I have a Dakota 76 in 330 Dakota. I have not turned out to be the reloader that I thought I would when I bought the rifle, and the Dakota ammo ain't cheap. I was just wondering if it is possible to rechamber to 338 RUM, so I could make use of factory ammo.
Doc

Don,

I'm having that exact conversion done now. E-mail me if you are interested in the details.

You're making me want to cry.
Is your trouble around load development, or just sitting at the bench to assemble rounds?
If it's a matter of gethering load data, have you tried contacting Dakota?
I bet they'd be happy to help you not lose their proprietary chambering.
Also, you're going to knock a cent or two off the resale value of a nice gun I imagine.

[No apologies for trying to talk you out of it!]

I'd be interested in the details, BTW.
The bolt face is bigger in the Dakota; how do they fix it?
I guess they'll also have to open the action rails, since the base of the RUM is bigger than the Dakota/Jeffery dimensions.
But I assume the Dakota action can handle a 3.6" cat'ritch no problem.

Bwana-be,
Really my main problem is the hour in Atlanta traffic I have to hack through to get to my range. Also, and most significantly, my range buddy has taken a little vacation to Afghanistan, and is mostly wearing green these days. Maybe when he gets back, I can get back into gear to work up these loads.
Don

You could try the UM brass in your Dakota bolt and see if it works o.k. I'll bet that the approx. .010 per side dif. in the rim dia. would not make any difference. Also, you should be able to check feeding as it is now. Check the dia. of a fired round, at the base, and compare it to an UM round. If the Dak. is less than .545 your new chamber shold be fine. I'm pretty sure that the U'mag case is enough longer than the Dak that you will be cutting a complete new neck in the chamber.

Sure, the RUM ammo is, what? 1/3 the price.
But how much did you spend on the gun?
Consider spending the $150 of rechamber/feed-fixing on a hundred pieces of brass, and throwing together some under-max loads for the range (size, prime, charge, seat 25 rounds in .5 hours easy) or use it to buy a used gun, a savage maybe (cheap), in 300 Win Mag.
Nobody knows for sure just how long these Ultras are going to be around. They're only a couple of years old, you know. I think I'd choose a proprietary cartridge over an out-of-production one over and over!
Someday, with your light 3200fps 165-grain, sub-MOA load dialed in, heading out west for some pronghorn hunting, you'll think back to how you almost cut into that thing, look up at the clear, blue sky, and smile.

... or just get it rechambered.
Then, in 10 years when you're tired of the pounding, I'll buy it for a song, and rebarrel that mutha to 450 Dakota!!