I recently acquired a nice M1884 Trapdoor Springfield. Good wood and metal, very clean bore. Buffington sight in perfect working condition. Only problem was the receiver was cracked in the usual place - in front of the extractor groove. I thought, "No problem, I'll just take off the old receiver and install another one from the same serial number range." Famous last words! The barrel was a royal pain to remove from the receiver, but I succeeded with patience, a homemade action wrench, a little cussin, and a long soak in acetone and ATF. I then went to install the replacement receiver and it will not thread on far enough to line up with the index marks on the barrel or to bring the sights to the correct position. I cranked so hard that I bent my home made action wrench. The receiver and barrel are not indexing by about 10 degrees. Is the solution to carefully file some of the barrel face ahead of the threads? Or, am I going about this the wrong way? Thanks! Dave
Help with Trapdoor Springfield
- Thread starter davelid
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This sounds like a job for a lathe. Not only will the area that fits up against the action need to be relieved, but the rear of the barrel that fits up against a shoulder inside the action will also need to be relieved.
This will set the barrel back in the action and the barrel head space will need to be rechecked. Although most of the time these old barrels have excess head space anyway, but any time you move the barrel in an action the head space changes and should be checked.
It might be easier to try a different action.
SC45-70
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What SC45-70 suggested.
Get a depth micrometer and measure the distance from the breech face to bottom of the receiver where the threading stops. Do this at several points. Take the average. This will be you shank length.
Then measure the threaded portion of the barrel. That is the barrel shank.
If the thread portion is too short, you need to cut it back slightly and thread it (need a lathe) or sometimes just cut the thread it a wee bit more and relieve the shoulder (cut off tool is useful for this).
If you would like to do this yourself (and you can), take Machine Shop 1 and 2 at Trinidad State NRA Summer School. They'll teach you how to fit a barrel onto a receiver and then proof fire it (in what we called the Boom Room)
Get a depth micrometer and measure the distance from the breech face to bottom of the receiver where the threading stops. Do this at several points. Take the average. This will be you shank length.
Then measure the threaded portion of the barrel. That is the barrel shank.
If the thread portion is too short, you need to cut it back slightly and thread it (need a lathe) or sometimes just cut the thread it a wee bit more and relieve the shoulder (cut off tool is useful for this).
If you would like to do this yourself (and you can), take Machine Shop 1 and 2 at Trinidad State NRA Summer School. They'll teach you how to fit a barrel onto a receiver and then proof fire it (in what we called the Boom Room)
SC45-70 - Nice Trapdoor on your member pic! I had wondered about that - having to also trim the barrel threaded end as well. Then I would probably have to recut the recess for the cartridge rim.
4v50 Gary - Yes, definitely sounds like a lathe is needed and this goes well beyond my limited gunsmithing skills.
The first Trapdoor I rebarreled, years ago, went very smoothly. Everything lined up without any cutting. Not this time though. Rather than trying another receiver and, again, not having things line up, maybe I'm better off looking for a barrel with original receiver still attached?
Thanks for the info!
Dave
4v50 Gary - Yes, definitely sounds like a lathe is needed and this goes well beyond my limited gunsmithing skills.
The first Trapdoor I rebarreled, years ago, went very smoothly. Everything lined up without any cutting. Not this time though. Rather than trying another receiver and, again, not having things line up, maybe I'm better off looking for a barrel with original receiver still attached?
Thanks for the info!
Dave
Thank you Dave
Here are a couple bigger pictures.
It's a replica I built of a take down J P Gemmer trap door Springfield
SC45-70
SC45-70 - That is one nice rifle!
I thought that I would update you and Gary on my progress. After hearing that, "Trapdoor barrels always spin on and index.," from a couple of correspondents. I chased the threads on my barrel and all mating points with the tip of a pointed file. I also wiped everything down with acetone. In doing so, I found a couple of wire-like threads that came off the barrel or one of the receivers (original or replacement). I then added nipple/barrel plug anti-seize grease to everything and had at it. This time the receiver spun on just using a large crescent wrench (still took a little effort) and the index marks lined up and the sights and extractor are in the proper positions. I got the extractor and breech block assembled in the new receiver and the barreled action back in the stock.
I still need to test fire with a long string, but am waiting on a break in the snow (winter finally came to the northern Utah mountains).
Thanks,
Dave
I thought that I would update you and Gary on my progress. After hearing that, "Trapdoor barrels always spin on and index.," from a couple of correspondents. I chased the threads on my barrel and all mating points with the tip of a pointed file. I also wiped everything down with acetone. In doing so, I found a couple of wire-like threads that came off the barrel or one of the receivers (original or replacement). I then added nipple/barrel plug anti-seize grease to everything and had at it. This time the receiver spun on just using a large crescent wrench (still took a little effort) and the index marks lined up and the sights and extractor are in the proper positions. I got the extractor and breech block assembled in the new receiver and the barreled action back in the stock.
I still need to test fire with a long string, but am waiting on a break in the snow (winter finally came to the northern Utah mountains).
Thanks,
Dave
PS I was looking at the old receiver that was on my trapdoor - the one with the crack in front of the extractor notch - and on the underside it has a "C" stamp. I've read elsewhere that condemned receivers had a "C" stamped on them. If that is the case, I wonder if someone tried to rebuild a rifle with a condemned receiver (thus, the crack I noticed). Maybe my rifle is a "Bannerman Special"? Or, maybe the "C" stands for something else?
Dave
Dave
Thank you
Glad to hear you got it figured out.
I've rebarreled several trapdoors but I always use a new blank as the rifles I get always have a bad bore, and I prefer to build sporting rifles anyway.
All of the barrels that I've removed so far came off pretty easy, but I have a proper barrel vise and action wrench.
Good luck with your Trapdoor!
SC45-70
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