I always put the camera on F16 ISO 100 Bulb mode on a tripod (but I shoot from the top of a set of steps to ensure if anyone stands in front of me they are not in the shot), and no-one tends to get too close so never had an issue with the tripod being bumped into. I use the IR remote set on press to start and press to finish. I focus on something at approximately the same distance as the fireworks before they get going then switch to manual focus. I always put the camera in portrait orientation which allows room at the top of the frame for those surprise higher displays and crop accordingly in post.
I watch the fireworks and set an exposure to start as the rockets are launching and leave the shutter open for the duration of the explosion.
I used my DA* 16-50 on a K-3 for these.

WARNING!!!!!
Please be aware with SSD drives that you must switch off indexing and never defrag the drive

It will, and it'll get better and better.

You need to look harder, I have seen more and more Pentax users just recently. A couple of years ago you'd be lucky to see one a year. But lately they are popping up out of the woodwork. Back in July I was on Skomer Island and saw 3 other users, and on holiday in Lanzarote back in September I was shocked to see at least 5, and I wasn't even trying. I appreciate that the numbers here are small in comparison to Canikon but the rise is upwards. I recently saw an article that placed Pentax 3rd in global sales of DSLRs. So let's be positive about our chosen brand we are on the up

My path has been 7 - 5iis - 3 and frankly I rarely pick up the 5 nowadays. The AF on the 3, as alluded to earlier, is awesome in the dark, it's buffer and processing of the much larger files is a step change. The ability to crop closer with the extra pixels is a bonus for little birdies. I have used the Flu card and it is great if you want closer shots of twitchy birds and the Astrotracer works superbly. I know it works on earlier models but the usage on the 3 is much simpler.
Full frame will happen and it will happen in the spring of next year and as far as I'm concerned it is the only thing that would sway me away from my 3, although I'd hang on to it and p/x the 5iis and use it for the wildlife.

I have taken the same route 7 -5iis - 3
I find I'm not picking the 5iis up anywhere near as often any more.
As for the 3 it's processing speed of images is awesome and when shooting at the kart track I found I'd quite often miss shots with the 5 because the buffer was full, but the 3 eats the raws so quick I very rarely have to wait.
Apparently the 3 isn't as good in low light but it really is marginal. My go to camera now.

Cheers Gareth. In the second shot you can make out Andromeda up and slightly right from the top of the volcano

You certainly got a better haul than I did Gareth. The opener is very nice, I also like the shot with the razor fish shell in the foreground

5, 6 & 8 are stunning

I really like this, it's natural and she is a very beautiful lady.