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Practically Shooting

The Trapdoor Springfield


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I wrote this for a now defunct forum, which had a section for article postings. Rather than let it sit saved in my computer, I thought I'd post it here.


Trapdoors are one of those rifles that don't get the respect they deserve. There are Trapdoor collectors out there, but few compared to collectors of other US martial arms.

Most of us never even glance at one lying on a gun show table.

Yet, the Trapdoor had a pretty good service record in some trying times. After some initial trouble with the early brittle copper cartridge cases, it usually worked and did so in some crummy conditions. Of great importance was that due to being cheap and easy to transition to, it allowed the US Army to convert to breechloaders after the Civil War when the country was flat broke. It served in several battles and wars, including two that had a tremendous impact on our country- the Indian Wars and the Spanish-American War.

There was a war or conflict going on during almost all of it's career.

It is the gun that won the west.

But it's history is another story.

I'm going to ramble on about the gun itself.

People usually call it a "weak action". Well, it isn't as strong as a Ruger #1, but that does not make it faulty. Some seem to think that way. I think we have to compare it to guns from it's period. I wouldn't shoot anything in a 45-70 Sharps or Remington Rolling Block that I wouldn't fire in a Trapdoor.

The Trapdoor was made to handle a specific loading, and it DID handle it.

I have found nothing saying a Trapdoor failed in service due to not being up to the task. The fact is, it's cartridge was made more powerful during it's service. Originally loaded with a 405 grain bullet over 70 grains of black powder, the bullet was increased to 500 grains over the same charge in 1881.

Duplicate of M1881 on left, duplication of original load on right.

The fact it cannot contain a load that is pushing .458 Winchester Magnum levels that was dreamed up 90 years later is of little bearing. A hundred years from now the much-loved Remington 700 may not be able to handle a typical load from the time, but that doesn't mean it is a bad action then or now.

The Trapdoor has some mechanical details and features I find interesting, and I don't know how many people are familiar with them.

By outward appearances, it looks simple as dirt. You might not think there would be anything of interest about it's mechanism, but there are a couple of things that stand out once you know about them.

By the way, it was not called the "Trapdoor" back then, at least by the military. It was the Springfield Rifle (or Carbine), Caliber .45.

Breech Locking

I thought I knew how the breech was locked until I got one and then got a copy of the old Army manual. Then I found out there was more to it than I previously knew.

You open it by unlatching and swinging the breechblock up, and you close it by swinging it down where it latches in place. When the breechblock is latched closed, there is a latch (called the "cam latch") that holds it closed by keeping the breechblock from being pushed up and open by the firing pressure. That much was obvious from looking at one, and I thought that was all there was to it.

Well, there is and there isn't. It is designed so that when fired, the pressure holds it down and latched tighter.

Take a look at this diagram from the manual. Our two main points of interest are marked "E" (Hinge) and "F" (Cam Latch):

Item "E", the hinge pin, runs through the hinge pin opening in the breechblock. The hole in the receiver is round. BUT, the hole in the breechblock is slightly out of round. It is elongated fore and aft.

Hold that thought.

Item "F", the cam latch, is what latches the breechbloclock closed. Notice that the center of it's pivot point is lower than the contact surface of the latch.

When the rifle is fired, the elongated hinge pin hole allows the breechblock to push backward just a little. It hardly moves, but it does move. As it comes back, the cam latch rotates slightly since it's contact point is below the centerline of it's pivot point. This rotation cams the breechblock down, holding it closed tighter.

Small detail, but one that is simple, clever, and an important one.

Rear Sight

In 1884, the "buckhorn" rear sight was replaced by a new design called the Buffington sight (named after the Colonel in charge of Springfield Armory at the time). Compared to the previous sight, it is both simpler and more complicated. It offered an easier windage adjustment and a battle sight that blocked less of the target, but its also had five different notches or apertures that can be aimed through and was adjustable from 200 to 2,000 yards.

But there was something else.

Take a look at one, and see if you notice anything peculiar about it:

Can you see that the sliding "ladder" runs in a track that angles to the left as it goes up? Closer look:

This is a built in compensation for bullet drift.

When a bullet is fired from a rifled barrel, it has a tendency to drift in the direction of it's rotation. A bullet from a RH twist barrel will tend to drift to the right. I think the theory is that the larger and heavier the bullet and perhaps the lower the velocity, the more it will show this effect, but I'm not sure.

The new sight compensated for this by sending the aperture and notch to the left as it is raised.

According to the manual, SA had the best marksmen test rifles at various ranges using some rifles having RH twist barrels and some with LH twist barrels. At each range, the groups got farther apart laterally due to the rifling twist causing drift. SA then halved that distance between the groups to determine the amount of drift caused by the rifling, and used that info to know how much to make the sight compensate.

How much drift could there be?

The manual lists the results in 100 yard increments to 1,000 yards. At 100 yards, the bullet has already drifted 1.29 inches. At 300, it's 5.1 inches. At 500, it's 11.5 inches. It's almost 4 feet at 1,000 (which takes 3.29 seconds to arrive at).

With the rifle, that is inside the mean accuracy standards, so I suppose it was worth addressing. With the Carbine, I'm not so sure since at all ranges, the Carbine's accuracy acceptance standards exceed the amount of drift. I don't know if the possibility of 5" of drift is worth worrying about when the Carbine is shooting a group of almost 12".

I don't know how far they ever shot them in actual combat either.

But I still find it all rather interesting.

Other Details

There are other small details to it if you look for them.

The thumbpiece used to unlatch the breechblock has an arm that blocks the hammer from the firing pin if the latch isn't completely closed. The hammer can be cocked and the trigger pulled if the breeckblock is open, but it will fall on this arm.

It has an actual ejector, not just an extractor. Regardless of how fast or slow the breechblock is opened, the ejector will "fire" the empty case out of the chamber. A part called the ejector stud in the bottom of the receiver acts as a deflector to send the case flying over the shooter's right shoulder...if right handed. It should just about catch a left hander square in the face.

I've read this cartridge ejection was quite impressive to Army officers who examined early samples. Apparently, they thought it was just the neatest thing. I'm not sure why, since there were ejectors on arms before, but I guess that doesn't mean it didn't happen.

And it's a simple ejector system. The ejector is basically an extractor with a spring bearing against it. The key is how that spring is located. The ejector pivots around the breechblock hinge pin. Most of the time, the spring is applying pressure just above the centerline of the pin and keeps the ejector retracted. As the breechblock is rotated open, a tab contacts the ejector and rotates it slightly. That is just enough movement to "free" the spring to bear against the ejector on the other side of it's centerline and kick it out.

They made use of cams and overcenter principles in this rifle.

There were near-constant improvements being tested or applied to the Trapdoor throughout it's service. You have to remember there was almost always a shooting war going on. Even though money was almost nonexistant, they had people counting on these rifles so they never stopped developing them.

The breechblock got some strengthening changes, the receiver got widened just a little, the firing pin material changed, the sights changed, the trigger was re-shaped...Literally everything from the buttplate to bayonet got changed at some point. Even the ramrod went through a few changes (yes, they call it a ramrod even though it's really a cleaning rod).

So as you can see, it may look simple as a hammer, but there is a lot more to it than first appears.

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It's one of those seemingly simple things that once you start looking at it, you see all kinds of details. As I said in the post, most of us have walked past them at shows for years and never gave them more than a glance. That's exactly what I did. Those old Trapdoors deserve a lot more credit and respect than they get.

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Soooo... When are you going to escape that state? Say, did I ever tell you about my lifetime carry permit?


Bite me! :-)

We are all criminals here, unless of course, you "Become a mayor, alderman, president, trustee, marshal, deputy marshal or policeman. Pass a training course given by the Illinois Law Enforcement Training Standards Board. This will make you a "conservator of the peace" as defined in the Illinois Municipal Code, Article 3.1, Division 15, Paragraph 25."

I guess this means that they are special and above everyone else. I frown on talking about politics on this site, so we'll just leave it at that.

Funny thing is that I legally carry when not in IL, but can't and don't carry here.

To answer your question - when my kids are out of high school, you might hear the sound of squealing tires. Someday I'll tell you how much I hate this state.



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I lived there for seven years.

I still can't explain to people here what it was like, and likewise, I never could get people there to see what it was like here. In both cases, it's a case of what a friend said about growing up in Poland: "If you have never known any different, you don't know and can't really understand".

I'll tell you what- I cherish how it is here a lot more than I did before. I don't think I took it for granted before, but it was enlightening nonetheless.

Sorry about getting into politics. I'll stop.

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I lived there for seven years.

I still can't explain to people here what it was like, and likewise, I never could get people there to see what it was like here. In both cases, it's a case of what a friend said about growing up in Poland: "If you have never known any different, you don't know and can't really understand".

I'll tell you what- I cherish how it is here a lot more than I did before. I don't think I took it for granted before, but it was enlightening nonetheless.

Sorry about getting into politics. I'll stop.

Couldn't have said it better myself.


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  • 1 year later...

People sometimes refer to the "Sandy Hook Tests" of 1879, where the army tested the Springfield .45-70 Trapdoor at two miles. This test was held on a NJ beach to get the range, and for the sand impact area that would indicate hits. I think this test helped get the 500-grain M1881 bullet and cartridge.

I've read the following article before, and it's been referenced in several places. However, most don't have the diagrams that accompanied the original article. The diagrams showing target impact angles really bring it into perspective.


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  • 11 months later...

Thanks for a great article on the trap door Springfield. I have one that I inherited from my Dad - an Army vet and antique collector, it used to hang with pride over his fireplace. Given today's times, it rests quietly in the safe next to (gasp) an "assault rifle"...but someday, I will take it to the range, just to know...



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Thanks for the kind words. If shooting it at any distance closer than about 100 yards, hang two targets: One to aim at, and one to hit. They tend to shoot at least a foot high. When I shoot mine, I do just as I said and hang two targets one above the other. I hold at 6:00 on the bottom one and get hits close to the center of the top one. This is with the rear sight at the lowest point.

Accurate, but not zeroed for that distance at all. It was meant to knock a horse out from under its rider at a distance reasonable to hit that horse.

Next to an assault rifle? The Trapdoor was the assault rifle of its day. Big heavy stock held on with steel bands for security, big hammer for sure ignition, square front sight base to act as a bayonet lug, trigger guard big enough for gloves. Compare it to the sleek sporting rifles of the time, and the Trapdoor was crude and rugged- an implement of combat. It's the same 100 years earlier. They may look like quaint wall hangers, but compared to the Jäger and PA rifles, the muskets of the 1770s were clearly different and meant for a different purpose. Anyone alive then knew the difference between a hunting rifle and a musket.

So when you hear someone say the Second Amendment was meant for muskets- Smile and remember that yes, it was.

(I've been waiting for two months to say that, but needed the right cue. Thanks for setting me up!)

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  • 1 year later...

Had the Springfield checked out by the local gunsmith. The guys there were appreciative of its condition (good wood, no dings or cracks, no rust, original) and liked the Buffington sight (they all knew what it was). So, one of these days (and soon) I will take the old girl out to the range and I will keep in mind your experience with targets at 100yds...



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Good to hear. It sounds like you got a good inspection, too. If they even knew what the Buffington sight was, they were way ahead of most people and probably knew Trapdoors better than the average gunsmith.

I wish the wood on mine was free of cracks and dings!

When you shoot it on paper, remember a couple of things. For some reason, the trigger feels twice as heavy when you are squeezing it at the bench trying to get a really good hit. It's strange to me. I know I've shot guns with heavier triggers, but the Trapdoor seems to take more concentration to keep pressing instead of giving a good yank.

And when it goes, that heavy hammer makes it jump a little before it goes bang. Have a good firm hold on it, or it may jump off target a little.

These things seem like nothing until you are sitting at the bench trying for a precise shot.

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Update: on the range with the Springfield yesterday - what fun!

Recoil is mild, frankly. I was on the 50 yard range and at 50 yards, I could dial in the windage, but had to hold about 15" under the target to hit it. I used the buckhorn part of the sight, and the peephole with the sight blade up and the blade as low as possible...seemed about the same for hits. I was more accurate with the peephole.

There is a definite jump and delay when the hammer falls...lots of moving mass, I suppose...but hits were good, given how I was aiming...

In deference to her age, I only put 20 rounds through, but they were enough to get a feel and get dialed in. I used Ultramax cowboy action loads, 405 GR cast bullets, about 1100 fps. Actual black powder-level loads with cast (not jacketed) bullets are hard to find at the moment. This was the only box I could find in trips to 4 different stores, but I've got some on back order at Midway.

Thanks for all your tips and notes, sure made it easier to understand what I was doing on the range.



PS - was with my stepson, and we had a mix of old and new. I had the Turkish Mauser and this was the other rifle we had with us: http://www.dpmsinc.com/AP4-308762-NATO_ep_125-1.html

Sure interesting to see the evolution of a battle rifle...if I had brought the Garand, we would have had every step along that evolutionary arc...

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Nice. Glad it went well. People either enjoy learning their idiosyncrasies or don't want to mess with them at all.

I plan to sometime spend a week or two at the range just fooling with the trapdoor. That should let me figure out little things like how it likes to be supported for best groups. It's made it pretty clear that little changes matter. The cleaning rod will jump out about an inch and a half on mine when fired, and if I don't re-seat it, the next shot will be a flyer. There are probably several things like that I've yet to discover.

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  • 3 years later...

Had the Springfield at the range again last week. It's just a pleasure to shoot. I still can't hit consistently with it, but reading up on the rifle, I suspect that the modern ammunition is a tiny bit undersized. One of these days, I'll slug the bore and be certain, and if I'm correct, well...I've been saving brass for just this circumstance and I'll be reloading for the old girl in the future. 

In the meantime, we've done a bit of remodeling at our house, and the Springfield now has a place of honor in our library. I'll still shoot it, of course, but it was just too nice to linger in the safe...


There are a couple of other articles of family history seen in the photo, including my great uncle's Merchant Marine hat. He captained Liberty ships in WW II, twice torpedoed in the North Atlantic. 

The Cavalry saber in the case was given to Captain William Barr, of the 101st Pennsylvania, on 01 August, 1863 for his promotion to Captain.  At Gettysburg, he was a First Lieutenant, and, well...you can imagine the occasion of his promotion...

He is my four times great Grandfather.  

Another heirloom too nice to linger in a safe...






You don't really need a spotting scope to know where a .45 went through the paper...


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Thanks - the range picture makes it look rusted, but it's really not. There is some rust/brown on the butt plate.  But the hammer and action still have most of the blue on them.

Either way, I am pleased to give it a place of honor in the house, where I just enjoy seeing it every day, instead of having it locked away in a safe.

I suspect it would prefer a load that's closer to the M1881 diameter...thanks for the recommendation!

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