I killed a calm antelope buck 4 miles from the road in hot weather. Within minutes of handling the carcass there were easily 100 flies buzzing around. I realized that although all the meat would easily fit in the one Caribou carnivore3 elk-sized game bag I brought, all the meat balled up together would not cool fast enough. I should have brought 4 of my bags with me to spread the meat out.
I opted to surrender to the flies by quartering the carcass, and set the quarters and backstraps in the little shade provided by sagebrush, to allow some evaporation and cooling to begin.
When I was ready to leave I put all the meat in the one bag and hoofed it 1.5 miles to a pinion in a breezy place on the shaded and slightly cooler side of a bluff (NE since it was early afternoon).
I took the meat out of the bag and draped it on the branches to continue cooling, for about 4 hours. Flies again showed up immediately. At this point the meat was sufficiently cool, so it got loaded into my pack again and an hour pack out to the road. I put the bag in the middle of my cooler surrounded by ice.
I knew there were fly eggs on the meat, they hatch in 24 hours, but not unless the meat is at least 60 degrees. I had basically made them dormant.
If eggs do hatch, the maggots will move slowly, but still start munching away in the meat at any temp above freezing, and the meat is ruined.
40 hours later (today) I began butchering. All the fly eggs were within 2 inches of the ball joints on the rear hams. Flies instinctually lay their eggs in the place that will stay the warmest for the longest as meat cools, which in my case was the ball joints. I trimmed an extra inch around the eggs and discarded that meat (basically 2 disc-shaped pieces of meat 1” thick and 4” wide).
Just to be safe, I meticulously inspected all the other meat and not one fly egg was found elsewhere. The meat tastes great, as I ate the tenderloins for supper. The only remaining consideration here is that the surface of the meat has bacteria from all those flies walking on it for 4-5 hours. Kind of gross, but nothing that a thoroughly cooked steak won’t remedy.
Re: which brand to buy - make sure not to get disposable bags such as coolabuck, unless you really do plan to discard them after 1 use. Caribou bags cost x2 as much for a set, but you can reuse them many times - I have and they work great.