When I first took an interest in precision shooting all I had were factory hunting rifles. At that time I believed most everything I heard or read about the topic of hand-loading for accuracy. I spent a lot of time and money attempting to make my hunting rifles shoot better by applying precision loading techniques. None of it seemed to make much difference until I bought a good varmint rifle. Later on when I bought a good benchrest rifle things finally started to come together for me.
The typical factory rifle has so many factors working against it in terms of intrinsic accuracy that the most meticulously crafted hand-loads can only go so far to help it shoot better. In my experience, seating bullets out to touch the lands is one of those accuracy enhancement tricks that has provided little to no measurable improvement in my factory rifles. Most of my factory rifles have had so much freebore in them that bullets could not be seated out long enough to make contact with the lands no matter what. When my hunting ammunition is loaded to function through a magazine the bullets may be jumping a quarter inch or so before they contact the rifling. But they are meant for hunting and to me pure accuracy is a minor concern in a hunting rifle. Take a coyote hunting rifle for instance. The way I hunt coyotes, most shots will be under 200 yards and many will be under 100 yards. The rifle simply does not need to be real accurate. On the other hand, it must be 100% reliable and the ammunition must be durable. A typical day of coyote hunting involves driving from stand to stand, loading and unloading the rifle every time I get out of and back into the truck. The cartridge gets a good workout riding up the feed ramp and then yanked back out of the chamber several times a day. I want my bullets firmly held by the case neck. That means they will be seated at least one caliber into the case. I don’t care if they are jumping an inch to the rifling
I’m not attempting to discourage anyone from trying to improve the accuracy of their factory rifle. But I feel that improvements to the bedding and trigger will go a lot further than things like bullet seating depth. I have found that the biggest improvement in accuracy from a factory rifle comes after you have a competent gunsmith install a good custom barrel on it. At that point the accuracy enhancing tricks that you can do with your ammunition will start to pay off. If pure accuracy is what you are after, mastering the art of shooting off a bench rest and learning to read wind flags will take you even further.