Heavy weight bb different brand, same manufacture?!?

[kullwarrior]

I did some window shopping on heavy weight bb (not bb bastard) and found it really strange that many companies offers heavy weight bb having the same colour pattern

Brand of question includes:
Madbull Airsoft
King Arms
WE Airsoft
EAiming (don't know who they're outside Airsoft Tiger)

Size: All claimed to be 5.95 +/- 0.01mm (I really doubt that, it means standard deviation 95% of all bbs in that bag are between 5.94 and 5.96)

Colour:
I just found it really strange all of the colour seems to be the same in respective weight category

0.43g bb are all black
0.40g bb are all Coyote Tan or Light Brown
0.36g bb are all grey
NOTE: Many retailer list WE as all weight infact only their 0.30g or lighter are (according to respective distributor listing)

Now before you guys jump on BBBastard being one of them, it's not likely.
BBBastard are 5.98mm bb and the colour is off for the weight

[venture]

i never noticed that. it just shows what we all know. there are less bb factories than bb companies.

i am trying goldenball now. they claim +/- .02MM . Which is a more realistic claim. my micrometer finds no difference in a small sample. sometime i will compare samples of 200. the little sample i did showed madbull precision bbs at about 30% outside the 5.94-5.96mm range. Goldenball showed about the same even though they have a more modest claim.