The "bangs" were not from the Sidaway area of Richmond ( that's way over to the 99 hwy ) as Canso mentioned & nope to buzzbomb to your sujj. that it may be "noisemakers" to spook birds away from the airport. ( definitely not bangs from farmer fields; but your right in the summer there are a lot of bangs from fields to chase away the birds from eating crops. )
Both good guesses but as I live in south west Richmond & the 5-6 quick loud bangs were from the south east direction.
As the land is flat the noise travels quite far.
I'm convinced it has to be hunters shooting birds as they flew overhead.
3-4 hunters could pull the trigger & make these rapid shots.
Gee my memory has been jogged as another day I heard a lot of bangs as well ; more so than the bangs mentioned.
Around Oct 31 I think
On a serious note, one of my past jobs was being a floor waxer.
Did that job for 8-9 yrs & was at a dif building every night. North Van ,downtown,Burnaby, New West. Poco Delta Richmond on & on...but one night as I was getting my equipment from my truck ( floor machine,wax ,mops buckets etc ) a very very loud bang went off which seemed within a block away.
Just one loud bang.
This was just over near #6 just south of Bridgeport.
In that case I called the RCMP & told them about it.
I assumed they sent a car to check it out.
Later I seen a mobile security car & I told the guard about the "bang" & he responded that he heard it too.
Ya just never know, I mean a guy could of been shot in a drug deal gone wrong or "whatever".
In Isreal they get small missiles sent over from Gaza so this one loud bang I just mentioned would be small "potatoes".