Rifleman Q&A: Mysterious ‘Trapdoor’

by
posted on April 25, 2023
** When you buy products through the links on our site, we may earn a commission that supports NRA's mission to protect, preserve and defend the Second Amendment. **
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

Latest

Suppressors
Suppressors

A Victory That Ends A Gun Registry

On August 5, U.S. District Judge James Wesley Hendrix of the Northern District of Texas held that key regulatory provisions of the NFA are unconstitutional as applied to certain categories of firearms.

Criminal Clues: Tips to Avoid Appearing Like a Soft Target

You don’t have to be the hardest target, but you don’t want to be the softest. Here are some tips on how to avoid becoming a target for a criminal looking for his or her next opportunity.

Beretta A400 Solo: For the One-Gun Hunter

The new Beretta A400 Solo is designed as a no-nonsense hunting shotgun that is an entry point to the company’s premium semi-auto shotgun family.

The Armed Citizen® Aug. 10, 2026

Read today's "The Armed Citizen" entry for real stories of law-abiding citizens, past and present, who used their firearms to save lives.

Review: FK Brno PSD-C

Manufacturers have achieved excellent results with small-caliber bottleneck designs, as evidenced by cartridges such as the .357 SIG and 5.7x28 mm. The .30-caliber 7.5 FK continues this legacy and is now chambered in the FK Brno PSD-C.

Firearm Industry Celebrates America's 250th With More Commemorative Options

For the entirety of 2026, we're celebrating America's 250th anniversary, and the firearm industry continues to roll out commemorative products to mark the occasion.

Interests



Get the best of American Rifleman delivered to your inbox.