RE: 12GA From Hell
 

How old this thread is, you would think that post was made in 1980.:D

RE: 12GA From Hell
 

Here is a simple outline of what we've done with
our project we call the 12GA From Hell.
Some folks have asked us to do this.
A. The idea for this and the name was by
Robgunbuilder on the AR forum. We figured out how
to make a long brass case, from BMG brass by
machining rims and the case to screw them on.
We ended up with case after mouth was expanded
that was 3.85" long, with a big BMG primer.
B. Rob put his in a big Borchardt falling block,
a gun that can take full BMG type pressures.
It had firing mechanision that fired primers ok.
Example top load is a 1000gr turned brass slug at
3100 plus fps, and a 7/8oz 12ga sabot at
4300 fps.
C. First of mine in a Savage 210 bolt shotgun with a
heavy rifled 31" barrel. My loads in this were kept
below 35,000 psi. Giving loads of 2700 fps with
a 730 gr hard lead slug, and 3900 with 3/4oz sabot.
Second gun was a NEF Ultra that I lengthened chamber
to take long case. Top loads are 600gr hard slug
at 2500 plus fps.Both Savage and NEF had to have
firing mechanisions beefed up to fire BMG primers.
D. We cut cases back to use in 3" chambers but
all guns have to have beefed up hammers, etc,
to fire the big BMG primers.The BMG primers
fired the slow rifle powders ROB and I
were using very well, no misfires.
So tried 3" RMC brass cases, regular plastic cases,
our cut back cases with primer bushings, all with
smaller regular rifle or shotgun primers,
that regular hammers or firing pins fire ok,
and found out that our slow rifle powder loads
wouldn't fire reliably with small primers.
E. Which lead to much more research. We found that
slow powders could be fired with a 10 gr of a
fast shotgun starter powder, under the slow powder,
using small primers. We also searched for rifle
or pistol powders slower than shotgun powders,
that would fire with small primers and no starter,
that didn't up peak pressure to fast as
we increased loads to increase velocity.
We found three- IMR 4759, VV-N110, and 7383 surplus.
These powders are easier to load for slugs without
the problems of fast shotgun powders pushing up
the peak pressures to quick, as you try to increase
loads to up the velocity. We use a minimum
thickness overpowder wad or other wads in the loads
under the slugs as needed. We had lab test 4759
loads with 600gr slug and pressures were little less
than the magnum REM Buckhammer factory loads, but
we got 400 fps more velocity. The Buckhammer
slug and locked on wad is about 600 gr.Both our tested
loads and Rem loads are 3" plastic.Our loads are for heavy
barreled guns only. IE; all slow powder loads whether
with starter powder or 4759,N110, 7383, heavy barrels,
as the pressure curve is higher down the barrel
and might split regular skinny shotgun barrels.
F. We plan on heavy barrels for testing 1887 Win
leverguns, for Mossberg 695 bolt guns, for
various heavy double shotguns, for various
O/U, for modern alloy guns, etc.We are helping to
design a big falling block for 12ga diameter cases
that is reasonably priced.. We plan on testing
other powders, for use with small primers. We
plan on setting up pressure testing barrel for
the long 3,85" case, to test the whole range
of slow powders and bullet weights, in the future.
We have found heatreated Dixie slugs that can
take super velocities, we found brass slugs with
relieved grooves that run same pressures as lead,
or copper jacketed, at same velocities.
This research and work is super great fun,
we are glad to share.We will get pictures soon of
the muzzle blast with long case, and pics
of penetration tests. Ed

RE: 12GA From Hell
 

Found another powder that works with small
primers in plastic and RMC cases. 600gr slug.
It is IMR 4227. Ignition perfect, same load
levels and velocities as 4759. My earlier
report of 4227 not working was in error
due to what looks like 4198 in a jug
hand labeled 4227 I got in big batch years ago.
Greg told me 4227 worked for him so I got new
jug, and saw the difference from jug I had.

So slower than shotgun, powders that ignite
properly; we have 4759, VV-110, 4227, 7383 surplus,
the latter a slow powder. Ed[/align]

RE: 12GA From Hell
 

Pressure tested 7383 with heavy powder load.
870 gr with 128 gr of 7383-- All that could
be put in REM plastic and keep length to what
would feed from magazine of a 3" gun,
after it was roll crimped with tool in drillpress.
1513 fps-- 14700 psi. That is a slug 50%
heavier than factory Buckhammer at little
faster speed and at little less pressure.
Ignition perfect, cases fall out.
Love that $3 a lb powder.Ed[/align]

RE: 12GA From Hell
 

Finally able to make the
longer barrel improvement on
the 1887 12ga levergun.......
Rifled and heavy and 31"
long. After many months finally got
a barrel.Ed

RE: 12GA From Hell
 

With NEF. Plastic cases, roll crimped slug
in drillpress. 82gr IMR 4227 1650 fps,
with 730gr, 78 gr 4227 with 800gr, 1600.
Expansion on cases show little more pressure
as full loads of 4759 and 600gr.
Ignition perfect with small primers.
Ejects cases fine. Burns clean.
Got a GEHA bolt 12ga to put a heavier
rifled barrel on to test. Ed[/align]

RE: 12GA From Hell
 

Tested 870 gr in NEF with our long
brass case with big primer.I have NEF
with extra hammer spring for big primer.
Got 2000 fps and still able to extract case.
Would do little more, extractor needs
to be wider and set up positive.
Used 260gr of WC-860 and MagPro.
Could use RL-22, Rl-25, Retumbo, etc.
That's 7700 ft lbs.. I get 600 gr slug to
2300 plus in NEF, long case. so you can go
light or heavy.Ed

RE: 12GA From Hell
 

can you guys make a semi auto?

RE: 12GA From Hell
 

We have to make one on a Barrett 50cal
Autoloading Action, but more money than
I got. And if Idid a 12ga size caliber in
autoloaderI'd use my 700HE
belted case, which has as much or more
power and stronger rim to feed and
eject better.Ed.

RE: 12GA From Hell
 

More testing with 4227. Greg got little over 1500 fps in
3" plastic with 870 gr slug using 74-75 gr of 4227.
I did the same. This compares to much lighter
REM Buckhammer slug with more speed. Almost all
the way through 5 ft bundle hardwood boards.
I have Mossy 695 as well as GEHA 12 gauge
to put heavy rifled barrels on. And my 87.
Will be checking Mossy 395
for a guy who wants to put on
a heavy barrel. Ed[/align]