The Borchard was first designed by AL Story for the .50BMG and works just fine with it. We had to modify it for the rimmed case of the 12GafH. It will handle any .50BMG load imaginable. I'll take some close ups of the extractor so you can see what I'm talking about. Basically its no different than making a extractor for a rimless case on a rolling block. This action is hell for stout and probably will exceed a Mcmillan for sheer strength. The reason I went with it was its extremely easy to get a rimmed case to work with it and not be hampered by cartridge length. The 12 Gafh wont even fit in a Mcmillan.-Rob

And it is wide enough and stout enough,
if I had one I'd put our 4bore case in
it. It is able to take bmg loads way
over 200,000 psi, by my calculations.Ed

Any chance of us getting one? Where would we start looking? Thanks.

Yep, I want one.
How could such a desirable action be in such poor demand that they are not being mass produced?

A hefty price(over 3 grand), and a lot of guys aren't into
singleshots or falling blocks. Me I like them,
and am working to build my own someday for 2/4 bore.

Finally got my 23,000 ft lb gun in an action
and stock. My 700HE 3.87" case, max over 330gr powder.
It is barrel I did the load testing with it locked
onto an I-beam. Gun is 27 lbs.Ed

Rerun:

Mr. Bradley is a "Rifle Loon" of highest order, and that is the highest complimentary flattery that can possibly be bestowed. But flattery gets me nowhere:

Rip-That is a neat looking old style gun.
What does it cost for action.
Extremist-- Borchardt Rifle Co, Al Story,
phone is 505-535-2923 Ed

Ed,
I wish I knew. Mr. Bradley did a "one-off" from scratch. It is very obscure. That page from Very High Power is all the info I have.

The Jumbo Sharps-Borchardt would be a better action, eh? Sounds like more than one of those was made.

I would not pass up a Jumbo Sharps 1874 if I tripped over one, however.

Al pretty much made mine by Hand. It took literally hudredsof hours of machining and it shows. I dont know how may he has made but my guess is under 30. These actions are not very complicated and with a good wire EDM it would not be too tough to cut out the block and sliding breech block from 8620. After that its pretty uncomplicated machining. Maybe someday soon I'll spring for a wire EDM and see what can be done. I've always liked the lines of a scaled up Martini Henry.-Rob
Its possible to open up many actions to fit a .50BMG or a shortened version. The Martini Henry comes to mind readily, but actually having it hold up to a full .50BMG is another thing.

On my falling block projects I have rough
models in 12ga/bmg size and 4bore size.
Once I get PH,etc, and my 585 and 700
cartridges going this fall and winter,
I hope to get back to them. Get extra equip
put in is the hope.ED

Hello everyone, to Mr. Hubel, RobGunBuilder, and Safarikid. All of you are a great inspiration, I love how far you can safely push the envelope.

I intend shortly as a graduation gift to myself to put together twin rifles in .375 H&H, and .600 overkill, I think they should handle anything I ever come across, BigFoot and all

Mr. Hubel, you may be interested in a firearm I had the privilege to fire many times when I was still in the Army.

One of our retired armorers was a WW2 trained Navy machinist who later transferred and retired from the Army. He made all sorts of guns and modified others. One of the neatest for me was a enlarged all steel falling block scaled up to fire 40MM grenades, it would fire both Infantry rounds and MK19 rounds, (higher powered) with barely any recoil do to weight.

It was a blast to shoot, he called it his chubby, when we got to the range he would always say "just let me whip out my chubby". He was a great guy, passed many years ago.

He made two of those and I have emails out trying to track down one, if I get a response, I might just have to forward it to you and let you go nuts, it would be interesting.

Be nice to find those falling blocks.
Work for my 2 ga. Thanks for info and good
luck finding it. Ed

Mr. Hubel

Thank you for the fast response, he was a great guy, a wild one too, he sorta kinda, accidentally on purpose maybe, blew up a whore house in Vietnam, story for another day.

He was always a big fan of the schuetzan (?sp)rifles but a Government pension and many children and grandchildren money didn't go to far so he made most everything he needed.

I still have the engraved trade gourget he made for me when I got tabbed out for the third time.

I'm in contact with a couple of his children and we'll see what they know about the collection, thanks again.

I wonder how many folks would be interested in actually buying a large falling block CAPABLE OF HANDLING THE 12GAFH or a 2 Bore if the price was under $2000? I may be seeing a CNC EDM in my future.
More recoil than brains- Good to hear you are going to get a .600OK you'll have a blast with it. Best Big Bore out there if I say so myself.-Rob

RobGunBuilder, I would certainly purchase a large falling block, the 12ga FH would be an amazing survival type firearm, (my Hobby)everything from light dove loads to tank busters.

Once I figure out just what my monthly payment on my school loan is I'll be speaking to AHR about the two rifles.

I am extremely impressed with the .600 ok, you are to be commended sir, have you considered some type of penetrator round like that used on a tank? You could probably market it to Police depts who want barricade breachers without the range of a .50 BMG round. Just thinking out loud.

Rob

We will be watching

Rob,
If you can build a falling block action capable of handling the 12GFH for less than 2K, I want one. Yes that would be quite the survival tool: 12-Guage FOR Hell

Morerecoilthanbrains and RIP- Look at the subsonic .45 thread for the latest in dart stabilized penetrator thinking. I have a concept that needs proving out, but yes in .600ok and 12GAFH there is a aluminum carrier penetrator in the works. Dart stabilized 12GaFH rounds should be easy to do. However I need to get some actual range results first. This is much trickier than I thought.
RIP-I see a EDM in my near future. Once I have one cutting out falling block actions is a piece of cake. I now have a good heat treater and just purchased EDM CADCAM software What I'm learning though is machine time and supplies, materials, cutters etc adds up fast. I actually wont know till I try it. The good news is I have very little overhead to absorb.

My local gun emporium has an H&R Ultra Slug 12-guage 3" single-shot with fully rifled fat barrel.
Should I buy one of these as a warm up for the 12GFH?

Rip-That is the way to get in recoil business.
You can start with our hopped up plastic case loads,
or get chamber lengthened to 3.5" and get brass cases like
I have coming from RMC. I think 600gr at 2400
is doable in NEF. With 3.5 RMC shotgun primered
cases, using 4227 and 4759 powders. VV110 also.
I am having a 3.5" reamer done to send out on
loan for guys needing to deepen chamber.Ed

Ed, that H&R "Ultra Slug" looks like fun.
What 3-inch brass would be best for highest pressure 12-Guage slug loads, and what would that pressure be for that combination of brass and gun, in your estimation?

I will get one of those and measure the TWIST of the Ultra Slug. It is 10.25 pounds "dry" (thanks to surestrike for that terminology). Mostly all rifled fat barrel weight.
Adding the scope and a full ammo carrier on the butt ought to get it over 12 pounds.

About time I started shotgun reloading.

The twist is 1 to 35". And put on a thick pad.
The 3" thickwall RMC brass cases in 3" will
do fine. Ask for thickwall version.
Using 600gr Dixie slug, start at 95gr of
4759. Use a card and wads, so that truncated
nose of the slug protrudes from case. You should be able to go to 105gr. pressures will
be 15-20,000 psi.Don't use soft slugs.Also
our guy down south will soon have jacketed
730 12ga slugs.Ed

quote:

Originally posted by hubel458:
The twist is 1 to 35". And put on a thick pad.
The 3" thickwall RMC brass cases in 3" will
do fine. Ask for thickwall version.
Using 600gr Dixie slug, start at 95gr of
4759. Use a card and wads, so that truncated
nose of the slug protrudes from case. You should be able to go to 105gr. pressures will
be 15-20,000 psi.Don't use soft slugs.Also
our guy down south will soon have jacketed
730 12ga slugs.Ed

Thanks, Ed. I shall proceed on this in my usual slowpoke fashion. The .458 Ruger Max will have to wait!!!

Ed- Check out the 12GaFH aluminum carrier on the subsonic .45 thread. Whats your guess, fast or slow twist works better? I stuck a .50BMG 750 amax in the center for effect. My plan is to use Tungsten carbide .5 inch blanks. Its a bore rider design for rifled tubes, but I could always mod it for a smoothbore. I also have some thoughts about adding pop-up fins.-Rob

Korean-War era air-to-ground rockets used pop-out fins. I know because I was head of the local Rocket Club and another kid found one washed up on the beach and brought it to me. But the fins were deployed by the spin on the rocket.

The rocket was about 3 feet long and 5 inches in diameter, aluminum tube. There were 4 fins, each rectangular aluminum about 5 inches long and 1.5 inches wide. Each fin was hinged at the back of the rocket, so the rocket could be fired out of a tube: the fins folded in behind the rocket neatly.

Rather than having only one rocket nozzle, this one had four separate nozzles. Each nozzle was tilted about 20 degrees to the rocket’s axis, so that they would impart a spin to the rocket as it left the tube. The fins swung out only by the centrifugal force of the spin. There were no locking mechanism on the fins to keep them deployed.

Im going to adapt the 12gaFH concept to include some fins. I wonder though if the spin will be so fast that it rips the fins off. Might work better in a 12Ga with a much slower spin imparted by a rifled choke.-Rob

A one twist in 7 inch barrel at Mach 1.0 (1050 fps) means 108,000 RPM. So the fins would have to be pretty well balanced.

Dart stabilization implies “fins†of course, but the fins are not what we normally think of when we say fins. The extended body aft of the CG does the same job as fins would do.

I’m looking at the 12GA projectile. Is 0.743 a safe OD to use in my crude calculations?

The long body will take care of the stability.
A regular 1 to 35 Nef may do it. I'm sure that our
1 to 20 barrels will. The crux is to get real tight
concentric fit. That is why most deals like this in use
nowadays uses plastic sabots for a little compression to
get a centered grip on the bullet to spin it ok.
Sabot plastic is real hard, and slightly oversize
to compress to get a good lock on the bullet.
If you can get tungston insert to fit super tight
the aluminum or other alloy you mention should work.
Was the insert going to be flush with carrier front?
Rob, hat carrier you built, was the plan to use
subsonic or high speed like our case can do?
If you'd like I could test the aluminum deal in my
well seasoned barrel. I don't know how the
aluminum works in relation to steel rifling,
IE does it have lubricating properties like copper.
See pic of the my bullets in Federal sabot.Ed

Henry22LR- No the 12 GaFH is .729 and the borerider section is .719.
Ed-The 12GAFH application is full power! The only info I've ever seen on aluminum is from Gerard who says his aluminum bullets worked just fine at 4000fps out to 100 meters and I take him at his word. This is a bore rider design so there is only minimum engraving going on. I think some moly coating on the bullet isnt a bad idea anyway. The tungsten carbide inserts are a thermal interference fit so they wont come out and are completely concentric with the carrier. I'm going to order some material and make a dozen and send you some . It will be two weeks though. I'm going to try them in my encore/paradox also.-Rob

Rob- I'll test them as fast the Savage will
go. I also have the real long smooth barrel
on the 87 to try a couple to see if they
are nose heavy enough to stay straight like
the Brenekkes do with locked on plastic wad,
that I test in the 87.

The guy down south also has a hollowbase smoothbore
design with a jacket. The jacket comes to within
1/8" of lead base, to allow expansion to fit smoothbores tight. Something to test down the road. As well as his
jacketed ones he is making now. Ed

Rob and Ed:

[/QUOTE]

I picked up a MEC SUPER SIZER MODEL SS77 at a local Gander Mountain today, like the one in Ed's photo. Also got the latest RCBS and Lyman Shotshell Reloading Handbooks.

Time for me to alleviate my ignorance of this reloading specialty.

Add a MEC "progressive" shotshell press, and what else do I need for 12GAFH reloading?

Are there any FL dies made for the 12GAFH 3.85"?

Source of chamber reamer?

Any brass available?

I have not read all of this thread, but I have scanned through it and printed it all out to paper in a binder for future reference, as well as Ed's thread at:
www.ammoguide.com

A recap on components (availability, prices) would not be out of line here on page 21, would it?

Thanks in advance.

Dove season is coming real soon, and sadly, I doubt I will have a 12GAFH for dove shooting, this year. Maybe I can get in some rabbit hunting with one soon. Just waving a 12GAFH shell at a rabbit might scare it to death.

If you have a machinist with a lathe you can run a boring bar into the chamber and lengthen it to 4.0. I do have a reamer if that fails or is too troublesome. The chamber can be lengthened by hand. I have made sizing hand dies myself as well as a custom bullet seater. I screw off the rimmed base and screw on a homemade.50BMG rimless base for priming etc. Some use a steel rim but I've found a brass rimless base will work fine with a std.50BMg shell holder for reloading. I
have found that 50 gr of bulleseye over corn meal with a soap sealing wad will blow out .50BMG cases directly to 12gafH with only 5% failures. Youll need to trim to length though. Make a .729 pilot.-Rob

quote:

Henry22LR- No the 12 GaFH is .729 and the borerider section is .719.

What is the OAL length of projectiles I should be using in my crude dart stability calculation for 12 GaFH?

I want to run a bunch of peak dart-stability vs. projectile grains for a variety of materials like alum/lead, alum/tungsten carbide, ZA/tungsten carbide, ZA/lead, etc., both with/without wasp-waist. You never know what might be “bestâ€â€¦

Has anyone actually FOUND any ZA bar stock yet? How about pure zinc as carriers?

Rob and Ed:

As I run all these 12Ga dart stability graphs, do you want them posted on this Thread or over on my “45 Subsonic Shooters†Thread?

I don’t want to possibly pollute this Thread with all that graphical data unless you two want it here. Ever since my “Torque Recoil Reduction Deviceâ€, I’ve been extremely cautious about my possibly polluting this Thread.

Henry if its 12GaFH related feel free to post it here. I simply scaled the .45 cal dart to 12 ga and my carrier is 3.25 inches long. Bore rider section is .719 and groove is .729.-Rob

Rob, I’m also curious about short bullets with dart stability, if they are possible. I’ll be running some cases on your 600 OVERKILL bullet and posting them here, unless you object. ( if you object I won’t post ANYTHING on 600 OVERKILL, because I consider it your property).

Estimating the 600 OVERKILL as a simple cylinder of diameter 0.62 inch and 58.32 grams, I get overall lengths of 1.32 in. (copper) and 1.39 in. (brass). These sound a little short, probably meaning they aren’t simple cylinders. Is 1.6 inches a better OAL projectile length for a 900 gr 600 OVERKILL? I want to see how much dart stability we should get with a tungsten carbide front and aluminum rear. My simulation is pretty crude, but predicts dart stability probably within 10%.

Henry- They are 1.605 to get 900 gr in copper and 1.650 in brass. Thanks for the request to post and go ahead and do so. I have no objections.
Just got some Tungsten carbide rod and learned to cut the stuff with a very expensive diamond wheel. Whew!-Rob

Yeah, the lapidary guys cut large thin slabs of agate using thin 12 inch diameter copper discs (“wheelsâ€) run at low speed. They use a flow of a thin slurry of diamond rouge powder mixed into kerosene or water. We used a small band-saw, with the blade replaced with piano wire, same kind of slurry, to “dice†lead-zirconate/titanite blocks for piezoceramic transducer production. These are messy processes.

I really don’t expect much dart stability from the 600 OVERKILL, because of the small length/diameter ratio, but just thought I would verify my suspicions. Maybe we should look at some of the WORLD CLASS ACCURACY 30-something cal benchmark projectiles. Maybe some of those, made of aluminum but with a tiny little tungsten tip, could equal the grains of the highly accurate bullets. Then we could fire them smoothbore, to see how close we get to the best of the spin-stabilized accuracies.

Just so much to try…

Henry the cup point boreriders were never meant for dart stabilization. HECK AT 25-50YDS THEY ARE MEANT TO BE SIMPLY A DEEP PENETRATING PARTIALLY EXPANDING compromise between a brass solid and a woodleigh mini bomb( smoking ball of lead in 2 ft). No finesse just brute force killing power.Just meant to knock a TREX flat on its ass.-Rob

I am sure I will be able to explode an H&R/NEF ULTRA SLUG by using readily available components, especially if I rechamber it to 12GA-3.5", even with the plastic, high-brass hulls, though I will be on the lookout for all-brass hulls, and genuine 12GAFH components eventually.

I must crawl with the puppies before I run with the Big Dog.

Has anyone slugged the barrel of an ULTRA SLUG?
Is it .729"/.719" groove and bore? I need to fine tune my proof load slugs.