I agree that the artifacts may have been moved several feet from the original location due to the soil being turned up year after year. But, the majority of the near-surface artifacts will have been moved in a similar manner, so their grouping will generally stay uniform. By plotting the location of the artifacts, patterns emerge. Since you are talking about a regimental or brigade battle line that extended for several hundred yards, a few feet from the original location is not crucial to interpreting the patterns.

As for the flintlock in the Clemmons Field, most evidence points to this being from one of the Missouri State Guard Divisions (most likely Clark's 3rd) and not from pre-war usage. Prior to Pea Ridge, there were 2 main semi-permanent camps, Camp Stephens, in the Little Sugar Creek valley and Cross Hollows, north of present-day Lowell. There is no record of the Clemmons field being used for any military purposes prior to Pea Ridge. A camp there would have served no military purpose as it would have sat along a secondary route, the Huntsville Road. On the other hand, the Elkhorn Tavern site, a half-mile to the west, was of great military value. It sat at the junction of the vital Telegraph Road and the Huntsville road. It was used continuously by the Federals from February '62 until the Tavern was burned sometime around January '63. Finally, if there was a campsite, there would have been more than just the one part.

At this time of the war (March '62), flintlock muskets, such as the Springfield M1822 & M1840, were still available from the state arsenals. The Federals converted thousands of these into percussion weapons in the first years of the war. For Pea Ridge, the 3rd Louisiana Infantry, which Van Dorn considered the best armed & equipped regiment in his army, was armed with a mixture of percussion & flintlock muskets and M1841 rifles. The ordnance issue prior to the battle included a large number of musket flints. Since the Missouri State Guard was plagued with critical supply shortages throughout this period and had to rely on the Confederate quartermaster and ordnance departments for arms and equipment, it is highly likely that Clark's 3rd MSG Division, as well as the other divisions of the MSG, was armed with a mixture of weapons, including flintlock muskets.