The Springfield Model 1869 was one of several model "trapdoor Springfields", which used the trapdoor breechblock

Breechblock

A breechblock is the part of the firearm action that closes the breech of a weapon at the moment of firing....

 design developed by Erskine S. Allin. Originally, the trapdoor Springfields were created to convert Model 1863 Springfield rifled musket

Rifled musket

The term rifled musket or rifle musket refers to a specific type of weapon made in the mid-19th century. Originally the term referred only to muskets that had been produced as a smoothbore weapon and later had their barrels rifled...

s to breech loading rifles at a relatively low cost.

The Model 1869 Cadet Rifle was a shortened version of the Springfield Model 1868

Springfield Model 1868

The Springfield Model 1868 was one of several model "trapdoor Springfields", which used the trapdoor breechblock design developed by Erskine S. Allin. Originally, the trapdoor Springfields were created to convert Model 1863 Springfield rifled muskets to breech loading rifles at a relatively low cost...

. It had a 29.5 inch barrel, compared to the 32.5 inch barrel of the Model 1868, and had an overall length of 48.8 inches. The Model 1869 was produced using Model 1868 receivers and breech blocks, but used a stock that was manufactured specifically for the Model 1869. The Model 1869 had a narrower buttplate and the stock around the barrel was thinner than on the Model 1868.