Any one out there intrested in a cartridge that throws a 250 grain slug faster then the .300 Ultra does a 180. Is flatter shooting shooting then the .338 Lapua, .338/378 Weatherby or any of the Ultra stuff. Has 5775 foot pounds at the muzzle and 3995 foot pounds at 300 yards and over 2400 at 600 yards? If so check out the .366 D.G.W. in the tenth eddition of Cartridges of the world. The D.G.W. is a neck down of the .416 Rigby and so far has racked up 34 one shot kills on both African and U.S. game. Some credit must be given to the .300 grain Swift bullets , they worked perfect even though I was pushing them about 300+ F.P.S. faster then designed for. The 300 grain bullets were at 2950 though I have had them a tad higher but I want to keep pressure down around Rigby levels. 286 grain at 3153fps and the 250 grain at 3260.

Your Friend
Jud

Quite some time ago I was pondering necking a .416 Rigby to .366 or .375. Nosler's 250 gr .490 bc .366" Ballistic Tips have slightly stirred my interest again. If Sierra ever comes out with a 330-350 gr .366" MatchKing I may have to build one on a Winchester action. That huge steep shouldered case has the appearance of serious potential, sort of like a .300 WSM on steroids, and the current brass is now designed for high pressure.

Sounds like quite a round there JUD.What kind of accuracy do you get from it?I saw one sitting up at your shop but don't know too much about the cartridge actually.Very impressive looking

woods

Tenth edition COTW is out? I'll have to look for it. All I have seen is the Ninth. Thanks for the headsup.

Where does one obtain formed brass?

If obtainable, how much does it cost?

Does the Rigby/.366 D.G.W. formed brass have more case volume then the 378 Weatherby?

I've been thinking about necking down a 378 Weatherby to a .366, shooting Nosler ballistic tips strictly for those long distance elk shot across canyons or open even clear cut which are sometimes 400+ yards. I would no longer have to be worry about tracking wounded elk all over the mountain side.

Btt.

Judson?

Sorry guys I did not forget about you. The .366 D.G.W. is a direct neck down of the Rigby case and has alittle less capasity then the .378 Weatherby. However the .366 bore diameter and bullet weights available are just about the optimum balance for efficiency with the Rigby case. With out a belt there is alittle more room in the mag and smoother feeding then if the Weatherby case was to be used.
Accuracy with the four DGW rifles, three are Ruger #1s and mine is based on an Enfield, shoot very will. with the proper loads one hole groups at 100 yards are the norm. The best 3 shot group with mine measures .487 extreem spread.
I think the rifle could do alittle better with a better shooter and some fine tuning on the load.
If you want to run the 286 grain Barnes Bullets you will have to go to a 1 in 12 twist, or only push them at around 2850 fps. instead of 3150 Shilen offers this twist. My rifle and two of the Rugers have 1 in 14 twist barrels This is standard twist for this caliber and handles all bullets well other then the 286 Barnes, these barrels came from The Montana Rifleman.
One of my customers got his loading dies from Hornady, I think they ran around $200. Unlike my dies from RCBS he does not need a forming die and a trim die. He is able to run the case into the sizing die, trim to length (the neck ends up a few thousands too long) then load the little guys up and go shooting.
You mentioned using a Mod. 70, I am not sure but I think you do not have enough shank diameter or action length with this action. If this is true check out the CZ550 or the Professional Hunter action soon to be out from the Montana Rifleman. I think it will be availably this fall. The CZ 550 is curently available. If you have more questions give me a call at 207-938-3595 or Email me at; theworkshop@tds.net

Sorry for the delay, your Friend,
Jud
P.S. I will try to post some pictures and loading info

Winchester once offered rifles on their CRF action in both .375 H&H and .416 Rigby.

That is somthing I did not know. I knew .375 was offered but not the Rigby.
The Enfield will work fine with either the .30-06 bolt opened up or the .303 bolt for .375 H&H size rounds. I rework my actions so they are simular to the 720 Remington but leaving extra metal on the rear bridge and such leaves weight which on a big rifle is not bad at all. One other thing about these actions, go to a coil spring ejector as this is their weak link. Got a customer so got to go, more later.

Eat your heart out .300 Ultra Mag and .338 Lapua etc. If you look at the ballistic cof and sectional density you will also see that this cartridge will out penertrate any sporting cartridge in the world acording to David G. Walker. From what I have seen and tested he is right. 3/4" steel plates with a Barnes bullet are not much of a problem, what a hole!!!!

Hot damn!

Where can I get forming and sizing dies?

Where can I get preformed brass?

What are the O.A.L or M.O.A.L ?

I am still waiting for the 10th edition of COTW that I ordered a few days ago.

What does "D.G.W" stand for? "Dangerous Goods Warning?"

Hornady will make dies for you and from what I have been told you do not need forming dies with the Hornady dies. My dies are R.C.B.S. and I have to use one forming die and a trim die before full length sizing. You can cheat and run the neck of the Rigby case into the bottom of a 30-30 die to start necking it down also. Right now there is no formed brass but we are trying very hard to get this cartridge picked up by one of the factories hopefully in a few years it will be a factory round.
The easiest way to get one of these rifles is to rebarrel a Ruger #1, I have done 4 of these and am going to try out the new CZ550 action and the action from Montana Rifleman. My rifle and the gun used for alot of the testing is based on the P-14, P17 Enfield.
If you need loading info contact me, be glad to share it with you

Your Friend
Jud

This looks like a FINE round, and much more useful than the 378 Weatherby. Nice work.

Just for the record, note that you may have some stiff competition from 375 RUMs seated out to 2.9 COL in the same length action. They are getting a 7.5% increase in usable case capacity and + 70 fps for 2930 fps with 300 gr Fail Safe bullets. SD is .305 vs your .320.

Similarly configured 338 RUMs get a 5% increase in usable capacity, pushing 225 gr Fail Safes and Nosler partitions +50 fps, for 3275 fps. SD is .281 vs your .266.

Looks like you have a round that will do BOTH from a single case...no small feat!!

I guess you guys never heard of the Lazzeroni 9.53 Saturn? a 300gr barnes X at over 3100fps? a real kick ass round, and just a little better than the .366 DGW, with bigger bore, and heavyier bullets faster.

Rock

One big addvantage you have with the .366 D.G.W. is that you are getting that 5600 to 5775 ME with a 24" barrel not 26"to 29". in addition to this the pressures are rather mild which means good case life. By the way if you run pressures in the 62000 range the 300s are going alittle over 3100fps and the 250 move at 3430fps, but here again this gets away from what this cartridge was designed for. Pressures that high in real hot weather,like Africa can have, can cause problems. Also case life is short and bullets tend to blow up instead of penitrating as they should.
If I caused some confusion I am sorry I should of put the muzzle energy figures with the rest of the ballistic info.

Your Friend
Jud

Question, where did those figures on the Remington Ultras come from? The Rigby case, even necked down has a bunch more case capasity. The balistics for the Ultra do not agree with the loading manuals or Remington?
Big Green says their .338 Ultra with a 250 grain bullet leaves their barrel at a velosity of 2860 FPS, a far cry from 3253. The .375 Ultra with a 300 grain slug goes a paultry 2760 FPS compaired to 2911 FPS. I also think Remington is using 26" barrels, compaired to 24". I do know that if you load the D.G.W. to the same pressures as the Ultras you will drive 250 grain slugs at over 3400 and the 300s at 3100 pluss FPS but this defeats the purpose of the cartridge

Judson -

The 338 and 375 RUM data are from the Nosler Reloading Guide 5th Edition, and both use 26 inch bbls. I have personally duplicated all the their 338 RUM loads and they are right on the money in my Rem 700 Stainless synthetic with 26 inch bbl. Absolutely no pressure problems.

I think the difference between manuals is that Nosler discovered R25 and is not afraid of pressues approaching 65,000 PSI. Certainly OK given the incredible strength of the RUM brass and the long chamber. R25 just hits the sweet spot with 225 and 250 grain bullets in the 26 inch tube. Here is their 338 RUM data:

250 gr Partition - 91.0 gr R25 and 2990 fps (page 424)

225 Partition - 98 grs R25 and 3227 fps (page 423)

Top Loads for the 338-378 were 3034 and 3220 fps, respectively with bigger doses of IMR 7828 and lower load densities.

Thier 375 RUM data gives these max velocity loads in a 26 inch bbl:

270 gr Fail Safe - 96 grs IMR 4350 and 3025 fps (page 469 top)

300 gr Fail Safe - 100 grs IMR 7828 and 2859 fps (page 469 bottom)

A friend at my local range is shooting the 375 RUM out of a rechambered CZ 550 Safari and seating them out to the full magazine length for a 50 to 70 fps velocity gain over the Nosler loads.

Top loads in the Nosler manual for the 378 Weatherby with 26 inch bbl with the same bullets are 3045 and 2893 fps with about 12% more powder.

I don't think there is too much majic here...the 375 Canadian factory loads are dead ringers for the Nosler data, and my computer says the Nosler RUM velocities are right where they should be for the case capacities and load densities. The same thing happens for the 300 RUM and 30-378 Weatherby in 26 inch bbls.

Lyman shows alot lower velosities loading manuels are funny that way. You are right about the powder. Remington uses Dupont powder and that means that the slowest they use is 7828 which is really a bit fast for these cartridges. I have not tried any of the Reloader powders, 22 or 25 in the .366 D.G.W. I have them but have not had the chance. By the way if you want to se that .30-378 come into its own run 180grain bullets or heaver and use a 29" barrel.

[ 07-10-2003, 16:08: Message edited by: Judson ]

Judson -

Good pick...my computer says it needs a 29.05 inch bbl.

For kicks, take usable case capacity in water grains and divide by bore diameter squared. When this number gets over 1000 it becomes very difficult to maintain cartridge efficiency if energy gains rely on increased velocity. If you increase bullet weight to get the energy and let velocity come down, you get impractical powder burn rates....too slow.

Shooting something fast that also has a high Sectional Density in an efficient manner with practical barrel lengths and barrel lifes belongs to the 750 to 950 range with the propellants we have available today, unless you want to use a sabot.

Jud it was great talking to you last night.

I look forward to working with you to build one of these guns. Keep me posted on any new developments please!!!!!!!!!!!!