Swiss No.4 Question

[Gellot Wilde]

I recently bought some more No.4 which I've been using since time began it seems.

However...have they changed the granulation size?

I dropped (drop tube of course) my usual 74grains into the usual cases and found that it was stacking up so much that to get my usual seating depth I needed to loose a full four grains.

The only thing I can think is that they've changed the granulation size.

Anyone else noticed this before?

[Gellot Wilde]

Ok thank you that makes perfect sense.

I am throwing it by weight rather than vol.

Never had it happen before, this is the first time I've noticed such a big change with the Swiss powder.

You live and learn.

[John Boy]

Gellot, every different lot of powder, whether it be black or smokeless will have a different density. So, to maintain the same charge of powder you have to determine the density of the currently used and compare to the new lot.
Easy to do ...
* Volumetric powder measure
* Pour in the powder up to the 100 gr line and then settle the powder
* Pour the 100gr on a scale & weigh it
* If the scale weight of the 100grs is say, 101.3 then the density is 1.13
* If the old lot being used scale weight calculation is 0.955, then the new lot weighs 0.175 grs more. So adjust the difference to the old lot charge if that is your desire.
Me? I'd use the new lot for my charges

[Gellot Wilde]

Ok I got all that fellas.

However lets say after all the batches of the stuff I've had since lets say 2004...it's never varied once until now...like I say first time I've ever experienced it.

I've always thrown it by weight and it's never varied this much.

Rob

[martinibelgian]

Yes, the most recent lot is quite a bit lighter, which gives more volume for weight. As I load by volume, this means I can get a few more shots out of a can... Maybe you should also load by volume? Swiss no.5 (Fg) also changed: it got distinctly heavier for a same volume - the 1st time that it weighs more than no.4. All the other lots of no.5 I had were all lighter than no.4 for a given volume. Ah well, live and learn. There still is one constant in shooting BP: The more powder you stick in that case, the better the rifle will shoot... Well, that seems the case with my rifles!

[Gellot Wilde]

Ok, so there is a change in it...I was convinced there had to be something going on that was different.

Load by volume...well I could, I've done it before. But I'm reluctant to change my 'by weight' system, afterall you know it works Gert, you've seen me shoot. However, on that note...I've seen you shoot and your 'by volume' works fine too. :smile:

[martinibelgian]

Still, That last lot of Swiss no.4 had me scratching my head for quite a while - but I think I got it figured out now - now that I've started my last kg... But yes, there most certainly is a major change. The volume thing didn't work with this last change, I had to put in more volume - and more weight too, I might add.