I've got some of those boxed Premium JSB Exacts - they haven't been out that long but the batch number is already upto 7
Perhaps when they get past 9 they just label all the batches as '0'
That's very interesting, I've got a really really good batch of JSB's from 2013 when I bought a boat load of them, but I'm down to my last few tins now.
I've got one of those Pelletgage head size measuring tools and a half decent set of pellet scales and what I've found with my good batch of pellets is that the head sizes are all very consistent ( the tin says 4.51 but on average 97% of the 200 tested had a head size of 4.50.
They're also very consistent on weight too - I gave up weighing them after i found that everything was coming out between 8.38 and 8.46 grains. I had one or two coming out at 8.50/8.52 this is out of about 50 pellets that I could be bothered to weigh.
My conclusion from all that was that these pellets are great to shoot straight from the tin. They already group very well and give a much better than average BC.
BC at 50m was 0.0265 on average and the downrange velocity was actually more consistent than the muzzle velocity (curiously?)
Anyhoo..... these mega pellets have a batch number of '1' and I'm wondering now whether a batch number of 1 is the best bet to go for. We don't know what '0' means, but 1 probably means 1 - which looks like it's a nice fresh new die being used.
Interestingly, the head sizes and weights of my mega batch are actually more consistent than the head size/weight of the box of 2015 Premiums (batch 7).