Is it possible to withstand the recoil of said round with say the case loaded to 90-95% capacity if you have a fishgill style muzzle-brake, and the gun weighed around 28.lbs?

Does anyone know just how much chamber pressure would be generated; and how fast a 1500gr slug would be traveling at out of a 30" barrel?



P.S. This is a serious question by the way

Loaded to 60k in an action that can take it, 1500 gr should do 2500 plus fps with full case,and about 2300 fps with 90%
fill.Recoil should be manageable with 30 lbs and good brake.
Not for leaning forward over bench but standing..Ed.

The 12 ga FH will kick like hell too, at the bullet weights and velocities that Mr. Hubel is quoting.



1500 gr @ 2500 fps in a 30# rifle will have a recoil velocity very close to a 11 pound 500 ASquare (no brake). It will also require an incredibly efficient muzzle brake to stop the rearward movement before you are knocked off the bench. I would not shoot this thing prone!



1500 gr at 2300 fps in a 30# rifle will have a recoil velocity in line with a 460 Weatherby mag (no brake). Same statements apply to this one as did the 2500 fps load.



A 50 BMG weighing in at 30# will have a recoil velocity of 9 - 10 fps (depending upon bullet weight). The 12 ga FH @ 30# is around 16.5 - 18 fps (ouch if shooting prone).



The 12 ga FH ain't a bench gun at 30#, and it ain't a hunting rifle at 30#.



So I ask the question, what the hell is it? I cannot comprehend a practical reason for such a rifle. If it weighed 50+ pounds you could target shoot with it i.e. benchrest. If it weighed 18 pounds you could 'hunt' with it, but of course you would most likely not escape unscathed firing that beast at 18 pounds since recoil velocity would be 27.5 fps (dial 9-1-1)!



Now the the recoil velocities I am referring to are those generated only by the mass of the bullet being accelerated to muzzle velocity. You will feel this velocity regardless of the muzzle brake. The muzzle brake's job is to arrest or slow down the rifle's rearward motion i.e. dissipate the bullets recoil energy, by gas impingement on the brake's surfaces. That is why a good brake will have holes, which are 90 degrees to the rifle's bore. The escaping case will impact these flat surfaces and impart momentum (countering the rifle's rearward momentum imparted to it by the bullet's acceleration down the bore) and decelerating the rifle's rearward motion. Enough techno mumbo jumbo.



I also question the effectiveness of a muzzle brake since they require HIGH muzzle pressures to be effective. Typically straight-walled cases with long barrels have LOW muzzle pressures. This translates, in simple english, to an ineffectual muzzle brake!



You 12ga FH shooters don't shoot that thing at max loads prone, I guarantee it will kick beau coupe harder than a like weighted 50 BMG!!



Scott

The loads I quoted are with ball powders which will have
a good round pressure curve and enough muzzle pressure to
make the brake work for maximum help.Even stick powders,
due to the volumne being used will have good pressure for the brake.In my wildcats I found ball powder for full loads
is the best, and at night it looks like a Abrams firing off
a round.As far as weight, if your going after something
mean(IE; that can eat you, or in another scenario a Reno
rent-a-car) 30 lbs isn't a problem to me.And I never shoot mine prone, and my bench is a tall adjustable contraption so i can stand for chrono work....Ed.

First- SCOTTS you are on "IGNORE" so I don't read your DRIBBLE! HAVE YOU NOTICED THAT? YOUR AN ASSWIPE SO WHY WOULD I CARE WHAT YOU HAVE TO SAY? I THINK WE HAVE ESTABLISHED QUITE CLEARLY THAT YOU ARE A ANT-GUN ,PETA PLANT, PURPOSELY attempting to disrupt this site! YOU HAVE FAILED HERE JUST LIKE IN REAL LIFE! STRIKE A CHORD SCOTTYPOO? YOU ARE DISMISSED ONCE AGAIN!
THE 12 GA FH at full power in a properly constructed RIFLE with a GOOD break will be no problem to shoot offhand or from a bench! You will know it has gone off, but IT will not hurt you!
I have fired weopons that churn up nearly as much horsepower and had friends do the same. You would be amazed at how little felt recoil there actually is.
Don't listen to the DRIBBLE of people who's only experience is make believe like SCOTTS. HIS knowledge of HIGH POWER RIFLES is how shall we say it IMAGINARY! MOSTLY THE SAD RESULTS OF OVER MEDICATION. IF HIS LIPS ARE MOVING HE"S LYING!
GOD I ENJOY the "IGNORE" function!-ROB

Robgunbuilder,

Please take heed of what I posted! I do not want to see anyone get hurt unintentionally. Even you big boy.


Ed,

I hope you do get high muzzle pressures, you are going to need them. Even so the recoil will be VERY stiff, much more severe than a 50 BMG rifle.

Scott

Ed,

Question about loads. I ran a simulation with these values.

Bullet weight - 1500 grains
Bullet length - 2.085"
Bullet material - Bronze
Barrel length - 36"

105% compressed charge - 240 gr of a ball powder
Predicted muzzle velocity - 2429 fps
Predicted Peak Average Chamber Pressure - 67790 psi

85% case fill charge - 190 gr of the same ball powder
Predicted muzzle velocity - 2017 fps
Predicted Peak Average Chamber Pressure - 55447 psi

With the 36" barrel the muzzle pressures were down considerably.

Just curious as to what you are using.

Scott

I am using 60 to 80 gr more ball powder.Cases hold over
300 gr with no compression.Length is no inhibiting factor,
with the Borchardt action that Rob and Fritz are getting or the oversize Martini-Greener I am going to use.By the formula 1500 gr should be 26-2700 fps at 55-58,000 psi.
When we, Rob and I rework BMG cases to an almost straight
case(Rob's 700BMG, My 700HE, Our 12GA FH),the volumne way
up and better yet there is a whole new chamber shape that allows the use of the best ball powders that are in the
high medium speed range, with more energy per grain that is
not used to fight inhibitors.Ed.

Ed,

This is what I have been working with. I took a 50 BMG and worked it over in the computer.

Case length - 4"
Case internal volume ~ 387 grains of water
Bullet is monometal bronze at 1500 grains length ~ 2.1"
COL - 5.1"
Barrel Length - 36"

Load #1 with this model:
102% compressed charge using a medium burn rate ball powder
287 grains.

Predicted muzzle velocity - 2500 fps
Predicted Peak Average Chamber Pressure - 66,847 psi

Load #2
82% compressed charge using same powder as Load #1 is 228 grains.

Predicted muzzle velocity - 2057 fps
Predicted Peak Average Chamber Pressure - 52,072 psi

The muzzle pressures are way down though, due to the long barrel. You are under 8% of chamber pressure with Load #1 and around 5% with Load #2. Too low for a muzzel brake to be very effective/efficient.

You would be much better off with a 29"- 31" barrel as the muzzle pressure picks back up nicely. You will loose ~ 150 to 300 fps though.

Just in case anyone is interested the thrust forces are:

Load #1 - 27,900 pounds
Load #2 - 21,735 pounds


Powder I have looked at are:

W748, H335, BLC2 - too fast and potentially dangerous!

H380 - Still too fast

W760 & H414 - Still a tad fast for this thing, but workable.

H870 - velocity drops off but I think I may be better than the alternatives. It has been discontinued though, hasn't it?


What powder are you looking at using Ed? No I am not picking a fight, I am only providing my meager expertise and observations. All of this is based upon simulation data, which may be off a bit here or there. None of us will know what this thing does until it is actually fired.

Still don't start off from the prone position. This thing will kick good even at 30 pounds, of that I am certain.

Scott

Your simulation doesn't show the volumne of water that

the cases actually have, 340 grains.Or the amount of ball powder they will hold, 320 gr compressed.Or the actual

accurate shape and length(3.8 long- .800 base- .764 neck

with .729 bullet)Why I don't know.This is a case nearly straight sided on the outside, and more important,a little

angled out on the inside from base to mouth, due to the thicknes of the brass at the base making inside a little smaller, inside at the base, compared to mouth.Why is this important. Well inspite of the bottleneck case being in great favor, the chamber I describe can get more power out

of the loads in same volumne of case, due to the powder used, not having the need for so much deterrents, and

combustion energy not used to push against a shoulder,

when that energy is put to better use against the base of the bullet.Said shape is perfect for ball powders. W-760, H414(these two perfect for 1350 gr max load, will work for 1500gr and after testting may be best for max also), H-870(Got some),Surplus WC-860,WC-872.The VV double base powders also.There is enough different ones that the max velocities can be gotten with about any wt bullet.My barrel will be 32 inches.And for moderate loads we can burn up lesser

amounts of all kinds of surplus powders an still have

15-17,000 ft lbs of energy.Ed.

Thanks for the info guy's, I have a couple more questions though.

#1 Mr. Hubel, how much would it cost for you to load and sell 12ga FH ammuniton to me using 1500gr jacketed RN?

#2 Mr. Rob, are you an actual FFL; if so how much would it cost for you to produce a rifle with a falling block action?

Ed,

I know that the case I used was impossible to make from a 50 BMG case, as it is TOO long! However, to keep the COL down to 5.1" I needed that length to get enough powder in the case to reach your desired 2500 fps, albiet still at excessively high pressure ~ 67,000 psi!

I am sorry to inform you that with a total case volume of only 340 gr you will not get 320 gr of any ball powder in the case with the bullet seated to any depth at all!

If you insist that you can I will spell it out. In order to achieve a case powder charge of 320 grains, in your case with a water capacity of only 340 gr, the bullet will be seated to only 0.160" depth in the case and this with a powder column compression of 10%!!! The bullets in question must be at least 1.7" long to achieve 1500 grains of weight, and yes this is a jacketed lead bullet. If you dropped one of those cartridges the bullet would undoubtedly fall out!

It is really quite simple, Ed, the 12 ga from Hell only has about 30 grains more case volume than a 50 BMG. So you will be lucky to get 260 or so grains of powder into it. You would be better off to use the Soviet DShK machine gun round, i.e. 12.7 X 108 if memory serves me right, than the BMG.

By the way, I caution you against compressing ball powders. It is a well understood no no. I have experienced the consequences first hand. Everything you have said in this thread points to a minimum 110% compressed ball powder charge. This will be problematic.

Glad to see you are taking my advise on powder and barrel lengths, though.

Hope you find the development of this project interesting, fun, and fulfilling. Be careful though, and keep it safe.

Scott

I put one of the 750 gr 12 ga bullets that Fritz made,
in with 320 grains of BLC-2 without much compression.And BLC-2 along with W-748, WC-852 fast and slow, H335, H380, will be the powders that will work with 750 up to a 1000 gr.In big straight cases, Ball has worked compressed, with no problems for me, for many hundreds of rounds.And that is the weight of bullet I will started load development and then increase weight on up to 1500 gr or more.The bullet was .4 inch in the case.When I need to compress powder,I have a shaker that clamps to the press when I seat bullets to settle powder, thus making compression easy.And firing it off with BMG primers is easy. I got 185 gr, compressed,
of W760, in my 510 wildcat(soon to be 550), for 12,000 ft
lbs, and it holds 205 gr of water.Now these loads are just for bragging rights, IE, for hunting, letting friends get kicked, and earn a little notoriety, the loads will be between these and the starting loads...After mant years,
making Two wildcats of the same design, we found what to do for the results we want,
with safety...Ed.

Mr Hubel- A man of your stature should noy reply to the likes of ScottS. He is a bullshit artist with no knowledge other than he probably ordered a copy of quickload after Robgunbuilder kicked his ass over his bullshit 405 loads. You should put him on ignore like everyone else does. He's an asshole and knows nothing about the 12GaFH other than he sishes he was smart enough to have thought of it like you did.

470--I didn't think of it , Rob did...And relying on
Quickload, doesn't match real life on the big hairy straight to near straight cases.IE, chambers about twice
the diameter of 30-06 and twice as long allows for powder to compress a bigger percentage, easier, and bullet base diameter 2 and a half times bigger allows for more powder effiency per grain so the QLoad stuff for regular cases
that are smaller, bottlenecked, short; just don't match
what the 12 GA FH, 700BMG IMP, 700HE, etc, will do.. Ed.

Mr Hubel- Thank you! I expect your correct. I have no experience with something like this and rely on you and Rob to get it right. Man what a coo; idea! Any chance any of you guys would ever sell one of these behemoths? Money is not a problem for me. I don't pretent to have the expertise though.
Please ignore the HCI plant ScottS. I posted the truth about him!

I only built a few cases for 12GA FH, as with my equipment it is slow,and spare time tied up making 700HE cases which
I can do much faster.Rob said Fritz454 will make cases.I
don't know if they want to make loaded ammo.Fritz makes bullets also.So if you get rifle you can reload as Rob, Fritz and I will have it tested so you know what to load.
The only way to afford shooting this size case a lot is to reload.The brass is strong so it can be reloaded dozens of times..Ed.

Thanks for the reply Mr. Hubel. Would you be willing to sell some of your .700 HE brass since it's less time consuming to produce; and what would be the $cost$ per case?

Yes I will have 700HE with a headstamp in a few weeks.
Now it won't work in 12GA FH chambers as it is
belted case instead of a rimmed case...There are others
wanting some for their collections also...ED.

That's great! Whats the cost per case; and what address do I send my money to?

Nishoba-5 to 6 bucks ea depending on numbers bought plus shipping.And it will be a few weeks. Hoping to be able to deliver by April.Email me for order and I will email address, and get your address.These are made from unfired bmg brass and I have a half hours time in each case.Ed.

The e-mail has bee sent sir!

I just have a few more questions if you don't mind Mr. Hubel:

I'm about to start reloading ammunition (or in the case of the .700 HE Load ammunition) for the first time. I was wondering if you could give me your opinion on what reloading dies, presses, bullet runout meter, ect. I will need for this particular round and more specifically what manufacturers you prefer.

Whats the heaviest bullet that can be used with this round and would still have a velocity of 2200fps or better?

What propellant would be ideal for heavier bullet's in this round?

At what depth should the bullet be seated?

Which primers do you recomend?

Nishoba--The cases use BMG primers.Seat bullets
half an inch.300 gr of 50BMG powder will get a 1000 gr
bullet to 2200 fps, for a light load.320 grains of a little faster ball powder
like H-870 will get a 1500 gr bullet to 2200 for a medium load.To reload an Ammomaster press is good.With a BMG shellholder.CH-4D can make dies. Don't order dies until we
get load testing done and chamber dimensions set.You are going to have to get a BMG size action, like a McBros bolt action or Borchardt falling block action.Over 2 grand each,
plus a barrel, stock and brake.Glad you are showing interest in our boomers.Ed.

Scott, look page 213 0f Cartridges Of The World,
Tenth Edition to see powder capacity of reworked BMGs, in
the upside down domain of Mike and friends.They probably think we are upside down here...Ed.

Forgot to ask; out of what length barrel would I be able to acheive 2200fps with the 1500gr in the medium load, 24-30"?



Lets say for now that in order to obtain the desired velocity of 2200fps it would require a 30" barrel; if the light load consist of:

300gr of propellant + 1000gr RNFMJ + 30" barrel = 2200fps



and a medium load consists of this:

320gr propellant + 1500gr RNFMJ + 30" barrel = 2200fps



Could it be assumed that this would be the proper equation for a heavy load?

340gr propellant + 2000gr RNFMJ + 30" barrel = 2200fps?





Who would I contact in these companies:



Bridger

GS

Woodleigh

and Hawk

to get these bullest made?



P.S. Don't worry Mr. Hubel, I won't reload until you've done the necessary testing and given the ok to do so. I am new to this great hobby, and if all goes well I wish to stay safely active in it for many years to come, so I'll take what advice I can from you pros.



Edited: To remove the question of who makes the bullets because I read the e-mail you sent me after I posted.

Ed,

Thank you for the reference, I own the 8th edition, if I recall correctly. I went ahead and reworked up the 12ga FH. I came up with this:

Case base OD - 0.782 in
Belt height (measured from case body) - 0.011"
Case length - 3.8"
Internal Case volume - 340.1 grains of water

So I guess I have an accurate analytical model now as compared to your actual volume measurements.

Density information:

Water - 252.7 grains / in^3

H870 - 238.6 grains / in^3 (obtained from Hodgdon)

H414 - 248 grains / in^3 (obtained from Hodgdon)

Seating bullet depth of 0.4" give the following load details:

H870 100% load density - 284.1 grains
H870 110% load density - 312.6 grains

H414 100% load density - 295.3 grains
H414 110% load density - 324.8 grains

Bullet designs

Monometal bronze:
Bullet weight - 1500 grains
OAL - 1.87"
Point geometry - 0.6" meplat with 20 included angle to shank
COL @ 0.4" bullet seating depth - 5.27"

Jacketed bullet (bronze jacket)
Bullet weight - 1503 grains
OAL - 1.595"
Point geometry - same as monometal bullet above
Shank design - 0.05" jacket thickness lead core 1.125" deep from base. Shank is 1.25" long.
COL @ 0.4" bullet seating depth - 4.995"

Ballistics at 110% compressed load of H414

Monometal bullet
Powder charge - 324.8 grains
Muzzle velocity - 2427 fps to 2500 fps
Peak Average Chamber Pressure - 62,371 psi to 71,727 psi

Jacketed bullet
Powder charge - 324.8 grains
Muzzle velocity - 2421 fps to 2494 fps
Peak Average Chamber Pressure - 61,987 psi to 71,409 psi

That is it. I still think you are pushing the envelope BIG time trying to hit 2500 fps with this cartridge. The velocity ranges and pressure ranges are not necessarily respective of each other. In other words, you may only get 2421 fps (jacketed bullet) with a pressure of 71,409 psi. The ranges exist to show the range of possibilities in the real world. The load density data is accurate, I am certain of that.

This entire project intrigues me though, ain't that obvious. Please let me know how it turns out.

Scott

Nishoba01- I will probably make Dies for the 12GaFH or have CH4D make them. I expect a set will run about $400.

The best press is probably a RCBS ammomaster with the .50 BMG kit. I plan to use CCI-35 or RWS primers. Now the primer depth is critical on these and different than on any other cartridges. the .50 BMG primer has to be seated deep enough to "arm" but not so deep as to crush the priming pellet.

A depth of approx..005 is about right! As far a attaining 2200fps goes, I think a 1200 gr bullet with a case full of H50BMG should come pretty close at pretty low pressures. I will start with that and then move to about 250 grs of Rl-25 and then to Rl-22 and Maybe H414 for max velocity. I expect to have the first one done by March! all loads will be based on .700RLG experience. I'll post them when done! By the way I'd start with a 30-32 inch barrel and cut it down as necessary. Use a Vias type break!

I also see ol ScottyPoo is still posting his dribble. I'm enjoying this enormously-Rob

Rob--Scott's understanding of big straight case ballistics is getting better, and I think a lot of others are learning a lot of new stuff also.When the testing gets done for the 600 OK and the 550 MAG as well as 12GA FH and

added to your info On the700 BMG IMP, and

later my 700HE then there will be a great amount of info

and a better, appreciation of big hairy cartridges, with simple straight designs and strong brass.Whether rimmed like

12GA FH, Belted like others or Rimless like your 700 BMG IMP..Ed.

Ed,

Yes I am! I must admit that, at first I was somewhat skeptical, but the more research I do the more I find myself in agreement with your assesments. The 550 Mag has intrigued me as a hunting rifle. I anxiously await the first report on it. If it works out as advertised I may have to move up from the .510 bore.

Scott

Now as far as registering this rifle, since it's bigger then .510 will it have to be registered as a Destructive Device; or does this fall under some exemption? Is there even a need to register it?

You won't have to register it, as it is a sporting cartridge
and rifle.Just a different style of 700 that already
exists as a sporting cartridge.Ed