Hello.  I have a Spencer (repeater) that has an octagon barrel and is a single shot.  I read that after the civil war a number of companies acquired Spencer rifles and converted them to meet the demand of buffalo hunters.  Since this is a new acquisition, I haven't determined the caliber and can find no company information on the barrel.  Can anyone help me?  Thanks.

Over the years I've seen quite a few Spencers converted by gunsmiths to sporting rifle confuguration. Perhaps one of most well known was Gemmer. I'm not aware of any company who did this on a large scale. The action design greatly limits cartridge length, so there are few options. The most common is .56-50. There was a post-war .56-46 spencer cartridge developed for sporting use. I've not heard of a single shot only version. Does yours not have a magazine? Please post clear, close up photos.

Steve

Years ago I ran across one of those sporterized Spencers with a heavy octagon barrel, forend with a pewter tip etc. The bore near the chamber was mangled, like somebody tried to run a big tap in the bore. I mentioned it to Dave Thorn and he went and bought it.
Before he got flustered and re-sold it we kicked around the idea of making it a single shot. As near as we could tell, it would be no big problem to run a 50/70 reamer in and that is all you would have do. I don't think the magazine and feed mechanism would interfere with single shot operation at all.

The original poster has not come back to update us on his chamber cast or anything else. Maybe he lost interest    

Certainly the Spencer action greatly limits the cartridge length. But oddly enough, my M1871 Springfield Spencer 2 band rifle takes a longer than normal .56-50 cartridge. The cartridge length it takes is the same as the .50-45 carbine cartridge.  I'm guessing Springfield Armory just used the .50-45 reamer when making these. But the rifle will not cycle with the standard .56-50 length cartridge either. Rather odd.

While not really considered a Buffalo cartridge, the .50-45 loaded with 45gr of Goex 2F and a 350gr bullet out of my Spencer gives a little over 1100fps.  That's no slouch.  Here are the two side by side.

Spencer was a very talented inventor and patented several single shot rifles, in addition to his repeater. 
The single shot rifle, shown in his patent of 1873, easily handles a 45-90 length cartridge but I don't think that any of these rifles survived the Army trials.
Otto

The Spencer could be used as a repeater or as a single shot with the Stabler Cut-Off Device. Edward M. Stabler of Maryland invented the Stabler Cut-Off Device. It prevented the cartridge from feeding the magazine to the receiver by limiting the lowering of the breech block. The carbine could then be used as a single shot weapon. A few of the carbines manufactured by the Spencer factory, plus 19,000 of the 30,496 of the Burnside Spencers were equipped with the Stabler Cut-Off Device.

Chipmaker: Thanks a lot. It would not have occured to me. I did use a central ( 6 o'clock extractor ) but with hot Hornet rounds I am finding extraction difficult. 

I am thinking of building a full size one now in 45-70 gov or 45-90. I have modeled it and it might be that the latter case is rather long for it, keeping to the proportions of the patent. 

Now that I have nearly recovered from my meltdown, I am spending time ( maybe too much ) in my workshop, but my priority is to finish the pending projects I have before I embark on new one

This Spencer action was in the 1872 trials results published in 1873 with the adoption of the trapdoor Springfield. Here is some pictures that they published. Note that the hammer is much shorter than in the Patent.

Rodney,
Thanks for posting the pictures of the Spencer rifle submitted for the Army trials of 1872.
I was impressed by the differences between the patent drawings and the action frame shape, used by Spencer, in his submitted rifle. His submitted rifle looks more like a Ballard than a Spencer.
He also used a sliding extractor and I sure would love to see the details of how Spencer's extractor worked.
Mqabbi
Attached is a photo of a full sized Spencer single shot rifle. The breechblock drops down enough that the larger cartridges are easily chambered.
Otto

Chipmaker, I doff my hat. That is a beaut. VERY WELL DONE. It is amazing how both of us, a couple of thousand miles apart have done away with that unsightly lump at the bottom of the action in the Spencer    I have resized and superimposed your action picture in my CAD and found that your dimensions from the centre of the barrel bore to the top of the action is much bigger than mine. Hence my apprehension at 45-90 or 100. You have shown me a way out, but as my late wife would say, it would be cute to have a big brother and little sister combo, so I will stick to 45-70. 

Once again well done. Did you document your build and post it anywhere?

The Stabler Cut-Off Device is the part between the trigger and the block.
It is turned sideways or backwards  for either use as a single shot or as a repeater.

Yes it actually stops the block from dropping low enough for the bullets to be inserted above the block from the repeater tube.

I was just alerted to this thread and thought I would post. Here is a picture of my Romano Spencer SS in 50-90. I spoke with Larry Romano at length about this rifle and he told me he built it from the patent drawings. The story goes that Spencer sold the rights to his repeater to Winchester who made him sign a noncompete that prevented him from building another repeater. He built the single shot and submitted samples to the Ordinance Board for testing during the trials of 1873. I read that the Spencer did very well but it appears the fix was in and the award went to the Springfield. I understand that there are two rifles remaining from the trials located in a museum in Washington DC but I have not been able to locate them. Larry Romano is an excellent gun maker and a fine craftsman. His work it top notch and my rifle shoots exceptionally well. He is off the internet because some claim jumper bought his domain name and he is trying to get it back. I believe it is some fallout from the covid pandemic that caused it. Anyway, sorry for rambling. Here is the photo. Thanks, ratseye

Mqabbi Here is the information on the other two guns in the photo with the Spencer.

mqabbi
No. I didn't document my build or publish it.
Ratseye and those trying to find an original Spencer single shot rifle
The curators of the NRA, Smithsonian and Cody museums told me that they searched their collections and could find no examples of the Spencer SS.
Otto

I have the entire "1873 army report of testing rifle types" report on my computer that I found somewhere on the internet, but I can't find it now with any search engine or where I originally got it.  I would send it, but the pdf file is over 700 pages and is over 48 meg.  Doesn't lend itself to sharing very well.  The original file is good in that it is possible to blow up the page and get a better view of the pieces without loosing resolution.  There are some really interesting rifle actions in there that I have never heard of--Probably because they never came into production.    
Bruce

I must publicly thank Bnelson here for sending me the publication. I normally close my business at 18.00 my time. I was stuck reading it and have just arrived home 3 hours later than usual.    I think I will take it to Xerox and have them do me a bound volume from the pdf that I was sent. Once again thank you Bnelson