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300 Winchester Magum Wildcat

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I have a 721 Remington 300 H&H, at one time I thought about rechamberin it to 300 Winchester Magnum and was told since I had the long action, and rechambering the Barrel would require setting back the Barrel to much making the metal to thin around the camber. If I had to do this project a alternative was to rechamber it to 300 winchester magnum, then go in with a 30/06 neck reamer and lengthen the 300 winchester with a 06 neck.. I was also told that while the brass was a wildcat, in a pinch, I could use standard 300 winchester rounds

Can anyone share info about this ..
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I have one an improved version of the 300 win mag now that I have proven all the project notes are on my site venompublishing dot net.... I am getting a 333fps increase using a 200 grain Barnes bullet over the parent 300 Wincehster magnum... I am calling mine the 300 Venom Magnum Sniper, and it is ready to allow others to convert their 300 win mags if anyone is interested they can email me, and we can talk... intersesting idea... I have designed several wildcats using the Ruger cases... I am hoping to get one going soon.

I got acouple questions and don't take this wrong. I read your article and looked at some of the loading data toward the end of your article from April 5th thru April 18th you list everything but amount of powder used.
What is the volume

Hello NVShooter,
What is the volume of your wildcat 30-375 Ruger case? I like the .400" long neck, but it must down grade the orig. Ruger case's volume.
I got acouple questions and don't take this wrong. I read your article and looked at some of the loading data toward the end of your article from April 5th thru April 18th you list everything but amount of powder used.
Yes.. actually in some I only put the velocity comparison.... I have been getting a great deal of questions on this cartridge, and I am a little worried that someone would have the idea of trying to load the parent with similar charges. I am at the point now that I may allow the reamer to be used to do a couple of more rifles, and I am wanting to control ammunition until I know how other rifles will test with the cartridge. Also please understand that these tests are to show a comparison to published data... I ahve done very little work with seating depth, and other changes to see how fast I can get it to fly.
Case volume

Hello NVShooter,
What is the volume of your wildcat 30-375 Ruger case? I like the .400" long neck, but it must down grade the original Ruger case's volume.
Been a whole lotta redesign on the wildcat in the last two months or so. The entire thrust of this painfully expensive exercise is to generate a round that will FEED reliably in my long-action magnum rifle. I thought and thought. I scratched my chin three whole times. I was emotionally and spiritually exhausted. In the end, I changed the neck length, neck diameter and shoulder angle to that of the venerable 30-06 Springsteen. I figgered the 30-06 is the best-feeding long-action shell ever. How many millions were fired in WWII? Got a winner, there. So the shoulder height is now 1.834 inches from the head and the body diameter at that point is .510 inches. I cut a case to 1.834 inches (1.838 was as close as I could get with a hacksaw and file) and found it measured 68.2 grains of RL-22. The bottleneck will hold another 4.5 to 5.0 grains, so we are at 300WinMag capacities (I think) in the 30-06 envelope.

Ben Syring at Hornady is designing the three forming dies and two-die reloading set. He says I will not need to fireform. The resizing die is the last step in forming the cartridges. I asked if he could do this because I do not want to blast pistol powder down the bore of my new barrel. The dies went to order in late May 2011. Delivery is predicted for late September. Cost for all is $401.

Steve Satern is making the barrel. It will be 416R stainless, five lands and grooves, .298 minor bore and .308 major bore, left-handed riflings, nine flutes, 5.50-inch breech cylinder length x 1.25 inches in diameter, 29 inches long (excluding the contoured-in Shrewd muzzle brake) tapering to about .960 at the muzzle and 1:10 rate. I'm guessing six bills. $400 already sent as a deposit. I expect the barrel in July. Krieger said what I wanted was impossible. Satern said "No problem."

The reamer, GO and NOGO gauges are being made by Dave Manson. I am also having a pilot for barrels with a .300 minor bore shipped with the reamer in the slender event that anybody else might ever want to chamber any 30-06 bolt action in my wildcat. Cost for the reamer, two pilots and shippin' is $310. I expect delivery of these in July.

Machining will be done by the uncle of a friend's girlfriend. This gentleman has been at a lathe for fifty years. He has done aircraft and jet engine machining. He can do "two-tenths" work in his sleep. Says I can be there, watch, kibitz and assist. Says we can do it in his home shop in a few hours. My only question is how much to pay him. I'm thinking $25 an hour, or $100 cash if less than three hours.

I have named my cartridge the 300 Nevada Desert Magnum because I live in Nevada, I live five miles from the desert and it's a magnum. I can't wait to fire, resize and reload that first shell. I shall then just gaze upon a dream come to fruition...
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7mm wildcat...

Here's a 7mm thing I'm just tumbling over in my mind at this time. Parent case is the 300RUM cut off at the shoulder (gives a cylinder of 2.40 inches), but the 375Ruger basic could also be used. Length is the same as the 7x57 Mauser. The neck is long so the 168-grain and 180-grain Berger VLD bullets can be used. The bearing surface on these bullets is .462 for the 168-grainer and .541 for the 180-grainer. Overall length of a loaded cartridge using the Berger bullets will be right at three inches, give or take an RCH or two. Neck walls are presently designed to be .015 inches. If I ever do build this one, I'll use a Bighorn action, a Satern barrel and some sort of thumbhole stock that allows for the drop-in fitting of a Model 700 action. I like the Bighorn because it is available in a left-bolt with right-port configuration. I'm left-handed, so it works for me. Price is about a thousand bucks.

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First stuff is in...

Got the reamer and headspace gauges from Dave Manson on July 8. A beautiful piece of metalwork...
I have a 721 Remington 300 H&H, at one time I thought about rechamberin it to 300 Winchester Magnum and was told since I had the long action, and rechambering the Barrel would require setting back the Barrel to much making the metal to thin around the camber. If I had to do this project a alternative was to rechamber it to 300 winchester magnum, then go in with a 30/06 neck reamer and lengthen the 300 winchester with a 06 neck.. I was also told that while the brass was a wildcat, in a pinch, I could use standard 300 winchester rounds

Can anyone share info about this ..
Punch it 30-8mmmag/Super.
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