Hmmm. Missing. It was either taken down by nefarious forces or I never put it up. Can't remember if I posted a smaller one or not. Point is you form your brass, either from raw, cylinder brass (as mine is) or from an existing cartridge, size it as per normal, fire it and then resize it again. This time, it's now as "factory original" as a genuine factory case because it's been fired in its own chamber and will be resized in dedicated dies. Don't you just love it? More fun than we can afford...

My mildcat uses the 375Ruger Basic case-- a cylinder case that's about 2.67 inches (approx 68 mm) long. I trim it down to 2.55 inches (65 mm), then slam it through FD1. I trim it again to 2.55 inches, then slam it through FD2. I have to trim to 2.490 inches (63.246 mm) before it goes into FD3, else I smash the shoulder and trash the case. Once out of FD3, I trim to 2.490 inches and run it through the resizing die. I trim again to 2.490 inches, then expand the mouth prior to turning the necks with my K & M turner. Once turned, I resize again, anneal, then final-trim to 2.490 inches and "reload" it for the first time ever. Forming and prepping the brass takes some time but once you've done it, it's done. After that, it's "reloading" just like any other metallic shell you shoot again and again.

The .30-06 Springsteen cartridge has a maximum length of 2.494 inches. The chamber in my rifle has a maximum length of 2.504 inches. I had Lee Precision make my trimmers to trim to 2.490 inches so I'd have trimmed cases longer than the 2.487 inches to which their retail trimmer trims them. To me, giving up that .007 inches was just too much, so I gave up .004 inches. Yes; not much. But at just $15 each, I went for it.

Per K & M neck-turning tools: I advise anyone who is looking at one to choose another brand. The adjustment is a real pain in the ash. Seems you have to hit it on two or three threads to have the cutter move in far enough without running out of thread for said cutter to actually reach the brass. I tried and tried to get the cutter in just the right place such that I could turn the knob just a few little marks on the body of the thing to get my cut. Difficult. I finally got it close enough, then just left it. I don't want to have to go through that again. If I had it to do over again, I'd buy one that cuts to .0005" or even to .001 inches, instead of to .0001 inches. But the things are hexpensive, so I'll keep it and deal with the frustration.

Capacity of my case is 76.8 grains o' water, to the bottom of the neck. I see no reason to use the volume to the mouth. Somewhere, way back in time, it was decided to put a bullet there, so makes no sense to me to measure that capacity in the neck. If you must, the total capacity is 86.5 grains o' water-- same as the 308 Norma Magnum. A 300 Win Mag is 87.2 grains, and a .30-06 SpringBreak is 62.3 grains. My case is dam-ned near exactly halfway between the two. I think it's 2.0 grains (2.7%) above halfway. For the numbers, my case is approx 23% more than the .30-06 and about 9% less than the WinMag. It takes a low of 67 or so grains up to about 71 or 72 grains of magnum-type powders for most bullets of medium mass. I designed the long neck (same length as the SpringerSpaniel) to keep the heat and flame inside the case, saving the throat. That short neck and big powder charge on the WinMag costs about $1.00 a shot in costs to replace the barrel. Not what I need. The shoulder angle is the same as on the .30-06 Springfield, at 17.50 degrees. I chose that angle because we fired off gazillions of them in WW II. I figgered it was a good bet that my round would feed really well, using such a battle-tested angle. And it does. The 375Ruger Basic has no useless belt. 'Nuff said 'bout that.

Load development is an on-going process as of this time. I do not have any loads yet chiseled into stone. One I do have that's a bit hot is 68 grains of H4831SC pushing a 180-grain MatchKing to 3000 fps. Verified with nine shots on my blue Chrony. I say a bit hot because the primer gets a bit flat around the edges and I get "piecrusting" where the pin kisses the primer. I have gone to RL-25 and H1000, both at 68-70 grains, and these problems diminish or even disappear...

Loads are estimated by taking the volume of my case (76.8 grains) and dividing by the volume of a 300RUM case (105.5 grains to bottom of neck) or a 300WinMag case (87.2 grains to bottom of neck). This gives me a ratio. I then multiply that ratio by a listed load (using the same mass bullet and type of powder I’ll use) from another website upon which I am a member. Lastly, I multiply the quotient by an eight to ten per-cent reduction factor to get a starting load. If I get a good “shake” in the first loaded round, I load up more. If little or not enough shake to please my ears, I go lower still. Too much shake and I go higher, but not by much. My cartridge is a de novo design, meaning "of the new." It never existed in any form before I created it. No reloading data for it exists. I’m doin’ it all myself…

I wouldn't think a 300 Win Mag would be shot enough by a "average" user to notice barrel wear. The only calibers I've heard of that really eat barrels are the 264 Win Mag and the 220 Swift. If I wanted more .30 juice than my '06 gives, I'd get the time-proven 300 Win. However, I do realize that the fun of wildcatting is in making something unique. Sounds like your 300 mag will be pretty efficient and powerful.

broom_jm likes it. We've discussed it at length.

Powerful? The one load I have (the too-hot one) pushes out very nearly 3600 pounds-feet of energy. 3587 pounds-feet, or something like that. Is that a lot for a .30-caliber round? I don't know...

My round has also proved itself to be quite accurate. Problem I have is that the Hart barrel puts 'em into the same hole so badly that the bullet tears away the paper and I can't see the centers of the holes so I can use the OnTarget software to determine group size. I shoot five rounds from 100 yards, and I get a ragged hole about the size of a nickel. Can't discern the centers because there's no paper there. I have not shot at greater distances where this tearing-away of the paper should be a lesser problem because load development is ongoing, I worked too much, was too tired to saddle-up and get out there and now it's Winter, so 95% of shootin' is on hold until it begins to warm up in later February. But by then, who knows if we'll even be able to own a gun?

1. The simple reason everyone uses the case mouth to determine capacity in H2O, is the pesky meniscus. You have to get it flat across the case mouth.

1. The reason that there is no real difference between the 308 Norma, and the 300 Win. in a std. length action, is simply from the same bullets being seated deeper into the Win Mag case.

You have made a rimless, beltless, 308 Norma Magnum. It's a 300 magnum, regardless of your mildcat label. It will shoot as hard, and kick as hard as any in this class. The sharper shoulders of the Winnie Mag were to hold more of the powder in the case, than the 300 H&H did.

Your neck and shoulders should be only a smidge less accurate than the 300 H&H's. (16deg. vs. 17:30deg.), and that old round is deadly accurate, with a good custom chamber. So, from my viewpoint, you have the gentle shoulder angle of the 300 H&H, and the neck of the 308 Norma. It should do exactly what you wanted. But a mildcat, it's not. The real mildcat in the thirty cal. family, seems to me to be the new 300 RCM. This actually splits the difference between the 06, and the 300WSM.

I bet your wildcat will throw a 200 gr. + bullet better than the 300 WSM will, from the short actions. Better, means a better neck release, from a longer neck, than either the 300 Win. Mag, or the 300 WSM.

Your case diameter for the first inch from the primer is half way between the WSM and the Winnie Mag. You do pick up most of the efficiency of the WSM, as the Ruger parent is more efficient, inside, than the rebated RUM family of cartridges.

But you and I would be splitting hairs, to compare slightly larger diameter powder columns, to the Ruger's thinner case heads. I feel the die is cast in the first 1.5 inches from the primer. If I'm right, you have a full blown magnum, wrapped in a good set of design parameters.

But if you look at a 308 Norma Magnum cartridge case, you will see that it squishes down at the shoulders. They sacrificed a bit of capacity for this smaller diameter. Between yours and the Norma, I would go with the old 308 Magnum, if I was building a featherweight Alpine rifle, on a std. length action. Your round may be a bit too large of a hole in the barrel, just ahead of the receiver ring, and the Winnie Mag's shoulders, may be too deep of a hole into that same, rapidly tapering, barrel profile.

Those extra efficiencies of your large diameter cases may slap you around a bit more on the back end, but there are too many other values to consider. There have been wildcatted 300 x 7mm Weatherbys, and I bet your "Mildcat", will outperform them. I'm betting that your larger diameter powder column of the Ruger parent will trump the venturified shoulders of the std. length Weatherbys.

Furthermore, if you trimmed back a 300 RUM F.L. die to size a 2.5 inch case, I'm betting you will be very close to your mildcat, if the neck and shoulders stay the same. I did a full length test 300 and 338 RUM comparison using my custom dies to "neck size" the longer Remington cases, against ones made from full length 375 Ruger Basic Brass, and only got about three grains of H2O difference. Squeezing down the sides of the Ruger Basics, will make them grow to the full length of the RUM's, in my custom Boer 8 mag die set.

All I can say is that the Ruger is more volumetrically efficient than the RUM, on the inside. So you have a tiger by the tail, with your misnamed Mildcat. Your larger and more compact powder chamber, should outperform the Winnie Mag's., and I think you wouldn't gain much by using the larger, rebated RUM case at the standard 2.5 inch length. Except for your gentler shoulder angle, you have a 30 Newton, by another name.

Many thanks for that reply, carboss. Lengthy. Informative. Good reading.

I get my water capacities by cutting off the neck (with a hacksaw and a cordless drill as the case spins in the clamper-thingy made by Lee) and measuring the volume of what's left. It's very easy to do and I get flat-flat menisci by striking the opening with the back edge of a paring knife, or some such straight, thin edge. Then I dry the drip-offs with a terrycloth towel to keep from adding mass that really ain't there. The cut-off case also gives me an unchanging volume with which I can measure appropriate powders for the present case volume and mass of bullet I want to use. I fill the case with Powder X, weigh, then reduce by at least ten-- and up to fifteen percent-- for a starting load. I also use the reduction ratio I mentioned above. That's easier because I do not have to fill a cut-off case with powder and risk tumpin' over the bottle when pouring it back. Never done that, but I'm all thumbs most of the time...

The neck in my rifle for the mildcat has .002" total clearance. I neck-turn to get a skosh under .003" total. I'm told .003" is what the best benchresters are running in their high-speed, low-drag smokepoles. I'm feelin' kind o' good that I'm sort of up there with those guys. Can't shoot like them, but that's their problem...

Just thinking: If someone really, really, really wanted to do it, they could take a 375Ruger Basic case, give it the 30 Newton length, slap on a 20-degree or 22-degree shoulder angle (to allow for complete cold-forming and easy chambering) and finish it up with a 1.25X-of-caliber neck and call it theirs. The round would consider many design questions and fit modern rifles. The Newton's head diameter is something like .525 inches. Small. Sloppy in .532-inch bolts. Maybe not, but I'm a believer that .007 inches is a mile in a rifle. Readily-available brass. Fun. Expensive fun, but when has that ever been a barrier to guys who love guns like we on this site?

Look at this guy! He's complaining about his rifle making one ragged hole groups! LOL!

Well, laugh if you want. I am not offended. But it is a problem for me. My 300WSM with its SAAMI chamber would consistently print half-inch groups from its Krieger barrel, and sometimes less if I managed to keep my cool come the fourth and fifth shot. I want to know how good this present rifle is shootin' so I can relate the info to all our friends herein, should they have any interest. But I can't determine its accuracy because there's no paper there to do it. So all I can say with a pure heart is that it shoots pretty well. We like numbers; we like figures about these pursuits. I can't generate any for they who might be interested...

I can understand your desire for empirical data and I'm not trying to bust you down. Just post a pic of the target to prove your point. Then others can see what you're talking about. You should be very proud of your success.

I usually just throw 'em away, they're so ragged. My shootin' buddy, JR, says I need to put a better backer behind the target itself. I have shot the box away behind the paper. His contention is most likely correct-- he's been shootin' for over 60 years. I do have just one group of four shots in the side of the box. They touch like a tight clover. I'd have to take a picture of it to show it, but it seems my pictures disappear. Several have. I think it was you, taco, whom wanted to see the .358-caliber dude on which I'm working. I posted the drawing. It stayed up for a while, now it's gone. Several others are also gone. Gremlins?

Maybe Hasse has been pulling them off for his own use, ha ha. I haven't tried to post pics on this site yet so maybe someone should chime in for a fix.

Maybe the price of bandwidth has gone up as the price of oil has gone down. Heard it's about 80 bucks a barrel these days. I remember in early November 2004, the fringe media was terrified (sky predicted to crash to Earth any day, now) that the price had "crossed the psychological barrier" of $70 a barrel. I think gas was around $2.00 a gallon or slightly less at that time. So why ain't it there or near it, now? Let's have it, Exxon, Shell, et cetera!!

Per my pictures, I have put up maybe half a dozen in the last month or so. All are MIA. Not sure right now, but I don't think anybody's pictures are showing. Site problem? nvshooter suffering from myopia? Only The Shadow knows...

Nv Shooter, Why destroy perfectly good cases, just to get volumes? Besides when you do this stunt, you are publishing out of kilter data, over the net. I try to use fired cases with fired primers in them to get uniform data. I do have a couple of putative cases which have to be measured with what comes out of my forming die set. But my custom dies are so close to my chamber dimensions, that it's almost a negligible difference. The online Powley powder computers use algorithms, which require capacities to be computed from the case mouths, and not their shoulder neck junctions.

Without beating it to death, a classic Newton chamber will accept the Ruger Basic case head, or the various belted H&H style case heads. The loaded Newton ammo was indeed smaller in diameter than modern gunsmithing would demand. The gentleman in Cody who does the Newtons, sent me his wildcat 416 Newton. It's made from the Ruger, is the full diameter, is 2.5 inches long, and has exactly the same volume as my 2.6 inch 416 wildcat's case. He uses Newton's 23 deg. shoulders and I use the 300 H&H's 16 degrees. If I do a smaller caliber, 30 mag., then I will have a rimless version of the 300 H&H, which will duplicate it's volume, neck length, and shoulder angle, and still fit into a standard length action.

This would almost be an exact duplicate of your 30 Mildcat's volume, and I would keep the panache of the old Holland's Super 30. Or at least, that of the top half, of their longer belted case. But there are already so many big 30's, that this one is way down my bucket list.

Besides, the O.P.'s questions on the 375 Taylor are already at a higher level, and aimed, pardon my pun, at harvesting larger game, in general. Over at Black Hole Weaponry, in Moses Lake, they dampened my interest in shooting elephants using 8mm Schulers. They said it worked fine, if you wanted to stand next to a dying elephant, and keep shooting and shooting. If a bear or enraged moose, surprised Hasse, I would want him to be carrying his 9.3 x 62, or a 375 Taylor. In real sub Arctic conditions, this should beat out either my 8mm Mag. or my 10.6 x 375 Ruger, except with those Speer 350 gr. Mag Tips, made expressly for Arctic hunting.

I only need to cut the neck from one to get my volumes. I have about 300 in total, of which almost 200 are still in the raw, that number to include about 40 that have been pushed through FD2 in preparation to be final-formed for the .358 Sierra Stomper once its FD3 and reloading set gets here. Got another hunnert raws on order; ain't come yet. Ever'body buyin' ever'thing in sight, these days...

I am also hard-pressed to understand how I am simultaneously perpetrating a "stunt" and publishing out-of-kilter data-- over the net, no less-- when my rifle is the one and only of its kind chambered for my mildcat on this entire planet and most likely in this entire galaxy. That is, assuming there is no parallel galaxy in which there might be a chance, albeit slim, that there is one therein. "And we thank you for your support..."

I took the picture and commenced to whuppin' on it with the OnTarget software. I measured the four shots. Average center-to-center size is .200 inches at 100 yards. I have tried twice to upload the picture to my picture-hosting site and get the BBCode to subsequently post the .jpeg here, but the connection keeps timing out. It does that sometimes. Very frustrating. I am on a wireless connection.

The best group this MRC action (long, magnum, lefthanded and stainless), custom-contour Hart barrel (stainless), 6-25X x 56mm Millett scope (the LRS-1 model) and delicate, little mildcat round has ever produced is .135 inches at 100 yards. It was shot using a Protektor 13B and my adjustable sandbag from my homemade, lefthanded shootin' table. Must have been gremlins that did that, too, because I was told by some prominent politician a while back than I can't do much of anything without his help. Must have been gremlins. Yep, gremlins...

Three times; timed out. Last effort at 0115 hrs PST, 12/28. Time for an IPA...

Measure capacity to the case mouth, then calculate remaining capacity with Quickload or any other similar program.

Since the majority of capacity data is to the mouth, I would go with that as a standard. Up to you.....

__________________
MikeG

I haven´t done annything with the pics actully. I was woundering aswell where they were

I'll use the cut-off case method. It works for me. I do not have to subtract the 8-9 grains of volume in the neck to get the theoretical volume of powder I can use. I also have the only rifle in all of creation that uses this formed case. Be hard to use my volume when prepping-up a load for a different cartridge. That is why I use my reduction formula-- because the examples have a greater volume than the case being charged.

I am under attack by the latest episode of my gout. Beyond painful. I can barely function. Would love to sit and chat, but it's just not possible. Catch you all later...

I was trying to make a joke but I guess it didn't come across that way-my bad. I was also hoping to draw you back into the conversation because me and NVShooter have been dominating your thread. Looks like I succeded on part of my intention.

I understood your joke, but where are the pics? :S. It´s okey, I don´t mind some discussion even if I´m the thread creator. It´s just interesting to read about what people think!