Pressure canning in small jars

I'm wanting to pressure can chicken rillettes which I've done previously in larger jars. I am wanting to do smaller serves though and can get 100ml (3oz) Mason Ball Jars.

Researching is giving different answers as to whether it is safe to pressure can chicken in such small jars, some sites say you can and others say its too small to get proper sterilisation.

Does anyone have any experience with small jars or know if it is safe?

Thanks!

Welcome to permies, Kathy!

I have friends that can chicken in 250ml wide mouth jars which are locally called "fish jars" as they're used for canning salmon. I don't know of anyone canning chicken or fish smaller than that. Hopefully, someone will know!

Proper sterilization?  That doesn't make sense.  Long enough pressure time and it has to get hot enough.  More likely is improper head space in short jars.

I'd say to use a lot of head space, that's the part small jars do badly.
To measure how much headspace you need to can safely: Take one of your old jars that you have used safely, fill it totally to the top with water, take out and keep enough water to leave a proper headspace in that jar. Pour the kept water into your small jar, that's the volume of headspace that you need to can it safely. Will it leave any space for food? I'm guessing no. Put that water into an 8 oz jar, that might leave enough for food.