Hi Daryel
Prior to the adoption of the 1803 US rifle the government had purchased a number of rifles fron civilian Mfgs. and these were known as the conteract rifles in question. They were not top quality weapons for the most part, just good durable rifles for the use of the ranger units, marines etc.
Several I have seen did not even have bridled frizens or tumblers, since that was not specified in the contract. They were brass mounted, simple furnature, one inch barrels, about .48 cal, barrrels were oct for about 14" then turned round for the rest of the 36" length. Not round and tapered, just round. These were the guns Lewis&Clark had restocked, modified with the new rifle locks, rebored to .52, fitted with slings for the voyage. Least that's the way I read it.
Just informin'