Looking for a 30 cal wildcat based off of the RUM

[Minesweeper3433]

So after some research I can make the RUM feed right from 338 lapua magazines. I would like to keep case taper the same but shorten the over all round just enough to not have to modify the lapua magazines. Basically move the shoulder back to the same point as on the 338 lapua and make the neck a bit longer to have more flexibility in seating depth with different bullets. I am sure someone has already done this or something close to it. Any info or links would be great.

 

[Wolfish247]

Uh, like the .300 Remington Ultra Magnum?

 

[Minesweeper3433]

Yes I want to take the RUM because I can use my action and bolt without any modifications but I would like a longer neck and push back the shoulder to that of the 338 lapua as then the RUM will feed from 338 lapua magazines. This will allow me to use the AICS magazines that they are making for their 338 lapua without modification to the magazine system. Basically making it so the RUM will feed from excisting platform and have greater flexability in seating bullets.

 

[IdahoCTD]

It doesn't give you the longer neck but necking down the .338RUM would be a quick date unless you wanted it even shorter.

 

[barnesuser28]

Why dont you just neck down a 338 Lapua case to 30 cal? Or 300 Norma? You are going to have to push the shoulder WAY back through multiple sizing dies.

 

[Minesweeper3433]

The reason I am trying to do this with the RUM instead of the lapua in a 30 cal is, one I have a 300winmag that is limping along now after about 600 rounds of fast hot firing at fun ranges and as it is a lighter countor I would like to save it for hunting use later. And two I would like to be able to shoot the heavier bullets as fast as I shoot my 178-190 class bullets out of the 300WM. I have the 300 winmag and would like to be able to have a magazine feed, and utilize the same bolt that I already have. If however there is another cartridge that I am completely missing then by all means please bring it in as my experience with wildcats stops at Ackley cartridges. I would much prefer less work if able to be done. However seeing as how the brass would be made once and used for as long as the primer pockets won't give up the ghost I am not too afraid of a bit extra work on the brass.

 

[Minesweeper3433]

So here is what I have so far.
I have to meet a base to the shoulder neck junction measurement of 2.397 according to the diagram listed on this site for the 338 lapua. This is the measurment that is most relevant to my project as it is what meets the rib inside of the magazine designed for the 338 lapua cartridge.

The 300RUM starts at 2.544 meaning I would have to push back the shoulder .147 if I didn't change the shoulder angle.

The 338 RUM starts this at 2.430 meaning I would have to to push back shoulder .033 assuming I didn't change shoulder angle. This also would need to be necked down.

The question is does one of the better manufacturers make brass for either of these parent cases and which one would be easier. If there is a better goal or aiming point for this speak up. If I am missing a cartridge that could be used as a parent case chime in. Any info is good info as my experience again is with reloading factory cartridges and a few AI cartridges.

 

[FilippoMo]

You could look into the 300 skaadi,while based on the 300 Norma it would fit your requirements.
Filippo
http://www.beyond556.com/bboard/showthread.php?5736-300-skadi-300-norma-magnum-improved

 

[Wolfish247]

Sounds like quite the project. Let me suggest you make a quick call to Dave Kiff at PT&G. 541-826-5808. Explain to him that you have the gun, but want to make a barrel swap to a wildcat cartridge based on the RUM casing, but that can feed out of 338 LM magazines. Give him details about which of the two bullets (you mentioned in the 178-190gr range?) you want to reload for, the brand of brass you'll be using and what the OAL you're figuring on and he'll be able to get the exact dimensions for the chamber and freebore you're wanting. With that he'll be able to come up with a reamer print that they can email you to look over. Do your homework! Look into lengths and measurements and see if that's what you want to go with. Then give him a call about any changes or further questions.

When you get that all squared away and they begin machining your tool, you want to make sure to give Hornady a call. 800-338-3220. Talk with their custom shop. They can make reloading dies (check into a set of competition Full Length Sizing, Neck Sizing, and Seating dies), and could probably make your life easier by making you some Hydraulic Case Forming dies too. It was a bit of a wait for mine but well worth it in the end.

Lastly, keep an eye out for a longer .30 cal barrel blank or one with a low round count in a smaller caliber (.308, 30-06, whatever) that you can get a smith to install and chamber for your rig. You might want to consider a brake or even a can for this monster. Keep us updated about what you decide to do!

 

[Minesweeper3433]

I have a 10 twist shcieder 29" and a pacnor 23" 10 twist all sitting waiting on my decision on how to use them. It will be suppressed.

I will wait on getting a reamer yet as I would like to see what else is out there that I can use to accomplish this. I know there has to be some other obscure cartridge out there that will fit.
From what I see Norma makes 300RUM brass however that would be the hardest to shorten down. If I could find a manufacturer that makes high quality 338RUM brass than I would go with that choice as it would be simpler and I would have quality.

 

[FURMAN]

If you want to keep the non Lapua bolt head and be shorter than the RUM you might take a look at a 30-375 Ruger.

 

[ThunderDownUnder]

Have a look at the 30-375 Ruger! Here is a link which has a lot of info and pictures on this case. http://www.longrangehunting.com/forums/f28/30-375-ruger-opinions-65446/

Ian

 

[glo]

This is what I have found when pushing the shoulder back on RUM brass. Its hard to do and requires several forming dies. RUM brass is incredibly thick. You will no doubt have to turn your necks and ream them. After fire forming then another firing you will start to have a donut. Again you will have to ream the neck.

If it were me, I would just neck the .338 LAPUA Mag down to .30 ca. Maybe do 40 degree shoulders to get some of the neck length back. I'm sure Dave Kiff at PT&G or Dave Manson at Manson Precession Reamers have an off the shelf .30/.338 LAPUA Mag reamer.

 

[LHSmith]

Neck down a .338 Ultra? I know someone who has done that.

 

[Minesweeper3433]

The more and more and more I look at this the more I am willing to go with a single shot action and run a standard 300 RUM. Can't find anyone that makes quality brass for the 375 ruger wildcat options and norma makes RUM brass that I could run but not in 338RUM which would require less changes. Then I could run the RUM with any seating depth I wanted in the single shot action.

What I am going to look at next is cost of brass dies and reamer for a custom wildcat compared to another action.