The first attempt in processing of Wild Grapes was quite successful, but very labor intensive. The worst part was destemming the grapes. Long and tedious process, not to mention messy.
The second time around I decided to try to take some shortcuts and see how it will turn out.
The grapes I collected this time was more ripe and therefore quite a bit less tart.

First I soaked them in cold water and attempted to eliminate as many green and bad grapes as I could. Good swirl in the water also eliminates critters (spiders, small slugs etc.).

The washed fruit, stems and grapes together, I added in batches to the stock pot simultaneously crushing them with potato masher.  I did not try to hard. The goal was just to get juices going and start the cooking process.

After the crushed mass boiled I cooked it for approximately 10 minutes, or until majority of grapes disintegrated.
The whole thing was poured through regular strainer and pressed with big spoon to extract as much juice as possible.

Result was approximately 1.5 liters of juice.

After that I poured juice through chinois strainer back into stock pot and put it back on stove.

After liquid boiled it was cooked on  medium heath for approximately 20 minutes.

At that point I mixed in gelatine and cooked 1 more minute.

I poured the liquid  into the clean mason jars and processed them in boiling water for 15 minutes.

The end result.

 

The taste was not different than juice obtained in previous attempt, with destemming of the grapes