I'd go for damsons. I don't see any thorns just fruit spurs.

Agree with SBG damsons

Sloes are smaller than most damsons, but it's difficult to judge the size from the picture. Sloes tend to be more of a round shape than Damsons which are slightly elongated. Also, the leaves of sloes are a bit narrower than Damson leaves, so I would say they are Damsons.

Thanks for replies, def no thorns and fruit is elongated not round so pretty sure I've got damsons. Don't think I've ever eaten them before.

make lovely jam :o)