Yes interesting indeed.
I understand the difficulty in maintaining such tight tolerances in the manfacture of lead pellets.
But what I do object to is stating a particular dimension when it appears that is not how it is.
However I do have to question the methods used to measure / prove a particular size.
Measuring accurately using calipers I would think is nigh on impossible when it comes to lead with such acute angles.
I read that they are set to size and the pellet dropped or placed within the jaws, obviously an attempt to prevent any force on closure distorting the soft lead.
If anyone has used some sort of laser measuring device I've not read about it, yet. Or shadow measuring I think I read about somewhere, accuracy in that case would also be questionable. Possibly a very accurate reamed / tapered hole to gently drop the pellets through I guess could work and possibly the least complicated method to prove a head size.
I have some Olympic grade target pellets that I shoot through my Baikal IZH 4MM target pistol. The pistol is so capable that I questioned whether I missed the target with the next 4 pellets I shot bench rested at 10M! Literally one hole barely larger than the first pellet hole, that was with iron sights.
OK it's only 10M but in order to do that those pellets must have been identical, or as near as possible.
I would be interested to see what the outcome of measuring / comparing, pellet for pellet, target pellets of this quality would be?
If these show tighter accuracy then we will know that it IS possible. Now whether it is practical / doable churning out thousands of pellets, which go through stringent selection also, without putting the price through the roof, is another matter.
On a happy note, I've so far found my Steyr to be liking JSB 4.53'ish (I think we have got to put "ish" after the stated size from now on!) 2 dies and 2 differing batches and years for that matter are proving practically as accurate as each other.
I'm shooting outdoors, an indoor range using a "hooter shooter" may show some slight differences in preference.
Whether to create waves over this size / consistency issue is a clever idea I'm not sure. A price hike and a reduction in availability may be the result as JSB would have slow production rates, so be happy or challenge?
If everybody from now on refers to head size as; 4.50'ish, 4.51'ish, 4.52'ish .... keep sticking "ish" after every mention of head size JSB may get the hint, they can't sue everybody!