Awesome, I was not well versed on those so I wasn't sure. I was thinking of doing a chamber cast from one of my 20's to see what was typical. I was already looking around at mountain moulds playing around with bullet shapes and weights. I wonder what I could load this to: I have an NEF rifle frame that is rated at Marlin (32,000 or 40,000; depending on the source) in the 45-70. Thrust will increase because of the increased head size, but I should have an increase over the standard 20 to call it a 20 Express....

Ok don't laugh, but....





I was looking around for a 12 gauge Ultra Slug Hunter to do some modern 12 bore experimentation and glanced at the 20-gauge version, which would fit my Handi-Rifle frame. I peeked at it for a moment and wondered if .62 would really be all that bad. I could do my experimenting and maybe let them fit a Buff Classic tube at the same time. I grabbed a hull and measured the base diameter. I knew that a 577-450 fit loosely in the chamber of my LT-20 so glancing at my Illustrated Reference of Cartridge Dimensions, I noticed that 600 Nitro Express is very close and is a 3� case. The 20-gauge Ultra Slug Hunter, I believe, is chambered for 3� shells, which is the open measurement of the hull meaning a 3� chamber. I am concerned about the sloppy fit of a tapered case in a straight chamber, but a bore-rider seated out would center the cartridge even though the sloppy fit would waste the brass. At 45 bucks per 10 (Horneber, Bertram is twice that) I would hate to not have a good fit to the chamber, but it is an intriguing idea. The idea of cast bullets with deep grease grooves and narrow bands (to allow it to crush down and fit the bore) in fire-formed brass might work. I wish I could find one with an un-cut chamber. I would like to get a look at the chamber and throat of one of these. Any thoughts?



Just for the record, I am uncertain of the pressures the 600 Nitro operates at and would not dream of loading anything into a Handi that it could not take. Nor do I dream of shooting elephants with this. I simply see this barrel and think it is deserving of something better than the current crop of 20 gauge loads.

Ross, has already played with that, it was in an article in Handloader, I believe, he was looking at doing it in one of the Rolling Block shotguns

The 600 NE has a case length of 2.8". The 600 NE IS a 20 Bore (20 gauge in American). The case is very similar to the shotgun case, albeit slightly longer. The peak pressure of the 600 NE is ~ 35000 psi (Jeffery load of 1850 fps)to 39000 psi (everyone elses load of 1950 fps).

Basically, the 600 NE IS the 20 gauge from Hell.

Dave- Would you mind looking up what issue of Handloader that was so I could order a back copy??

45LC-The 600 case is 3.00 in long, and it would be loose fit at the mouth, greatly shortening cases life with

excess expansion and resizing.You could buy a good fitting 20 ga turned brass case that would be good for 30-35,000 psi, in a bolt type heavy rifle,

which is twice as high as you could go in the break action

with a 20 ga head size,its head is exactly twice the the

area of the 45-70 that it is rated for at about 35,000 lbs.

So you could run 15-17000 psi with a 20 ga turned brass case,from say Rocky Mtn Cartridge.And that is a great increase over plastic shell loads of 10,000 psi.They would last for many loadings. You would run in a 20 ga half the pressures of the 45-70 to get the same bolt thrust.Ed.

Could a Ruger #1 action be rebarreled as a 20 or 12ga rifle? I'm thinking of trying to imitate the Gibbs that Seyfried highlighted in Rifle. I know that other manufacturers already make rifled single shot 20/12bore rifles. Are these bbls suitable for shooting roundballs and conicals or are they twisted too fast??

Ed,

The 600 NE is most definitely 2.8" long! The 577NE is a 3" case, perhaps you are confusing the two. Regarding thrust forces, I believe in reality, you will find that the thrust force of the 600 NE is considerably greater than two times that of a 45-70 when both cartridges are loaded to the same pressure.



With properly annealed cases I really doubt he would experience any major issues with using a 20 gauge shotgun chamber. It is, as you say, a sloppy fit, but then again so are most dangerous game rifle chabmers. They are sloppy for a reason, (same reason the military chambers are loose).

No the action isn't big enough to accept that large of a barrel shank.

The 600 came out at a shorter 2.8 in length, but was lengthened to 3 in, page 383 COTW, pages 423-425 Ken's

book.A 20 ga at case mouth is .650 while the 30 ga is

,775. And 20 ga chambers will have more clearance added also. That is way too much to work brass.And just as important a cobsideration is with too much clearance on the neck of case when loads are being developed there is good chance that gases can leak back through that clearance,

and dent and damage the cases.In fact the lower pressures I am suggesting may have that problem all the time with about .030 clearance.That is one reason I wouldn't make thin mouth brass for the thick mouth paper cased designed Tula 4 bore chamber....



And base of 20ga/600Ne is about twice as big as 45-70 so running half the pressures in a brass 20 ga case will have thrust the same.

IE , 45-70 at 35,000 psi gives similiar thrust as the

20ga/600NE at 17,000 , just to make sure it is clear.Ed.

Ed,

Here is a sketch of the 600 NE, yes I borrowed it. There may be some odd ball 3" variants out there, but the standard 600 NE Jeffery is 2.8" long, always has been and always will be!



COTW is full of mistakes, half-truths, old wives tales, and blantant BS.

Your overly simplistic approach to calculating thrust forces may someday get you in trouble, Ed. Believe me that the 600 NE will have more than twice the thrust of a 45-70, when both cartridges are loaded to the same pressure.

The first was a shorter transiton from black powder 20

ga. But the 3 inch length is ICI- Kynock- Birmingham Proof

House- CIP- standards.Look it up in Ken's.

AS for thrust a 45- 70 at a base area of .2 sg in with

35000 psi will have similiar bolt thust as a 600NE with

a base area of .39 at 17,000 psi.Twice as much base, and

half the pressure.I didn't say they were loaded the same psi, I said one with base twice as big, loaded to half the pressure, gives similiar thrust.Simple.Ed.



Read what we said, nowhere did I suggest 35k in the 20 ga

for his break action.

Pointer-They do #1s in 577NE. The 20 ga rim is .012 bigger,
and the 20 ga base is .030 bigger. It could be done with lower shotgun range of pressures.20 ga chamber, with
brass cases in a #1, sounds neat to me..Ed.

Thanks for the sobering info, I may go ahead with my 12 bore experiments instead, there seems to be a good selection of projectiles in that size although I may still do some stuff with the 20. Hamilton Bowen does .577 BPE conversions on the #1, though he has put a hold on more orders until her gets things sorted out with his barrel reboring contractor (who appears to be about to retire). I will definitely look into the turned brass for both. I guess the worse I could do is to get the 20 gauge barrel, and if I don't like what is will do in my action, have a machinist take a couple of inches off the breach along with the mounting points, and then have it rechambered and threaded to fit a larger bolt action.

45LC-Check out a Savage 210 Bolt when you can.With heavier 20ga/600NE or 577NE barrel in place of the thin 12 ga slug barrel they come with, you could run good pressures.I am doing a heavy barreled 12GA FH on one.I increased barrel diameter from 1.115 at breech to 1.500 in and diameter at muzzle from .920 to 1.39 in.There is a thread on here and
pictures you can check. Ed.

Thanks for that!!!!! I sorta had my heart set on a Greener SXS 12ga, but once I priced a couple that went into the dreams only file. This may be an affordable alternative with some mucho class.

Ed,

I�m really wavering on this one. There is a certain romance to a 12-bore that really draws me but I must say that doing the 20 would be more practical for me. If my experiments do not pan out, I could shoot conventional sabot (or heavier versions of such) slugs in a gauge I am already set up to shoot sabot slugs in (I have a Cation rifled choke tube for Mrs. Powell�s LT-20, heavy stuff would simply be loaded to 3� specs that would not chamber in the 2 � Remington) or I could have the barrel machined as you suggest. The bull barrel could be cut down and rechambered with no ill effect and could be fitted to the Savage action. I will likely get bored with the heavy 20 and want to make a 600 NE later on, anyway.

I should like to find out the twist rates for these barrels to make the final decision though I seem to remember the 20 having about 1 in 34 to 36, which should not be bad and could stabilize a 950 gr. projectile. If I follow my mind, I will save a bill and do the 20�but let us see what the twist is. I will call tomorrow and report what I find.

45Lc-One thing about the Savage 210, it is easy to change barrels and bolt heads for different calibers..Ed.

Ah, meaning that the only machine work would be on the barrel, yet another reason to stick with the 20. And reading your 4-bore posts (great stuff, but a little beyond my ambitions) I see that Rocky Mountain Cartridge could easily turn cases that would take advantage of the sock bore yet be thick enough to use standard 20 gauge components. I will definately do some business with them whether I go with the 12 or the 20.

This is sort of a letdown, twist on the 20 gauge is 1 in 28", it is the 12 that is 1 in 35". The design I was looking at from mountain mould is designed for 1 in 39, though I don't know what velocities we are looking at.

45LC- The 1-28 twist will work fine whether low or high velocity. 20 guage turned cases are $3.70 ea plus shipping

from Rocky Mtn...Me for a 20ga/600NE size bore , I would just buy a 600NE barrel from Bauska, in whatever twist

wanted, put it on the Sav 210, and change bolt head to fit,

open the port and action, etc. And being built for 600 it will be thicker and heavier barrel,Chamber for the 20 ga.It still will get hold pressures, for velocity close factory loaded 600NE.

Just think of it a 20 ga matching a 600NE, when you use

brass cases for heavy slugs, and still shoot shotshells in it also.Ed.

Would cast bullets used for the 600 Nitro work for a 20ga??? This bullet from beartoothbullets.com would surely add some bite to a 20ga.

45LCshooter, go back & look at the 12bore again! It's EASY to get brass 12ga shells to load, and there's a NEW slug available with a big lube groove and crimp groove so you can load it in your choice of plastic or brass shells. It's called DIXIE TERMINATOR. There's also a smoothbore version (PREDATOR) that comes out a little less weight.

This Terminator is truly a MONSTER 12BORE SLUG!

Detailed pressure data on the big Terminator Slug on this link: Dixie Slugs Terminator Slug Page

Dixie Terminator-.729"-740 gr-40 grs Alliant "Steel" powder-1350�/"-10,500 psi< !--color-->

Also available with dry MOLY Coating.

Midway had/has 12ga brass shells for about $14.00/box of 25. You can boost the load to pretty good velocity in a strong repeater action like a Remington 870, but if you want a side by side, the DeHaan SxS 12ga is a Greener Style Crossbolt gun for way under a grand... You could shoot smoothbore style slugs from one of these and game would never know the difference if you're close enough!

DeHaan Shotguns SxS Doubles & OU

pointer,
That is certainly an impressive one. I will get at least one to put on the shelf but I want to see how we do with the 830 grainers from Liberty shooting supplies... I will probably hollow-point them down to about 750gr and work up.

Gowge,
Too late! The frame has been sent back to NEF to have the 20 gauge barrel fitted. The 12 bore is what got me interested, Paradox bullets at that. I am content to see what can be done with the 20.

As the plan now goes I will do some shooting with modern sabot slugs to get a feel for what it is supposed to do once I get the barrel. I may tinker around with a few different bullets in relatively light loads in the plastic hulls while waiting for the brass (since these are custom cases, I want to give David Casey the chamber measurements he asked for) to give some low velocity test runs on the cast bullets. With the turned brass, I will bump up the loads. They will probably become very uncomfortable well before pressures are a problem. High speed sabots will also be tried. This will take some time but I am excited. The same discussion is also being held on the single shot forum.

Well, by the time you're ready to load some serious slugs, the team at Dixie Slugs should have the 20ga version of the Terminator ready to go! Let'em know if you're interested in loading it in the brass shells and they can decide on the crimp groove for the 20... You also have the option to load some big musket balls in plastic shells too. Baker wrote about using hardened ball loads in the smoothbores of the time in Ceylon. Have you read his book about shooting elephants with round ball & conical loads?

GOOD LUCK!