This little spring branch is lovely and well manicured -- a great place for a family picnic. The area has grills, picnic tables, toilets, etc., and it is routinely mowed to make access as easy as possible. There is good quality water, and the branch is stocked frequently by the Missouri Department of Conservation (every few weeks from March through October), so you will catch fish. There are only a few downsides.
First, the spring branch runs less than a 1/3 mile long before dumping into the Big Piney, so it takes no time at all to cast to every fish present. This also makes it nearly impossible to find that lunker that's been hiding out in a remote spot, because there are no remote spots. Second, the spring branch is on Fort Leonard Wood, meaning you MIGHT have to jump through a hoop or two to gain access. Even when they're being strict, this is really no big deal, though. If you usually keep a firearm in your truck, you might want to leave it at home to avoid some delays -- I'm sure you understand the issue. Third, the stocking dates are announced in advance, which can lead to a trout park atmosphere on stocking day, and a nearly empty creek a few days later.
For most of the year, Stone Mill is operated as a put-and-take fishery, but there is also a winter fish-for-fun season that runs from November 1 through February 28. During this time, you may fish 7 days a week from 8am to 4pm only, using flies and lures only, with soft plastics specifically forbidden. Click HERE to visit the Fort Leonard Wood page explaining the post fishing rules in more detail.
The easiest way to get there is to enter the fort through the East gate. On I-44 just East of the Fort Leonard Wood exit, take Highway J South. As soon as you cross Spring Creek, turn right to find the East gate. As soon as you cross the Big Piney River, turn left. Drive a couple of miles and veer left when the road splits. Again cross the Big Piney and immediately turn left, following that road to the parking area.
IMPORTANT NOTE: access requirements change periodically depending on the political environment in which we live. After all, it is a military installation. So, there will be times when the rules are relaxed, and you'll just have to show a driver's license. But, if tensions are high, the East gate guards might turn you away, directing you to the front gate (just off I-44) to get checked in. If that happens, park at the visitor center, and go in to obtain a guest pass. You'll need your driver's license, vehicle registration and proof of insurance. Then you'll have to drive up to the inspection station another 30 yards up the road, where an officer might search your vehicle. The entire process will only take 10-15 minutes, and it's really no big deal. Just be sure to remove the liquor, drugs, assault weapons, and pipe bombs from your trunk before you go fishing. ;-)