Springfield falling block?

[tbx-4]

Or, what to do with old gun parts...

A couple years ago I bought some Trapdoor parts from webfoot10 here on Cast Boolits. Used some, traded some and kept some for projects. I kept a barreled receiver because it was special in a couple ways and webfoot made sure I knew it was special and gave me a great deal on all the stuff.

https://i.imgur.com/JzrscNF.jpg

Both were in bright finish, which isn't real special. The receiver has an 1886 serial number and that ain't special neither. But looking inside the bore... Now that's special.

https://i.imgur.com/k3o9DqK.jpg

Now the other thing special was... well just lookie here...

https://i.imgur.com/Mxjn6FG.jpg

After unscrewing the receiver, a closer look.

https://i.imgur.com/E0cdA8m.jpg

After talking to a couple folks then contemplating what to do I decided this would make a good barrel for another action. So I turned the bad breach off and removed the threads.

https://i.imgur.com/HoWB9GQ.jpg

I then found these two Hopkins and Allen falling block 12 gage shotguns for sale locally and got a good deal on them.

https://i.imgur.com/A9qLPqY.jpg

[tbx-4]

I started to convert the bottom shotgun but found the hammer spring too light to fire rifle primers. Tried a few things but no go, put a nice dent in them but no fire. Will test on pistol primers and if that works will save it for a pistol cal conversion.

I did shoot a couple game loads through the top shotgun so I knew it was solid with good hammer spring.

I cut the shotgun barrel off at the front of the chamber. Ran a boring bar through it to remove the chamber taper then silver soldered the Trapdoor barrel into the chamber stub.

https://i.imgur.com/eM7kWQf.jpg

Welded a tab on the end of the extractor, dremel cut relief in the breach and fit new extractor. Also, recut chamber to proper depth.

https://i.imgur.com/McvMmtd.jpg

Made a new forestock and assembled it all together.

https://i.imgur.com/HpO4tPE.jpg

Got it all working yesterday, Moday and shot 20 rounds of 405 gr hard cast .459" boolits over 22 gr IMR4198 working on sighting it in. Loaded up 20 more rounds today and got things dialed in better. Might need to put a shorter front sight on because it still shooting a little low. But I was able to hit targets off hand at 100 yards.

Still need to decide how to finish it. Leave it original kind of well used look or steam the dents out of the wood and lightly sand and oil and re-blue the barrel and action?

[M-Tecs]

I've only seen and touched one Hopkins and Allen falling block shotgun. They are very cool.

I started to convert the bottom shotgun but found the hammer spring too light to fire rifle primers. Tried a few thing but no go, put a nice dent in them but now fire.

Shotgun and older BP rifle firing pins tend to be larger than modern rifles. Bushing and reducing the firing pin may resolve this with increased gas handling safety.

[tbx-4]

M-tecs,
H&A made falling block rifles and shotguns that used the same frames. I've seen some old advertisements that showed cal up to 38-55 but I'm not sure of 45-70. Jedman here has converted one to 50-70 and it works great so I thought I'd give it a try.

[lar45]

Very nice project, I picked up a HA 12 ga action with the thought of making a slug gun, but Rockwell tested the action and it came out in the B range.
I'd keep loads on the light side and watch the breach block for wear...

[tbx-4]

Lar45,
Yes, I ran across your write up on that project but there wasn’t a conclusion and wondered what happened. My smokless loads are in the Trapdoor range or a little less. I’m keeping an eye on it for stress and wear.

[John Taylor]

I don't know why trap doors were welded but I have had a couple come in with weld in the chamber. Was able to save one by lining the chamber. Several years back I had an H&A 12 gauge that I made into a 32-40. I didn't think to highly of the pin holding the barrel in so I made a tap and threaded the action. The actions are not hard at all and threaded very easy. The bolt thrust of the 32-40 is much less than a 12 gauge so I thought it would be safe.

[tbx-4]

John,
The breach on this barrel has not been welded on. It looks like someone took a die grinder with a burr head bit and gouged out two big divots or maybe just a lot of work with a dermal tool (?). Webfoot 10 who I got this from actually had at least another done the same way but not as bad. He was able to save the chamber by filling in the divot with brazing rod then lightly ran a chamber reamer through it to clean it up. Says it shoots fine.

He thought whoever did this was trying to make lamps out of the barrels.

So I'm using this without silver soldering the barrel to the frame like Jedman did on his 50-70 conversion of a similar H&A shotgun. So far I've shot 45 rounds with the load listed above through it. I've taken it down and inspected the take down pin and socket as well as inspecting the breach block and frame for any signs of stress or wear but haven't noticed any. Will be keeping a close eye on it though.

Like I mentioned in another post H&A used this frame for 38-55 and maybe even 45-70. I'm still trying to dig up old catalogs to find a list what calibers were sold.

I also saw an H&A falling block set on an auction site that had three rifle barrels and one shotgun barrel. It was the medium frame falling block action and the barrels covered were 44-40, 32-40, .32 center fire and 20 ga.

https://i.imgur.com/xtJ1Om9.jpg

[koger]

Very nice, thanks for taking us along for the ride!

[Jedman]

Just seen this post for the first time. You did a great job ! When I did my 50-70 conversion I made a complete new extractor for it and it was quite a lot of milling time. If I did another I would just modify the shotgun extractor. I just recently picked up a Remington take off barrel in 30-06 withe both front and rear sights for a good price. I am going to cut off most of the chamber end and turn it to fit my Hopkins & Allen M 922 and chamber it to 32 S&W long. I found the breech block in the 922 to have a round tipped firing pin and is only .052 from being on center for a centerfire cartridge. Strange to think that the factory would set up a 22 rf to strike nearer the center and just barely strike the rim from the inside edge but it fires 22 rimfire perfectly.
To make things easy when changing barrels I am going to turn the barrel shank on the 30 cal. Barrel .052 eccentric with the bore slightly below center so I don't need to raise the breech block by changing the link when changing barrels. The extractor will be made for the 32 S & W and will only require removing 1 screw to change out so very easy.
I am keeping the tapered barrel screw original as the breech trust on the 32 S&W is low and should be strong enough.
I have seen other 32 S&W long and 32 H&R magnums chambered on .308 barrels and it works fine.

As far as refinishing your old H&A rifle, I would wait and use it for a while and see if you don't like its character for looking like a 130+ year old gun. It sure looks fine to me !

Jedman

[skeettx]

Enjoying the thread
Skill abounds
Mike

[tbx-4]

Jedman,
Your 922 project sounds cool! That should be a fun rifle.
About refinishing, for now I'll leave it be like you said. Still working on loads. I should probably buy a 45-70 mold and start casting for it. The factory .459 hard cast boolits are not as accurate as I'd like them to be. They do work great in my Trapdoor carbine clone though.

skeettex,
Glad you enjoyed the thread.

[map55b]

Nice! Now you have a combo 45-70 and 12 Gauge. I like these old actions! I have a pair of the smaller frames and two mediums. One of those mediums was a 44-40 saddle ring. It was bubba'd good, but I plan to restore it. I've made the missing action parts and it functions once again. Here is what it looked like when I found it.

242729

This is what it is supposed to look like. ...and will again one day.

242730

[map55b]

.....

So I'm using this without silver soldering the barrel to the frame like Jedman did on his 50-70 conversion of a similar H&A shotgun. So far I've shot 45 rounds with the load listed above through it. I've taken it down and inspected the take down pin and socket as well as inspecting the breach block and frame for any signs of stress or wear but haven't noticed any. Will be keeping a close eye on it though.

....



There is very little forward thrust on a straight case, just the resistance of the bullet trying to exit the barrel. If you were worried about it, you could make a new retainer pin/bolt out of 4140P. If the pin was only .25 round and .24 tall it would handle ~1700 lb of force.

[Jedman]

There is very little forward thrust on a straight case, just the resistance of the bullet trying to exit the barrel. If you were worried about it, you could make a new retainer pin/bolt out of 4140P. If the pin was only .25 round and .24 tall it would handle ~1700 lb of force.
I dont think you can think of it as forward thrust . In the millisecond after firing where pressure is building it is applied to everything in relation to the cartridge. The brass expands to grip the chamber but that is just some resistance, the rear of the case is mashed against the breech block and closes any gaps or clearance, pressure starts pushing the bullet down the bore and same thrust that is on the breech block is also shared with trying to push the weight of the barrel against whatever means holds it into the reciever.
Lucky that it isn't sustained for more than a millisecond or parts would break. All of the different early model guns I have owned from 22 boys rifles to shotguns that use a barrel attachment like a grub screw eventually get loosened or even sloppy from that forward thrust.
It was a simple way of making the gun takedown and a cost savings to manufacture it without threading the reciever or the barrel.
When you look at a gun such as the Stevens 44 1/2 that was built plenty strong for hi pressure cartridges of the day they threaded the barrel into the reciever plus added a takedown screw as the barrel was only threaded in hand tight.

Jedman

[ascast]

I think those actions are well known to crack, break with smokeless pressure. Finding one that it not cracked is more of an exception. Be careful.

[john.k]

They were cheap guns,and made takedown to be used by a bicycle rider,or train traveller.......anything mechanical wears out or breaks eventually..........survivors of a bygone age,when most people had very little money.

[tbx-4]

I think those actions are well known to crack, break with smokeless pressure. Finding one that it not cracked is more of an exception. Be careful.

And this is why I load my 45-70 smokeless loads to black powder pressures or less.

But to say they were well known to crack/break I'd ask if you could show reference. I'd be very interested in any information describing the failures. I know of the Stevens actions of the same era and their inherent weakness. Mainly because they are not true falling blocks but have not come across any reference to H&A falling block failures. If you could provide such it would be greatly appreciated.

Along the topic of wearing out an action I have torn both of these down and examined them. They have been used, a lot and well into the 20th century and doubtless with smokeless shot shells. It all looks to be normal wear for their age. The older of the two shows more wear as can be expected. Even though the older action has a weaker hammer spring none of the parts in either action show signs of eminent failure. Pins, holes and frame show no abnormal deformation. The function of both actions is not hindered in any way as happens from excessively worn parts. Both actions function as designed except for the weak hammer spring as mentioned.

Now this subject can garner a heated debate but I hope all here will discuss their views as dispassionately as possible to keep it a pleasant thread for all to read.

[Chev. William]

U have also heard Stories about the Whole range of Black Powder Era Rifgle actin sbeing Weak, Subject to near instant breakage if used with Smokeless Powder, Etc.: BUT, I also have not seen any period records of such happenings.

In my own Experiments I have Fired a Grade 4 Nail Gun .25CAL enclosed in a piece of half Hard Brass tube, as a chamber sleeve/bushing, in a Stevens 1894 Favorite chambered for .25 Stevens Long behind a 63 grain lead bullet.

In This Case the Headspace opened up because the original Breech Block Pivot screw bend under load (it rec eived about 1.4 times the Force applied to the Breech Face due to receiver Geometry).

Nothing Broke.

The Blank's case ballooned into the Expanded Head space and was pierced on its top rim edge by a blow out.

The Bullet did exit the Barrel headed downrange.

I had some new Pivot screws made from New High strength Alloy steel High tensile NAS Bolts to replace the soft Low Carbon Steel originals.

I backed off to Grade 3 Nail Gun blanks for my Breech seating experiments and have not had any problems since.

Chev. William

[richhodg66]

I started to convert the bottom shotgun but found the hammer spring too light to fire rifle primers. Tried a few things but no go, put a nice dent in them but no fire. Will test on pistol primers and if that works will save it for a pistol cal conversion.

I did shoot a couple game loads through the top shotgun so I knew it was solid with good hammer spring.

I cut the shotgun barrel off at the front of the chamber. Ran a boring bar through it to remove the chamber taper then silver soldered the Trapdoor barrel into the chamber stub.

https://i.imgur.com/eM7kWQf.jpg

Welded a tab on the end of the extractor, dremel cut relief in the breach and fit new extractor. Also, recut chamber to proper depth.

https://i.imgur.com/McvMmtd.jpg

Made a new forestock and assembled it all together.

https://i.imgur.com/HpO4tPE.jpg

Got it all working yesterday, Moday and shot 20 rounds of 405 gr hard cast .459" boolits over 22 gr IMR4198 working on sighting it in. Loaded up 20 more rounds today and got things dialed in better. Might need to put a shorter front sight on because it still shooting a little low. But I was able to hit targets off hand at 100 yards.

Still need to decide how to finish it. Leave it original kind of well used look or steam the dents out of the wood and lightly sand and oil and re-blue the barrel and action?

I really like the looks of that rifle! Not much else to contribute to a very interesting thread, but I hope you'll post results of how it shoots as you work with it more.