Primer tubes are only show ignition gains in artillery
cases. And not much even then.
You guys needing chambers lenthened, Rob has all the stuff
to get you a good long chamber.

I fired my mono-blocked NEF today with a 585HE. Barrel is 32
inches and the gun is weighted to 15 lbs. Thick pad.
I have cone breech as this case is belted with thick base.
I'll have a pic of gun later. Gun is still tight after testing.
I can take out cases with my fingers if they don't stick.
First bunch 650gr today, with no extractor. The HBMG, WC-860,AA8700,
Retumbo, Magpro, RE25, W-780 loads fall out of the chamber,
with my fingers.If I tip gun up they fall out.
Top speed with RE25 and W-780 is over 2400. Now I knew what
to load them at because I have tested this case in 3 other guns.
This is a prime example of a case working so easy
due to proper side taper.Ed

Well I've made some more progress on the 12GaFH Double rifle. I've given the quarter Rib a great deal of thought and came up with the idea of extending it back and machining in a 1/2 inch groove to completely cover the old Zabala rib section. Once the tab is welded to the barrels from the bottom and the rest of the new rib soldered in place the old rib would not only be invisable but the whole gun will look professionally made. If the barrel to monoblock peening works as planned, even the seam between the monoblock and new barrels will be nearly invisable. The quarter rib is actually quite complex to make as there are multiple complex angles involved. To do this by hand would probably take 50 hrs of work or more. I spent a entire day taking measurements from both my Zabala and a .470 Nitro Express DR from Butch Searcy to develop the design. Finally, I wrote a AutoCAD prgm and proofed it on the Mill. Yesterday I fired up the mill, loaded up a 10X3X1 piece of 7075 Aluminum , checked the pgm one last time and fired her up. Everything looked good and it ran perfectly for 4.5 hrs. Had to flop the plate to do the other side, but basically it came out perfect and only needed clean up with a file. The fit is so close that a tiny bit of solder will make all the joints invisable. Now that I know the prototype in AL works, I'm goin to load up a 4140 plate tomorrow and make the real thing. My goal is a completely reproducible 12GaFH that can be made from a Zabala 10Ga. Now that I have the Quarter rib, I can cut out the top and bottom ribs to match from some 4140 tubing I found. Next I have to design a elegant front sight and start thinking about regulating the monster.-Rob

Rob that is gorgeous, beautiful work.
The sight ramp is a perfect shape.
They sure are a nice gun without being
too gaudy. Ed

dang Rob.. i am going to go throw a bunch of my guns in the trash, after seeing that

Rob,
Great work!
That's a great project, worthy of the effort.

I see your Zabala has sideclips, Greener crossbolt, and action bolstered like The Hulk.
Could you spell out that particular shotgun model designation and do you know when it was made?

RIP/Ed/Jeffe- Thanks for the nice comments.- I dont know too much about zabalas other than its the Mercury model in 10Ga with 30 inch barrels. I'll look for additional markings.
The ramp was a complicated project to design. Its purpose was to hide the remains of the original zabala top rib which you cant remove without totally screwing up the looks of the gun, and to make a good looking quarter rib that would also not interfere with the forearm hanger. Lots of things can go wrong and this is my first try at deep profiling. Ah the miracle of Al prototypes! The only change I found I need to make is the depth of the underside cut that covers the old ramp. CNC is way cool and I'm now really getting Dangerous with it. Given that I'm self taught! When you hold the gun up that angled ramp looks real nice and seem to want to drive your eyes to the sights. -Rob

Rob,
When you start test-firing "The Hulk" please use only one live round and a primed empty case in the other barrel.
After a dozen or so single-fires, alternating barrels, with no dent in the contralateral primer, go ahead and double load it.

RIP- Yes, gotta think carefully about the almost certain double event. If you shoot doubles long enough it will happen.Thats why most doubles show more wear on one barrel than the other! A double in a .500 NE can take you by surprise.A double with the 12GaFH that took you by surprise could be disasterous! I think a double at the 8000 ft-lb level would hurt big time. I'm gonna get Bigdoggy700 to regulate it for me.-Rob

Rob,
You gotta give the double 12gaFH a name ... "Satan" comes to mind ... Double Devil ... "El Diablo" ... Spanish shotgun action, after all.

"!Que diablos! El Diablo! Yee ha!"
So says Zabala Hermanos from the Happy Hunting Ground.

RIP- Great thinking- El Diablo it is!Thanks for the idea. I was thinking "BAD KARMA" myself.-Rob

Yeeha!
My next 12GaFH shooting will be Rob's Brass Darwin 1385-grain slug, in RMC brass with 209 primer and RL-17.
Chronography of any loads for 12GaFH is diabolically important.
Yeeha!

Dos Diablos

Sorry for the crude drawing on a Starbucks napkin but why not make an aluminum sabot for the short stubby 577 and 600 woodleigh bullets?

The aluminum walls would be 72 thou thick on the 577 and 54 thou on the 600 and would break open or expand on impact and not affect performance much. might just be a good option for 12 GFH softs. What say Ye? I think the rifle engaging should put a good enough preasure on the bullet to get it to spin with the sabot.
Use the same program code for the CNC minus the hole diameter.


900 grain woodleigh 600

RIP, just out of curiosity, did you happen to run RE 17 in quickloads? Just wondering, I should have some components in the next few weeks. Good luck!!

Msheik,
It is easy to get lost in this long thread.
Such high pressure as 55Kpsi would only work in a heavy, strong action, below is just a cautionary listing.
This is from the last page:

12GaFH No.1, 22" barrels, 1085-grain Brass Darwin, 10.5# gun:
(If the rifle weighs 14 pounds instead of 10.5 pounds,
then multiply the stated recoil-energy and recoil-velocity by a factor of 10.5/14 = 0.75, and so on for any weight gun ...)

RL-17 233.0 gr:(101.7% fill)
2371 fps
54,247 psi
13,539 ft.-lbs.
Recoil: 383.77 ft.-lbs. @ 48.4 fps

RL-15 220.0gr:(100.7% fill)
2352 fps
54,813 psi
13,330 ft.-lbs.
Recoil: 367.75 ft.-lbs. @ 47.45 fps

RL-17 is Velocity Champ in QuickLOAD ... and can be set off reliably by a CCI-209 primer?

And some low pressure loads with the heavy slugs:

12GaFH No. 2(09) Everlasting
1382-gr Hard Lead Darwin
24" barrel, 11.5# gun:

RL-17 160.0 gr.: (69.2% fill)
1578 fps
20,931 psi
7637 ft.-lbs.
Recoil: 225.90 ft-lbs @ 35.54 fps
89.7% Propellant Burnt
25.0% Ballistic Efficiency

RL-17 166.0 gr.: (71.8% fill)
1637 fps
23,024 psi
8224 ft.-lbs.
91.7% Propellant Burnt
26.0% Ballistic Efficiency

Easy enough with a good muzzle brake.

Nitro card, fiber wad, and BPI-BPGS gas seal could be used to fill the case, CCI-209 primer, and no starter powder.

Hoping to shoot some sort of RL-17 loads this weekend.
Last weekend was all "Mother's Day."

Will be experimenting with the RL-17 light loads using 1085-grain Brass Darwins.
Will run those through Quickload and add on here. Should be O.K. with fillers suggested above.

I wonder if there is a update available from quickload as I have a older version that doesnt include RL-17. For the new guys, please bear in mind that we are holding NEF loads to less than 35KPSI. Some of those loads RIP posted should only be used in a much heavier constructed gun.

Finally, I made the upper and lower ribs for DOS DIABLOS (12GaFH DR) yesterday. Gigantic PIA that took way longer than I ever imagined. Today is designing the front sight and maybe a prototype. Pics once this is done.-Rob

RIP, sorry, should've checked on the other pages, I didn't remember you running it with RE 17. Thanks for it though. I'm interested to see how RE 17 performs with the 1085 brass Darwins. I've got a few of those coming from Rob as well to play with.

Rob, can't wait to see pics of the double. Are you going to put it up for sale or keep it?

Rob,
I went here:
www.neconos.com/details3.htm
and saw this:


NOTE!! If you have versions 3.0, 3.1, 3.2, 3.3 CD versions, you can purchase a new data update that will update data and add new powders, cartridges and bullets to your existing version.

If you have 3.0, 3.1 or 3.2 and are planning on using a VISTA machine you must install a VISTA compatible QuickLOAD disk. Send in your old CD and we will replace it with a Vista compatible CD (also works with Windows 98SE, ME, 2000 and XP) for $14.95 plus S & H.

If you have a floppy disk version 2.7, 2.8, 2.9 you can upgrade to a VISTA compatible 3.4 CD for $50.00 plus S & H (usually $7.00 in the USA). Send us the original floppy with serial number on it to the address shown on the left so we can burn a CD for you. This is done in Germany and then sent to us in California. We send the new CD to you. Please allow 2-3 weeks. No need for special packing. Just put the disk in an envelope.
NECO

108 Ardmore Way

Benicia, CA 94510

Above is a snippet from QuickLOAD.
The perfect load for DOS DIABLOS. Thanks to Tyler for helping Rob with the name of the beast.

1085-grain Brass Darwin
22" BARREL
RL-17: 179.3 grains
78.3% filling of net case volume
1800 fps
24,436 psi
7804 ft-lbs KE

14.0-pound gun recoil:
167.22 ft-lbs
27.72 fps

And if you have 24" barrel on an NEF, here is the perfect load for that:

1085-grain Brass Darwin
24" BARREL
RL-17: 175.2 grains
76.5% filling of net case volume
1800 fps
22,982 psi
7804 ft-lbs KE

11.5-pound gun recoil:
201.04 ft-lbs
33.53 fps
Assuming a VAIS Brake eliminates all but the bullet generated recoil, maybe over-optimistic:
132.20 ft-lbs
27.19 fps

I am still waiting for 3.85" RMC brass and lead slug sizer(s).
I will use the 3.5" RMC brass and seat the 1085-grain Nohbozo Brass Darwins out as long as practical.
209 primer.
Fiber wad and nitro card to fill the case.
No plastic gas seal experiments just yet.
Will try these powder charges:
160
166
172
175.2-grain loads of RL-17
I have QuickLOAD velocity and pressure comparisons of the above powder charges.
Will see how close they are to predicted velocity over the chronograph with my "El Diablo,"
the 11.5-pound 24" NEF-er with VAIS brake.

Pictures of progress on "Dos Diablos" are eagerly awaited.

QuickLOAD says that with RL-17
going from 24" to 22" barrel you lose about 40 fps.
You get about 10 fps per grain of powder with the 1085-grain Brass Darwin.

About 4 grains added powder makes up for the 2" shorter barrel, at the cost of only about 1500 psi added peak chamber pressure ... roughly speaking.

I found odd steel block with a square cornered
1.0" by 1.5" hole through it. It solves a big
machining problem for me in doing a 4bore.
And I happen to have some 1" by 1.5" steel.
The rest of machining I can do, and I have
the levers, hammer, trigger, etc. But the parts
and layout are not going to copy the Wickcliff.
To many problems with all the parts riding on the
breachblock and the crowded stubby extractor.
Will be my own design with hammer and
trigger behind breachblock. An extractor similiar
to Ruger and its shape a cross between WIN 1885
and a Farquarson.In pic you can see drawn outline
on the block of the shape it will have.ED

Wow, Ed!
That is ambitious!
Should be easily adaptable to 12GaFH.

Yes great for 12GA FH, 8ga, about any big case.
I have a rough model to work from and the
ambitious part is done, getting a good
hole for the breach block. I have rest
of action parts all ready from other sources
like Gunparts, etc. Ed

Ed- Youll be whitling on that Block for awhile. I suggest you rough it out, then heat treat it.-Rob

Ed,
What barrel thread will you use for the Hubel Falling Block?
Is that steel the usual chromoly 4140?

Ed- Save yourself alot of work and lay out the action profile you want and then have the block EDM cut to trhat profile. You could do it on a CNC mill but it would take quite awhile. Thats what old Al Story did with my Borchardt. I'd do a 1.5X 16 Thread for the barrel Tennon and use a 2" barrel like on my Borchardt.-Rob

quote:

have the block EDM cut to trhat profile

Absolutely! Might be a good idea to identify what, exactly that material is before expending the effort. 4340 VM HT blocks with material cert are dirt cheap. That slot could be EDM'd for $75.

Gotta admire Ed's Madmax approach to gettin' it done though...

Steel is like whatever alloy is used for
NEF SB2 actions and is about RC36-38 hardness.
Had a guy check it in comparison to NEF.
My barrel is 1 7/8 so I'm making thread
probably 1 5/8. Seems very tough. Figuring
hardness, the action has breach thrust
rating of 50,000 lbs. A 4bore case at 30k psi
will gave a thrust about 18,000 lbs and get you
way over 20,000 ft lb loads.

Only probem with EDM work is, here I'd have to
spend hundreds going 200 miles, couple days
stay, plus EDM charge.And hole is already
done, a perfect fit for steel bar I had here.
The rest is easy on my lathe and vertical
mill now.I have pivot lever , linkage, and breach block
done already in 3 weeks. Small parts, springs, pins,
already done from Gunparts and my parts..Ed

This is probably not a madmax preferred scenario. I took my time and got everything right. Agreed, Ed you really need to know what type of steel your starting with. DCM will give you a complete understanding for under $100. wELL WORTH IT. Yup EDM is not that expensive and the results are well worth the cost. You have one chance to screw it up. Dont take it!-rob

UPS roundtrip to you from any of the HUNDREDS of EDM shops in So-Cal or Vegas is about $20. A lot cheaper than nuking yourself Ed! You're worth more to us alive Boss ...

Ed take another look.

4-Bore smokeless loads can easily be 40,000 PSI.

4-Bore thrust area = .786" +/-

40,000 x .786 = 31,140 PSI.

Assuming 120,000 PSI material and SF of 2 - you'll need .519 SI of material section in any area which sees thrust.

Note - theoretically, you only need a total of .519". IF you can spread the force precisely over all the stressed areas. That's a fools game when messing with big guns. Our 2-Bore action has a SF approaching 30.

Formula I use is cross section of the base times pressure,
times 2/3, The 2/3 is to take into account the thrust
that the cases take and the difference between outside
and inside of case.It has worked for me for many years.
But loading 40k loads, 30k ft lbs, even I can't shoot them from
shoulder in my old age.

Case base is 1.093, base area is .95 sq in. times 40,000 psi
times 2/3 is 25,000 lbs of thrust. 30,000 psi is 18,750 lbs thrust.
The steel is 90,000 lbs tensile strength. cross section of
two sides is 1.25 sq in x 90k tensile is 112,000 lbs divided by two
for shock load(most designers use two)
gives thrust rating of 56,000 lbs.Ed

Hey it's your gun and your cabeza amigo ...!!

My math is real close,I just make it simple.
Here is complicated drawn ou way......like
friction on the case holding thrust is the psi
times the area, times co-efficient of friction.
Perfect friction, the figure is .045, I use .030. That
times 30,000 psi times about 12 sq inches of case sides
gives 10800 lbs of friction.Cross section of the
sides of the brass case that has to hold thrust
is .180 sg in. Times the tensile strength of good brass
at 50k gives 8,500 divided by two for shock loads
gives 4250 lb thrust it can hold, and friction is higher
than that, so 4250 lbs of thrust is held by the case.
That along with inside/outside section areas
accounts for the 1/3 less in the formula.
You take the wall area of .18 from .95 base gives .77 sq in
times 30,000 psi gives 23100 lbs of thrust minus what case
holds, 4250 gives 18800. Simple formula was the same.

As for action strength I figured area section of
the steel sides less than what it really is.Ed

Ed:
You lost me after -

quote:

Here is complicated drawn out way

All I can say matey is "Just dont blow your self up!" Because its gonna be damn hard trying to get a 21Gun 12GaFH Salute, we simply dont have enough of them yet! - OK!!

PS : Ok Robs new toy sorta counts as 2, but the big wuss wont fire both barrels at the same time!!

Carry on.

The action needs to be proofed anyway and ED is way smart enough to do that. If its gonna blow it will be on the Proof.I always push my guns hard on Proof so that an accident never hapopens. Thats just playing it smart.-rob

Back to the mundane 12GaFH load development, temporarily:

As Ed said, the RL-17 is indeed reliably set off by a plain ol' CCI-209 shotgun primer.

However the best I could do was 25 yard velocity of 1483 fps, equivalent to 1593 fps MV (assuming .150 BC)
with
175.2 grains of RL-17
1085-grain Nohbozo brass Darwin
and filler consisting of:
one nitro card of 0.070" thickness over the powder
one 1/2" thick fiber wad
and 5 grains of Dacron right under the slug
COL 4.180"
with 3.5" RMC brass
and CCI-209 primer

All the RL-17 shots fired, but left a lot of unburnt powder in the barrel.
This was about 200 fps slower than expected.

Recoil was noticeably less with the RL-17 loads than with H50BMG producing equivalent velocities,
as it should be,
since those H50BMG loads burn about 60 grains more powder, including the 15 grains of Blue Dot starter.

And the H50BMG with Blue Dot/CCI-209 burns more completely than the RL-17 with CCI-209 alone.

It must be the weak CCI-209 primer,
which is more than sufficient with Blue Dot starter,
probably even better than the CCI-35 primer.

Maybe RL-17 would be the perfect powder with a CCI-35 primer. Top velocity for least recoil ... if it gets burnt more completely.

Two questions for the 12GaFH Council:

1. I have a mind to try 15 grains of Blue Dot starter and CCI-209 with the RL-17.
What does the 12GaFH Council think of this?

2. I have been assuming a BC of .150 for the Brass Darwin beer kegs.
I need a good BC estimate to back into the MV, when chronographing at 25 yards.
Can The Council give me a BC estimate for the 1085-grain Brass Darwin?

Using heavier 1/8" card or good plastic seal and
all wads to the slug, no dacron.
From my recent experiments you might get best
and what you expect -BPI column - 2 BPGS seals
and a Flexseal and their .In picture.
Shown under their sabot. Those 4 pieces in
Brett's and my testing seem to be magic.

10gr Blue dot max with RE 15,17, 19.

If you use Blue dot starter only use 10 grains
on any powders faster than Alliant RE22, IMR 4831,
VitaVouri VV165, Hodgdon H1000.Ed