49g BBs (actually .48g) perform noticeably worse than BLS .48g BBs
- The above was predicted by my data
- BLS .48g BBs got me to 106m up-hill without much holdover
- Those shots taken above degraded in consistency larger than a human torso (in terms of 100% hit rate)
- The performance gap between Novritsch .48s and BLS .48s predicted by my data is smaller than between BLS .48s and G10 .69s
For the reasons above, I currently firmly believe that normal plastic BBs have room to improve (haven't hit an intrinsic wall regarding our ammunition format), and that the G10 .69s will perform noticeably better than anything else.

Si3N4 appears to be what BB Bastard used for their .36g NITE BB.

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Pu7z  

Yes, Si3N4 should be around that weight, but, they're black. Alumina is an ivory white.


Anyway, for a 10x higher price per shot, I don't think you'll even get a 50% better shot to shot consistency using ceramics. The added weight of the ZRO2 bbs helps against wind at least.

But a PVC vs Ceramic of the same weight won't see much improvement I think, maybe you'll jump from a 6/10 shots on target to 8/10, in good conditions.

MagicMarker  

I mean 50% would be an enormous improvement- that's more than I'd expect. But also considering a certain someone was able to observe a difference between G10 and G100 .69s...I'd be blown away if the difference between ceramic and plastic at any weight wasn't clear as day.
Buuut I hate talk and only care about hard science. I'd like to at least get a basic test on the books ASAP, however I'm saving my Nites for the formal indoor testing, and they're going to be a pain to track as well; currently looking for some G10 Al2O3 in 5.95mm (maybe 6mm if necessary)...

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wyz2285  

Sorry for not contributing anything useful, just some personal opinions.
For the energy you guys are launching these lil bombs... I'd hate to come across any of you at field. Unless your guns have range finder sights and is unable to fire if below MEDs. One step further you guys are better off playing with pellet guns...

mwrose777  

I do carry a laser range finder. And even with a 100’ MED, I rarely shoot under 200’, I have team mates that play as riflemen or saw gunners for that. I’d rather be shot at range with a high FPS gun than 10’ from an AEG any day of the week.

MagicMarker  

I know this might not be directed at me per se, but fun fact: I may push the hardest out of anyone for ceramic acceptance with motives to push the limits of range and accuracy, but actually, 90% of enemies I spot at the 4 fields I frequent are actually in range of a .48g BB at 2.5J with a nearly flat trajectory- in fact in plenty of scenarios, loading such heavy ammunition would just allow my enemies to dodge the shots easier without much benefit.
I don't know if I fully understand your concern though. Don't the fields you play at employ MEDs for higher powers? Obviously no one wants to be hit with too much energy.

Also, I got those 5.95mm Al2O3 BBs...except I didn't, they sent ZrO2
They're out of stock apparently; I reached out and they're sending 6mm Al2O3s now...

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1tonne  

It may been ludicrous but I also wonder if done right, that ceramics and even metal can be safe. This would mean an MED of a certain range.
What is the difference in a plastic bb hitting you at 3.3 joules and a ceramic bb hitting you at 3.3 joules

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Masada  

The one or two times I play each year are generally at large games with large fields. Most of my encounters end up being at minimum 80-90 yards with maximums as far as you'd like. There's a real benefit to a heavier bb for me. This is also probably why we are allowed 3.6J for bolt guns too.

At the same velocity and same energy level there is no difference. Realistically, the ceramic will be the heavier bb, thus less velocity, and should actually do less harm than the higher velocity plastic bb.

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Fynn64  

While I don`t think there would be a difference when they hit your arm for example, there is a differnence when they hit harder objects, such as windows, glasses/goggles or maybe even teeth.
A plastic BB would shatter much easier than a ceramic/steel bb.
So on those objects a ceramic/steel bb would to more damage.

If I remember correctly, how much harm it does depends on the energy, so fps and BB weight.
So it doesn´t matter if you shoot a heavy bb at low fps, or a light bb at high fps.
As long as the impact energy is the same, the harm will be the same.

Masada  

Safety glasses and goggles are designed specifically to not be hard and brittle, but to flex upon impact. That's how they stay in one piece. But yes, the harder bb would theoretically have a higher chance of cracking other very hard objects. I just don't think it would realistically make enough of a difference to notice. Plastic bbs are already very hard. I believe MagicMarker has data on this posted somewhere.

Pure energy level is not the only thing that matters in an impact situation, but also how quickly that energy is transfered to the impacted object. This is exactly how any vehicle safety mechanism works. It's not lowering the overall energy, but prolonging how long it takes to be transfered. With that in mind, I am under the impression that a slower moving object has a higher chance to transfer it's energy over a longer period of time. I know it's not as simple as that as it also depends on the type of object being impacted, but I would think that this theory applies. If someone wants to do some impulse and instantaneous force calculations that would probably help here.

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Fynn64  

True, proper eyewear will flex, not break.
Sadly there are still some people who wear crappy eyewear...

Hmm, now that you’ve said it, it seems logical that it does matter how quickly the energy got transferred.

But:
Heavy bbs don’t get slowed down as fast when fired through the air, because of higher inertia than lighter
bbs.
So I would say that they are also slowed down less, when impacting on the human body , than lighter bbs.
This would mean that a heavier bb would do more harm.

Overall though I think these differences are very marginal, and we probably won’t notice them.

MagicMarker  

It's actually a really interesting discussion to me for all these reasons- there's also the notion that our hypothetical rifles are probably firing the two BBs at the same muzzle energy, which would mean the heavier BB would actually have a non-trivial amount more energy at essentially all distances from the muzzle when it impacts because heavier BBs retain their energy better...
But in the end, I agree:
I think it's relatively safe to say, in terms of safety, BB weight and speed individually aren't worth taking into account on top of energy alone, because fields probably would have realized that by now. Chrono-ing in joules is sufficient- and even that ONE calculation based on speed and weight is already too hard for some fields! Lol.
And besides - zooming back out to 1tonne's question ("What is the difference in a plastic bb hitting you at 3.3 joules and a ceramic bb hitting you at 3.3 joules?") - we would want to assume the same BB weight and impact energy for that anyway.
Hey I'll have my girlfriend shoot me with various plastics/ceramics of the same weight and we'll see if I can guess which shots are with which material- that'd make for an entertaining little "study"

Oh and
yeah this is a serious concern- not really specifically regarding ceramic, but because average plastic BBs can destroy some of the garbage on the market...
I just saw someone at a field with the thinnest, finest mesh I've ever seen- damn near looked like mosquito net...come to think of it, I really honestly should have said something to him.

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Pu7z  

Back when I first got the ceramics, the very first test I did was to make sure I wouldn't get someone blind.

Shot at ANSI rated glasses, point blank, 3.9J at the muzzle, close to 90 degrees. Not even a crack.

Provided you use proper eye protection and don't run around smiling at shots, I think that's safe enough.