Place ripe raspberries in a half gallon jar, filling to the shoulder.
Cover berries with water, filling also to the jar's shoulder.
Pop a lid into place and either place the jar on a plate and push to the back of the kitchen counter or place in fridge for the infusion process.
If left on the kitchen counter, break the seal daily for 6-10 days. Refrigerated? Just let it sit for 6-10 days.
When the juice is bright red, line a bowl with a cotton cloth.
Pour the jar's contents into the bowl and knot the 4 corners of the cloth together.
Hang where juices can drip into the bowl below and leave for about 1 hour.
Rinse infusing jar and pour raspberry juice back into it.
Cover the mouth with fabric, paper towel or a coffee filter and fasten down with a rubber band to keep fruit flies out.
Leave it to ferment for 21-28 days.
Test for a finish by sealing up some of the vinegar in a small jar with a tight fitting lid. Leave out at room temp for 3-4 days and break the seal. If no puff of air was released, it's ready to be bottled and stored.
Bottle in a jar with a plastic lid or a jug or bottle with a cork or plastic lid.