Cans collapse why?

[Jssdk]

Need some help to understand this. Never seen it before.

I prime with sugar and then condition for 2 weeks in cans made of aluminium.

I have recently noticed some of the beers not all collaps when chilled. They were perfectly firm and carbonated before this. Now the collapsed cans are flat and stays collapsed. But why?

 

[RM-MN]

Your priming sugar is not getting mixed well enough. The cans that get the sugar in the beer carbonate and get really firm. You probably didn't notice the cans that weren't firm until you had put some in the refrigerator and had them collapse from the negative pressure when the air inside them was cooled.

 

[hotbeer]

Unless you offer some other little tid-bit of information, then I'd have to agree with @RM-MN .

Though it might also be that they all are evenly carbonated, but you didn't get the vols that you expected. So chilling the beer puts more of the CO2 in the head space back into the beer.

Did you leave a lot of head space in the cans? If so maybe it is just showing a practical result of Boyles Law.

How long have you been canning beer?

 

[Golddiggie]

This is why I can my beer fully carbonated.

 

[DuncB]

Have you used this when you work out your priming?

https://www.brewersfriend.com/beer-priming-calculator/
Also dissolve any priming sugar in a little boiled water and then put doses of liquid in each bottle, that way it's all dissolved and accurate. The other thing to watch for is missing a priming dose or double dosing. So I dose a bottle then put it on the floor, if they are all stood up together you can miss one or double dose, take no chances.

But as per @Golddiggie I counter pressure fill my bottles and now only prime the rare brews that need bottle conditioning and keeping a long time.