***Things I forgot:

Gun accidents were responsible for a bunch of KO’s on the Oregon Trail. A lot of first time firearm owners had a similar attitude as my 6th grade self when hitting the General Store and bought way too many guns before they set out. Because of this, by the end in 1869 it was not uncommon to find firearms discarded along the trail. 

Also The Oregon Trail did end in 1869, the Transcontinental railroad was completed. This  linked East to West by rail so nobody was walking that ~3219K anymore.