A study in airsoft ammunition (primarily BB Bastards)
 

Last month I started rebuilding my CA M24 with different parts (thanks Dracheous) and have since been trying to milk the best combination out of it since, as well as huge amounts of fine tweaking, shooting and chronying (my new F1 Chrony, the standard of airsoft games) and I've also used BB Bastards pretty much all year 2007 (0.28g BBs, increased brush penetration over 0.25g!!!!) and during my diagnostics on my M24, I started recording info I'd get (about 1/4 of the time). Since Scarecrow, the head Bastard, gave me and a very few select others, his new batch of 0.30g BBs (bag each of 1000 BBs) to test out, I've actually taken it further than I thought I would, as you'll see.

This is a review, but largely a huge pile of info (aka. make this a sticky somewhere)regarding BBs we use in games, why BBs react in different ways and where quality lies in which brands and such. While Scarecrow has supplied me with a bag of each, 0.20g, 0.25g, 0.28g, and his new 0.30g Little Bastards to support my diagnostics as well as help him understand his products (ways to make better or keep as they are), I'm wanting to test other brands of BBs as well, no matter the weight (as long as in the catagory of the above that he sells) to cross reference and compare the Bastards to what else is out there. *****If anyone wants to help me in this, and are willing to donate a small amount of BBs that you use, PM me for my address, all I ask is a bag of 50-100 BBs be dropped in an envelope and sent via a postage stamp (if a full bag, I'll pay Xpress Post shipping).

Anyways, I'll start by posting my post from my first test, velocity droppage vs. increase in BB weight, then add more with a new post (will edit in some areas, but want to keep bringing this to people attention, because it's useful to everyone).

Oh ya, figured I'd say, I'm running my tests with my CA M24 (mind of it's own for velocity on any given night) and my uber consistant TM MK23 springer. All tests are done (unless specified) in my basement, if shots are taken at a target posted, it's at 30ft measured (1" at 30ft could be 12" or more at 100ft in case you are wondering).

Ok, here's the new stuff, first part is cutting open three BBs of each weight to take a pic.

http://photos-c.ak.facebook.com/phot...75382_6124.jpg

Notice that the lighter BBs have a larger bubble (or two) inside them, and the heavier ones the bubble either gets smaller or dissipates into dozens of tiny ones. Is because more material is packed into the BB. Bubbles (large ones anyways) are bad to have in BBs, mainly because they often rarely sit in the middle, causing a slight wobbling of the BB in flight as it spins (hop up). This is one reason, besides the effects of the variable air density which will cause yawing (moving the BB to the side), or causing the lift generated by hop up to cause a rolling action to one side to occur on the BB (pilots can understand that, if one wing generates more lift than the other, the plane will roll towards the side that has less lift), and because of that 0.20g BBs should never be used outdoors.

Next is some pics of targets I shot on two different nights this week, with my CA M24 using 0.30g Bastards, and a clean barrel dry swab run through before testing, and chronying after. Notice how it decides how it's gonna shoot based upon the night. Both targets were five shots each bull, aiming dead center, bench rested.

http://photos-d.ak.facebook.com/phot...75383_6542.jpg

http://photos-a.ak.facebook.com/phot...75384_6897.jpg

great info. i have a question regarding Bastard BB's. im getting a TM M14. While i keep it stock, should i use .25 bastards or .28s? that being said, i do play outdoors.

This is good stuff, i bought my first sniper tonight, and am eagerly waiting to see what the summer season will bring, keep up the good work stalker, Ill be keeping an eye out for your posts!

Flat out, 0.28g, more accurate, greater effective range, better brush penetration and more resistive to air density changes.

Am composing my chrony results from tonight's batch of testing run through my MK23 springer as I reply to your question. ;)

Next is chrony results from my MK23 springer, 10 shots of each BB weight tested. Quite interesting if you ask me! (I'll add that two nights ago I WASHED my 0.30g Bastards in dishsoap and warm water.......... including the bag. Why? Hop up puts a backspin on BBs by friction, and if each BB has a slight oily coating on it........all do, be it oil or graphite....... that reduces the amount of friction the hop up rubber can put on the BB, making you dial in more hop up to counter act it, putting a larger mass of obstruction into the BBs path down the barrel. This causes more inconsistancy and less accuracy. Mind you, I don't overly recommend this for AEG use, only bolt action will benefit from this, but I'd like to hear from AEG users that are willing to run dry BBs through their guns what they think. I've posted the BB washing thing on the Snipers Perch at www.airsoftretreat.com last year, and LOTS of bolt action users have found increased performance from washing their BBs. Nutshell, washed BBs allow you to run at lower hop up settings, reducing the 'blockage' of the BB's path, increasing everything including fps by a bit).

Ok, here's my results form tonight, chronying my TM MK23 springer with all the little Bastards.

0.20g

215.0
217.6
219.4
216.9
211.2
219.9
218.4
217.2
217.1
216.2

Mean: 216.9fps
Variance: 8.7fps

0.25g

198.3
199.1
198.8
201.1
199.1
199.5
201.0
197.6
201.0
201.0

Mean: 199.7fps
Variance: 3.5fps

0.28g

182.2
181.9
182.8
183.2
179.6
182.8
181.2
181.1
181.9
180.3

Mean: 181fps
Variance: 3.6fps

0.30g

183.0
178.7
180.3
181.7
180.9
181.4
179.3
181.0
181.7
181.7

Mean: 181.0
Variance: 3.7fps

Droppage, we have:

17.2fps decrease in velocity for a 0.05g increase in weight from 0.20g to 0.25g

18.0fps decrease in velocity for a 0.03g crease from 0.25g to 0.28g

and what confuses me, a 0.7fps decrease in velocity for a 0.02g increase from 0.28g to 0.30g, kinda shuts down (in this case) my rough rule of thumb:

"Estimate roughly a 10fps decrease in velocity for every 0.02g increase in BB weight." At least it works for AEGs, I assume because of the variable hop up unit. My springer has a fixed hop up unit that you can't set for BB weight changes.

As you can see, the consistancy between all the BBs fired through the most consistant gun I have is very tight, more so between the 0.25g and the 0.30g, less than 4fps difference which is extrememly damned good! Scarecrow has an extremely impressive product here!!! If he can get airsoft snipers across the continent (and beyond I'd like to see) 0.33g or 0.34g BBs as consistant as this, he will corner an almost non-existing market and will make tonnes of cash (I hope he shares ;) ) In a lot of cases, 0.36g are only made by Straight, and really suck for size and consistancy between them, often varying by 0.1mm in some samples I've seen measured. And heavy BBs are crutial for long range shots with 'field limit' guns (between 450fps and 550fps with 0.20g BBs), and even more so if there is any wind at all.

So when does production start on 8mm's? Cause my mossberg is thirsty.

Wow Stalker, friggin good information.
I'll be switching to .28 bastards as soon as my 25s run out.

Also, please don't take this as shitting on your work, but deviation (or at least error on your average) is the highest measurement minus the lowest, divided by the number of measurements when you have 10 or less shots per condition. The actual formula is a bit more complicated, but that's a reasonable approximation.

Like I offered once before, if you want a hand doing data analysis, including generating equations (more accurate than excel can do) and simulating different variables, I have been doing a lot of this in labs and a data course, and to a point, enjoy doing some of it.

Thanks man. Still looking where I put the word deviation in my posts though (EDIT, found them in the post I did last year, oh well). Lol

Honestly I hate formulas and equations, useless unless they interest people. As always, I put everything into extremely basic terms in order to benefit the entire community. Last thing I want is to look like an egghead. ;) Lol

this is amazing stalker

Good job seems I'll be swaping out my .20's for .28's
and I think I'm going to wash a bag and see how that flys.

A little insight - .28 to .30 involves the addition of certain materials (trade secret) to increase the BB weight WITHOUT using compression. Since Stalker has let my cat out of its bag a little (no worries, its worth it to have a good series of tests like this) I can address this a little bit. In .20 to .28 you can use straight bb substrate material (polar bear snot) to gain weight - that however hits a wall at .28 where you are basically faced with a choice - compress your product or use an additive. Compression is bad because after a certain point it it causes the product to become brittle and shatter on impact - which is a safety hazard. It also has a negative effect on spherical balance, causing the material to redistribute unevenly (I'll leave you to draw your own conclusions as to why this is important). Keep in mind there is no direction in which to load a BB - it has to pass through the hopup in whatever position it comes up out of the mag in, hence spherical balance and distribution is critical to consistency - and there is where my primary investment in my product is and is probably the hardest thing to replicate.

Anyways, Stalker is right on the money so far - I've not given him any proprietary information for his testing, which is interesting to watch because he's seeing the results and behaviour of engineering decisions made to make a better more consistent product and his tests bear this out.

Ya, Scarecrow has told me nothing, I've just found similar results in the past with better (and worse) BBs, namely the air bubble inside (never been much of a secret, I learned of it years ago when reading up on airsoft). Like I pointed out, better and heavier BBs tend to have very small bubbles in the center of the BB, where others have a single BB that is often offset to one side (large exaggeration, but picture trying to throw a half filled frozen water balloon at a target far away (say 40ft), then just drop it down to how a BB with a large bubble closer to one side will react when spinning because of hop up).

Might as well point it out on here, I posted a link to this thread on airsoft retreat, and there's a discussion going on. Scarecrow, feel like selling Bastards down south? ;)

http://www.airsoftretreat.com/forums...2976#msg572976

Interesting stuff.

.28's it is.

Stalker it's in the works We have made contacts in upstat NY.

Good, now get heavier BBs made. :D

Thats been in the works since the .30 product. I am seeing if it can be done for this next spring order. If so, it probably will be .33 or .34. I am looking into heavier ones as well.

Depending on the interest I may just do a special order on the heavy stuff - have anyone interested in say .34 buy 10 bags upfront or something in order to make sure the order is workable. I don't want to get stuck with 1000 round bags of .34s that take people 2 years to go through...

If I had the money at the time, I'd willing to buy a large amount of .34 BB's to give them a shot.

(I do enough target/practice shooting indoors anyways, and always seems to be limited not by how much time I have, but how much ammo I have sitting around)

It gets so windy at some our fields SGM's veer off course as much .12's do on a breezy day, and after that it's all luck.

Easy plan, take 3/4 of that total and sell them in the US, there are a LOT of interested players in the Sniper's Perch that are interested in a new type/weight of heavy precision sniping round. And a few wanting 0.43g also, but they are largely those that run 600fps+ rifles (much smaller market).

Oh ya, guaranteed I'd be buying a few bags of 0.34g if you get them out. Be cooler if they could be made a light grey colour (still easy to track from the shooter, yet harder to see when on the receiving end of them).

DUDE, I've been bugging SCARECROW since his induction as "the BB Bastard" to start carrying .36's....and I mean for years, with nada, zilch, 0.0 on the .36's...ggrrrrrr.
But, if he can come up with a mid-heavy weight BB (such as the suggested .34's) I might forgive him for all the years I've had to pay more than $30 a bag for my graphite coated .36's......and BTW; am I the only one running graphite coated .36's anyways???

SHA DO

I'm with Sha Do, As soon as there is heavyer BBs (over .30g) available, I'm buying a reserve!

I keep hearing good things about BBbastard products. I'm the kind of shooter that incurage good ammo!

Well, I carry a small stock of dedicated 0.36g BBs for high wind conditions with my M24 (although I still have to re-adjust my hop up which sucks), but mostly my 0.36g have been getting me kills out of my KSC G19 out to (sometimes past) 100ft. ;) Heavy BBs rock through brush and for distance.

nice info il take good notes !

Thanks for such an informative thread, Stalker. bastards FTW. you do get what you pay for compared to other leading brands in the market.

i'll be interested in your .34g bastards the next time i do another order with you Scarecrow. :D

I aim to please guys, and I'm probably one of the very few that has the time, means and ability to shoot anytime I want at home (30ft basement, but also have access to a 90ft indoor "range" that I use a few times per year to zero at longer distances and adjust hop up).

Looks like I've become a pretty staunch advertiser of BB Bastards on Airsoft Retreat, seems one or more think that if they want Bastard 0.33g or 0.34g BBs they have to buy 10 bags as a preorder. Of course I'm telling them they need to show interest to Scarecrow, which will settle his mind and allow individual sales as always. Maybe it's the way I typed the info, maybe it's the way some of them understood it. Anyways, keep tabs on that thread down there, that will largely be 2/3 of the Bastard market if things work out well.

I'm in the process of setting up Warchild (hopefully) to carry the product in NY State, so those in NY can get the product locally the same way local suppliers here supply the product. I wince everytime I fill a one $10 bag order and then have to charge $6 to $12 for shipping. I prefer that people be able to buy at the field or at a local favorite retailer - BBs are important but really are a small part of the game when it comes down to it - it shouldn't be an onerous job getting a decent supplier for them.

Agreed.

Our snipers are chronoed at 450fps... wtf do you guys plan to hit with a 0.34g BB??? lol

YOU.

Hehe, good one Scarecrow! VERY good one!

Ronan, fields with sniper limits have those limits set at 0.20g BBs, aka. 450fps with a 0.20g. As the BB weight goes up, the velocity goes down. Difference in 0.36g and 0.20g that I've seen repeatedly is roughly 100fps, so a 450fps rifle with a 0.20g BB will chrony at 350fps with a 0.36g. Therefore, all BB weights in between those two will also fall within that velocity range. I'd guess that 0.34g BB would sit around 360-370fps, will be easier to get the rounds farther than 0.36g (not as powerful a gun required), and be more wind resistant and stable than 0.30g. I'd prefer 0.33g, but I honestly can't say why (other than in between 0.30g and 0.36g) or which weight would be better, if much of a differnce at all. I mean, 0.01g is pretty tiny.

just out of curiosity, what does your M24 crony at with .2's stalker?

I'm one of the guys from ASF, I'd be interested in .34 BBs

Welcome to ASC!

As you can see I've invited some of the Airsoft Retret forum guys to register and post on here to support interest. Welcome reddeth!

This is one of the issues I'm trying to figure out, my M24 decides on a nightly basis what it wants to shoot at. One night it'll sit around 508fps, another 490fps, another 480fps, another 520fps. No adjustments, not anything, it just does what it wants. Even the temperature doesn't fluctuate that much (generally right now it's sweater temp downstairs, maybe in the low to mid teens). Only thing I can think of fluctuating is the rubber hop up unit and the rubber piston head (like in a vacuum tube amplifier, the only things that can wear out are capacitors, namely electrolytic, and the tubes themselves, nothing else will wear out or vary under normal temp ranges) but I'm not dealing with extreme temperature fluctuations, so I'm really at a loss right now.

Humidity? Water and silicone oil don't mix well, so any oil residue in your gun (hop-up rubber) will force water to the surface, altering your hop up. Just a stab in the dark there.

Possibly, but I haven't noticed much of a change in that at all on a night to night basis.

Jay.. how will you compete with name brands like AE and KSC who charge the same price or less in the US than you do up here?

Simple, I don't plan to.

Reason is KSC and AE are not the same quality in any way shape or form. I've spent considerably more time and money making a more consistent and better shooting product than them. And based on my sales figures year over year, each year my sales about doubles. So thats gotta hurt AE and KSC at least in Canada. This year we'll be selling more into the northern US. At most the Canadian dollar will remain at par or will dip down when you actually exchange it, so even if they price match, once you add duty, taxes and shipping, Bastards are still a better deal both dollar wise and quality wise.

I've always bet on airsofters who prefer to pay perhaps one or two dollars more on a bag in order to get a better product.

Also, I unlike AE, KSC, et al. I don't have to answer to airsofters with jammed and broken guns due to shit materials, compression manufacturing, and shattered BBs due to widespread distribution of airbubbles in the substrate. I'd rather pay a little more and charge a little more to avoid those phone calls. Unlike those makes, you guys have my name, phone number and address - I am not some anonymous Hong Kong ricebag pusher who suddenly doesn't know who you are when you have a complaint.

one simple cliche will sum up Jay's products: You get what you pay for. 'nuff said.

Now that I had a bit of time away from the wrokbench....... another MK23 spring run of tests.

0.20g:

214.2
216.3
217.4
219.0
220.8
221.4
219.4
212.9
217.3
218.8

Average: 217.8fps
Spread: 8.5fps

0.25g

196.8
199.6
198.9
199.0
199.0
200.0
198.0
198.9
194.2
196.0

Average: 198.0fps
Spread: 5.8fps

0.28g

180.6
181.9
179.4
181.5
184.1
181.4
185.2
182.1
182.7
175.5

Average: 181.4fps
Spread: 9.7fps

0.30g

179.3
178.6
179.2
181.6
178.1
181.1
180.6
178.8
180.0
182.2

Average: 180.0fps
Spread: 3.6fps

Yet again, the 0.30g show very tight tolerances and consistnacy, seems for the most part my tests have an average spread of roughly 4fps.

Welcome indeed....any opinions expressed by experienced "outsides" is a valuable resource, and is always welcome.

SHA DO

you should put that on your site as your mission statement along with a link to this page so everyone can see it.

Well ive said it before and ill say it again nuthin but Bastards in my guns and you DO! get what ya pay for ive tried all kinds of other ones before and now im hooked i swear Scarecrow sprinkles them in a addictive residue before he sends them out. Ive also noticed that Bastards dont shatter nearly as often as say KCS Perfects or Excel.

That's a really good test you got there m102404, if you get any other barrel lengths be sure to post them up, and thanks for the info.

Diffrent hop ups will slow down your BBs diffrent amounts, aswell as how much "hop" your using. Also this doesnt have much to do with a BB study as it does a barrel study?

He just pointed out the same 25-30fps drop with 0.25g BBs as I posted up.

oops missed that last line, lol. The barrel thing really could be in its own thread, thats pretty interesting

I'll toss in one interesting fact regarding different BB weights................. there is a distinctive pitch change the heavier you go. Is something that Testie pointed out in my basement when we were testing (i'd shoot and call out, he'd write down) but he noticed a more of a thud with heavier weights as opposed to the thwack with lighter ones. Is something I noticed years ago when I started loading the first dozen rounds of a mag with red 0.12g BBs (reminds me, I need to buy more), then fill it with either 0.25g or 0.28g. Used that as a low ammo indicator (reduce dry firing of the gun, but also got some surprise kills with them too), not only see the red BBs overhopping, but the sound of the gun firing changed to a higher pitch as well.

Shorter barrels means the BBs spend less time in the confined space of the barrel and thus less time with backpressure behind it accelerating the BB to its ultimate destination, the crown of the barrel. The same principle applies to firearms - you do get velocity drops if you compare the same bullet weights/powder/primer loads to lesser barrel lengths.

The pitch change makes sense because as the weight of the BB increases there is greater backpressure, or blowback. In fact, I would posit that if you test with a longer barrel, you may actually see the opposite effect (even greater acceleration) because the backpressure is higher and the BB spends more time in the zone of acceleration, ie: the barrel.

I don't have stats on that, its more a rule of thumb, but the ballistics of real bullets are very well known and calculatable. In fact I have a program called Quickload, which calculates velocity, chamber pressure, etc and takes inputs like barrel length to do this.

I think this may be stickied somewhere I remember reading, but just wanted to check. This is true up to a limit, right? Beyond a certain length of barrel, the volume of the barrel gets close to the volume of the cylinder stroke. Then the "suction effect" will reduce fps - the backpressure runs out before the bb has exited. The air rushing down the barrel has expanded to its normal atmospheric volume, so will not expand anymore. Now the exiting bb has to "pull" on the air behind it, creating a lower pressure behind it than the pressure in front. The bb is decelerated again before exiting and fps drops. Presumably there is an optimum barrel length for every cylinder/piston, where speed is at its maximum.

Yes Bontic I should have probably qualified that but I thought it was evident. Once you hit the end of your accelerate (ie: positively pressurized air) if it is still in the barrel, friction will begin to decelerate your BB, and the recycling piston will suck air into the barrel, further decelerating the BB. So it is critical that your bore size on your cylinder has enough volume to push the BB to the crown of the barrel.

I don't know how much air a cycling piston is actually capable of drawing down any barrel. Between a vented piston head and the nozzle being retracted at the start of a piston's rearward travel, it should be little to none.

The suck is exactly as Bontic described it, and it doesn't have anything to do with a cycling piston. A single shot bolt action rifle with too long a barrel will suffer barrel suck as well.

Yes, that's why I did not mention the cycling piston as it will not have an impact due to the porting, not to mention that the sector gear whipping around is probably slower than a bb accelerated to upwards of 300 fps in a split second. I will do the math later and see what rof is required before the piston could begin retracting before the bb has reached the end of the barrel.

Hmmm... was not as simple as I'd thought. Need to know som more things about airsoft springs, but as an approximation, probably slightly overestimated:

You need a ROF of approximately 28 rounds per second for a gun firing at 330 fps down a 450 mm barrel for the sector gear to cycle fast enough to begin retracting the piston before the bb has exited. Higher velocities and shorter barrels than this require higher rates of fire before the gear can make it round in time to engage the first teeth.

In general, long barrel, low fps, and high rof means the piston will begin withdrawing before the bb has exited.


If anyone wants to check my work: (if you hate equations and stuff don't read)
Assumptions: 1) that the sector gear releases the piston teeth at an angle of 45 degrees to the vertical and engages again at 45 degrees, passing through 1/4 of a rotation while the piston gets forward and the bb is exiting.
2) the acceleration is near uniform
3) The time taken for the spring to push forward is negligible before the bb begins its acceleration. That is, the bb begins accelerating before the piston head has reached the cylider head. The time for the piston to slam fully forward overlaps with the acceleration of the bb. This may be a source of error in the calculation. The true result could be a lower rof, if there is a significant "compression time" delay. Anyone know how long this could be?

Knowing the spring constant k for a typical airsoft spring (I know some are progressive, but k can be approximated) we can get the force of the spring on the air mass, and minusing a bit for friction and the compressibility of the air, we can get the acceleration, and thus the time taken, and thus can add some of that time on. But I have no idea what range we are talking about.

the math:

using d=1/2 (Vi + vf)t

time taken for bb to accelerate from 0 and exit 0.45 m barrel at 330 fps (100 m/s) is 0.009 seconds.

1/4 of a cycle in 0.009 seconds implies 27.78 cycles/s.

EDIT: true result could be lower still if the sector gear completes the "unengaged" portion of its circuit faster than the engaged portion. Very likely.

Thus, I would lower the estimate still. Perhaps on stock TM AKs and similar barreled guns with low fps the piston does indeed begin cycling back before the bb has exited, especially with a battery upgrade. Porting and nozzle retraction takes care of any potential suck.

Fuck I hate math.

Lol.

Oh, sorry for thread pollutin' by the way. Back to the bbs. You're getting some good info out, it's appreciated.

Kept forgetting to mention, you didn't pollute my thread, you had good info in there, thanks for taking the time to do so.

Kewl - thanks for all the work. More information can never hurt.

The only measurement which would be useful to have is drop at distance and joules energy on impact. FPS is not the only important measure of the virtue or vice of a particular weight. The higher .28 and .30 product has more weight and therefore more kinetic energy so theoretically, its less likely to suffer changes in trajectory based on wind resistance. Also, it has better bush penetration through light foliage.

I have noticed a run on the .25 product, but I think once people start into the green ops this summer, the .28 product will get more airplay.

I think you have judge it gun by gun. I do know that I run tightbores almost exclusively and I see .28 works very well in those. I've also tried the .28 in a stock TM M16A2 and was very surprised to see only about a 10 to 15 foot loss of distance - which to me is worth it for the definite on-target presence that is created by the .28 impact - people feel it even through gear.

And the shooter can hear the hits as well. Makes it easier to hear a guy get plowed, then call him out if he doesn't call hit.

"Sorry, I didn't feel it!"

"You fucking well heard it though, I hear three BBs hit you all the way over here you bastard! Two on your gear and one on your BDU!"

"DOH! Hit!"