First Pattern 1865 Allin Conversion – Trapdoor Springfield

As the US Civil War drew to a close, it was quite apparent to everyone that muzzleloading rifles were obsolete, and any military force wishing to remain relevant would need to adopt cartridge-firing weapons. However, the Union arsenals had a million or more muzzleloading rifled muskets still on hand. How to modernize the weaponry without simply throwing away all those existing guns?

The task was put to Springfield Arsenal master armorer Erskine Allin in 1865, and he devised a ”trapdoor” style of conversion to turn an old Springfield muzzleloader into a breechloader. He had the benefit of having seen the previous year’s extensive trials of breechloaders, but the final product was his combination of what he judged to be the best elements of the ideas available.

The result has long been known colloquially as the Trapdoor Springfield, and this 1865 model was the very first of them. It was still in .58 caliber, and used a rather complex extractor system. It would soon be revised to make improvements to it, and ultimately a .45-70 model became standard for US infantry and cavalry forces – and remained their standard until the adoption of the Krag-Jorgensen in the 1890s.

Yes thanks for tuning in to another Video on forgotten weapons I’m Ian I am Here today the Rock Island auction house I’m taking a look at some of the guns That they are putting up for sale in Their December of 2015 premier auction And I noticed that this one was in the Catalogue it may look like a trapdoor Springfield if you look closely but it Is actually a very interesting specific Type of trapdoor Springfield namely in 1865 variant the very first of the Trapdoor Springfield’s so the where this Comes from is basically the u.s. Civil War convinced pretty much anybody who Wasn’t under a rock the entire time that Muzzleloading rifles were obsolete Cartridges had been developed they Weren’t maybe perfect yet but it was Pretty obvious that that cartridge Firing breech-loading firearms were what The future was going to hold however the US military at the end of the war had Something like a million 58 caliber Muzzleloading rifled muskets in storage Left over from war production so they Saw that they needed to move to Something a little more modern but they Didn’t want to just throw away what were Literally a million guns that they Already had paid for that had been built That had all the work already gone into Them so a lot of this started with a Really big ordnance department test of

New rifle systems in January of 1865 They looked at something like 65 Different rifle systems for breech Loading rifles and spent time looked at All these guns and then the war ended And they kind of like threw the results Away and just stopped paying any Attention to it which didn’t change the Fact that the US Army had all of these Rifled muskets and they really needed Something more modern so you know in a Kind of classic example of Army Bureaucracy they did this huge test they Threw out the results and then just a Few months later in September of 1865 They realized well crap we need Something and they just took the one of The master armors at Springfield Armory A guy named Erskine Allen and gave him The job of creating a conversion so that You could turn these these muzzleloading Muskets into Breech-loading cartridge firing rifles So Erskine was a he was a smart guy he Was a talented machinist he was a Talented designer and presumably he’d Had access to a lot of these test rifles That the Ordnance Department had looked At so he didn’t take him long to figure Out what he considered to be the best Mechanism the best system for converting A breech-loading rifle and what he came Up with is what we today colloquially Called the trapdoor springfield you’ll

See why in a moment if you don’t already Know it is more technically called the Allen conversion after Erskine Helen now The very first version of this was named Or designated the model 1865 and a 5,000 Of them were converted from existing Muskets for Army Trials now they turned Out to be some problems with them they Weren’t a it was a good idea but it Needed some refinement and so the the Process developed and there are many Many iterations of the trapdoor Springfield which we won’t get into Today because what I want to do is take A specifically close look at this one Which is in 1865 one of those 5000 of The very first Trials guns that the army Made so let’s bring the camera back here Take a closer look at it and you can see How this differs from the the common Type of trapdoor that you almost Certainly have seen somewhere all right So the whole purpose of this conversion Was to save money the idea was to use as Much of the existing rifled musket as Possible so you had to spend as little As possible to wind up with a modern Weapon so so the design that earthscan Helen used was this what became called a Trapdoor design where you would take the Top of the existing rifle barrel and cut It away and mount this breech block Assembly onto it of course this lowers Into place and then lifts up out of

Place that’s why the weapon became known As the trapdoor because you had this Trapdoor in the top now this served as a Breech block so what you would do is Open the rifle up like this you would Then take cartridge and stuff it down Into the chamber here Close this breech-block behind lock it And then fire the weapon using the Existing hammer if we look at the rifle From the top you can see that there is a Firing pin right here spring loaded and That goes down in the breech block at an Angle and hits the cartridge the hammer And the lock assembly and the trigger Mechanism on these guns in particular on These first 1865 guns was completely Unmodified with the exception of Drilling out this area for the locking Latch this is all the no modification Necessary oh I should say with the Exception of flattening the face of this Hammer so the hammer here would have Originally had a recess in it to hit a Percussion cap they filed that flat and That’s the only modification to the Whole mechanism at that end of the gun When you fire the hammer comes down hits That firing pin right there which fires The rifle really it was a pretty it’s a Pretty ingenious it’s a pretty effective And reasonably simple to to do Modification now I had mentioned that What the army had stores over 58 caliber

Rifled muskets we normally think of the Trapdoor springfield as being a rifle in 45 70 caliber well that came later The first batch here were actually they Retained the same 58 caliber barrel and They used a 58 caliber rimfire cartridge The army then changed that to 50 caliber And then later to 45 caliber now some of The other changes the other differences Between this version of the gun and the One we’re more commonly familiar with One of the main ones is the extractor so When I lift this up you can see that There’s a thing moving right down in Here you can see that right there going Back and forth that is the extractor Looking at it from the other side here You can see that extractor moving back And forth that’s what pulls the Cartridge out when the trapdoor lifts All the way up it’s released and it Snaps forward ready to sit under the rim Of a new case you can see it’s going to Ride over the Tractor right there the extractor hooks Into that little recess and as I pull it Open there’s actually a series of like Gear cog teeth right here that push the Extractor back now this system would be Very much simplified in later versions Of the trapdoor but it’s a really neat One to look at on this 1865 pattern the Sights on the trapdoor would also change And improve significantly the sights on

This guy are the same as on the old Rifled musket so you just have this flip Up site with two different range options Here and your basic battle sight I think It’s pretty cool to point out that this Is very obviously a cut-up donated Rifled musket you can see it was Originally in 1864 musket and the front Half of that date has just been milled Out to make way for the conversion on These conversions we do have an 1865 Date right here on the lock plate that Was added and that is specific to these Early 1865 Trials rifles typically on Later trapdoors you’ll see you’ll have Dates more over here and you’ll also Have dates and serial numbers on top of The trapdoor the breech block itself Another element that was different on These from the later ones is that this Locking piece is actually manually Operated later on this would become Spring-loaded And quite a bit smaller so this little Locking bar right here goes into this Recess in the back of well the back of The breech assembly sort of so what you Do is pivot this all the way down into Place and then by pulling this down this Block is locked into the back of the Chamber and prevents the breech block From opening other element of that is When you drop the hammer the shape of The hammer fits over this locking lever

And also prevents it from unlocking and Coming forward or up so as I mentioned They made 5,000 of these for field Trials the trials went generally pretty Well but they did come up with some Areas where Mechanism could be improved and that Would lead to a whole series of howlin Conversions aka trapdoor Springfield’s I Think at some point we will do a video Showing more of that progression but Today we’re just taking a look at this 1865 model well thanks for watching guys I hope you enjoyed the video it’s not Every day we get a chance to take a look At one of the very first 1865 trapdoor Allen conversions the the later ones the Ones that were mass-produced are fairly Common today relatively speaking but These early trials guns are quite scarce So if you’d like to own this one Yourself if you have some other Trapdoors and you won early one to go With it or if this just strikes you is Very interesting well check the link in The description text below that will Take you to rock island’s catalog page About this rifle you can take a look at Their pictures and if you’re interested You can set up an account and place a Bid online today thanks for watching

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