I think volunteering & sport were the best things I did for meeting new people, that got me a whole load of acquaintences. Remember not everyone you meet will make the 'deeper' jump from acquaintence into friendship, no reflection on you, just not everyone is meant to be closer friends - that is why friendship connections are special when they happen.

For a long time I personally had a lot of acquantences and no close friends - I used to fret over it, I tried hard to make friendships but looking back they weren't meant to be. If it's meant to happen it will happen, try to relax because putting pressure on yourself can make you feel tense around people which will make things harder.