Rifleman Q&A: Mysterious ‘Trapdoor’

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posted on April 25, 2023
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1870 Springfield Officer’s Model Carbine

Q: I have what I believe to be an 1870 Springfield Officer’s Model Carbine. What I have researched is that these rifles were converted from caplock to a centerfire mechanism, and vernier sights were added. The rifle I have is converted from flintlock using a similar, if not the same, mechanism for firing centerfire cartridges. The only marking is found at the top, rear of the breech and it reads:
“Model 1870.”

I cannot find a single callout in Flayderman’s reference book or the NRA museum website. Is my conversion authentic?


A: You have an interesting piece. “Trapdoor”-style rifles and carbines have regularly been altered to look like flintlock muskets and rifles, blunderbusses and even pistols by the motion picture industry for use as prop guns. These conversions are generally fairly crude (only good enough to look good on camera) and are normally undertaken using later arms chambered in .45-70 Gov’t. in order to take advantage of readily available blanks. 

Your piece, on the other hand, it being a Model 1870, is most probably chambered in .50-70 Gov’t., unless it has been re-chambered. The work appears to be of excellent quality; I have never seen anything quite like it and can only opine that the work was likely undertaken by some gunsmith or talented hobbyist who wanted to fire a “flintlock” without all the attendant bother. The fact that the piece also has an anachronistic, vernier-style rear tang sight indicates that it was intended for shooting rather than just for show.

—Garry James, Field Editor

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