Pete;
I’m in a little different climate than yours, but the key to a good durable driveway is; a slight crown to the bed, drainage (ditching), a good lift of baserock and then a topping, which from what you describe would probably be great.
For a really good, long-lasting road, grading and compacting with a vibratory roller as the rock is spread is really worth the time and expense (and it’s not that expensive to hire a grader and rent a roller).
Another good element, especially here on the west coast where it gets pretty wet in the Winter and Spring is to lay “road fabric” over the bed prior to laying the base and topping. Road fabric is kind of like landscape cloth…a heavy weave fabric that comes in wide rolls. Really keeps the road bed in shape for a long time.
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Nice ta see ya around again, Pete.
Just a strong second to Notchman's advice.
I wouldn't skip the mat under the gravel. I don't know why there work, but I have no doubt that they do. They seem to keep the gravel from sinking down into the dirt and disappearing over time.
Drainage is critical in keeping ANY road surface in good shape. Next time you're driving and see a pothole or bad spot in the road, look around and see if the water drains off quickly or not. The vast majority of potholes are caused by lack of drainage, IMHO.
Gravel will need re-graded once or twice a year to keep a crown, depending on traffic. With the mat and good drainage, they should be able to get by for several years without adding a lot of gravel.
I'm not sure about the "304" product you mention. I've always started out with something like 3" rock, then come back over the top with "roadpack". (Also called "CA-6" around here) It has rock from 3/4" down to fines, and packs well. I would be concernd that if you ONLY had fine stuff, it might no hold up well.
What was in those Scooby snacks, and why did Shaggy want them too? He WAS the only hippie-looking one in the bunch...
One of the problems with a gravel driveway is the dust that occurs once the road is compacted and everything has settled in - a dry period and you will get dust as you use it. A solution to this is to lay down a layer of crushed asphalt - essentially millings from highway rehab jobs. A dump truck can deliver and spread the millings - best to do it on a very hot day and if you can rent one, get a roller to compact it. It won't be a true asphalt driveway, but it will look fine and you won't have the dust of a gravel driveway and it's a lot cheaper than a straight asphalt one.