Pellet consistency

[Dave F]

Had a tin of  JSB Exact jumbo heavey 18.13 gr. which seem to have an awful lot of deformed pellets.

Well it's snowing like h.."... Outside today and it's about 0 f so I decided to see how of the remaining pellets were deformed. Here is the result.
Also weighed the remading one!
37 deformed. = 35%
18.0 gr.      6. =  6%
18.1 gr.     14. = 13%
18.2 gr.      29 = 27%
18.3 gr.       18 = 17%
18.4 gr.       2.  =  2%

THis little effort brought the question to mind. How much of an affect on accuracy does a pellet weight variation of  say 0.2 gr. have ?

Had some other tins of JSB pellets so I checked them for deformed skirts and did not find any. Did notice how thin their skirts are compared to H & N , but even though they are thin it still takes quit a bit to bent them like the ones  I have. Just wondering! This entire tin was like this from new, purchased from PA so I know it was not there packaging.

[Ribbonstone]

The 2/10ths a grain is still just a little more than 1%.  I doubt the results, assuming the DIAMETERS were consistent, that you'd shoot 1000's of pellets in order to be able to detect any real difference.  If the diameters vary that much, then you' probably only have to shoot a few 100 shots to see the difference.

Point being that an airgun only knows resistant to movement at the instant of the shot.  Resistance to movement can be by way of weight or by diameter (friction).  So while barrel can shrug off a 1% difference in weight (18.1 vs 18.3) it may really show a difference between 5.50mm and 5.56mm (also a 1% difference).

So if I were to go back to sorting, would do a fast sort by weight (just to get the odd-balls out of the mix) and a detailed sort by diameter.

[Dave F]

I tried measuring the skirt diameter a couple of times with a dial caliper and found it quit difficult to do.
Is ther some technique that makes this easy.
I had a 22 cal Marauder and tried different head size H N pellets and they definitely performed differently.
 From one size to another, with 5.53 being the most accurate.

[Ribbonstone]

Other than a quick visual, don’t normally bother to sort good shooting pellets anymore. Will bother to sort almost good shooting pellets, just to get the “goofy” ones out of the mix (more a matter of excluding the misfits).

When I did, would spend the most time sorting by head size.  Even in good pellets, the skirt are so often out of round it’s hard to get a really meaningful/repeatable measure.

I’d just set up a micrometer as a “snap gauge”.  Pellet heads that didn’t fit though got put in a “fat” group, the ones that did fit though moved on to the next round (tighter gap for each round).  By the time you got down to a small number of pellets (maybe after 4 “snap gauge” tests), I just made what was left my “pee-wee” group.

[Bwalton]

Air Gun Brazil did a extensive test in that respect.