Mark,

with the Rum I would opt for the 26" just my thought mate.

After along wait I have finally managed to get a 338 RUM chambering reamer and can start building my new rifle. It will have a MRC stainless action , Lothar Walther barrel and a D'Arcy Echols McMillan stock.
The only question left is whether to go for a 24 or 26 inch barrel Will there be a significant loss of velocity with the shorter barrel as for the type of hunting here the shorter barrel is better.
Mark

On such a large-case cartridge I would strongly recomend a 26" barrel, or maybe 28".
Remember that you'll burn a lot of powder!

Mine has a 26" Shilen SM-barrel.

Mark, Remember that it's a lot cheaper to trim 2" off of a 26" barrel than to rebarrel a 24 to a 26". Try the 26" and shorten it as needed.......DJ

Any decent gunsmith you talk to about this will tell you that 26" is the minimum barrel length recommended for a utililizing a case of this size. If you want a shorter barrel I would rethink your choice of building a RUM of any cal..

Thanks for the input everyone, it looks like 26 inches will be the go.
Paticularly djpaintles point that it is easier to cut 2 inches off rather than try and add length.I have just delivered all the components to the gunsmith this morning. He expects it to take about 2 months , when it is finished I will [ with the help of my teenage sons ] post photos.
Mark

Mark , here is a copy of some of Hodgdon's data for the .338 RUM , taken in a 24 inch barrel . As you can see , they didn't have any trouble reaching factory level ballistics with that buffalo BBQing tube (grin) .Go for whatever length you think will feel and balance the best for you..........







250 GR. HDY SP (Starting Loads)

DIA. .338

COL: 3.580"



RETUMBO 95.0 2798 54,600 PSI



H1000 92.0 2756 52,400 PSI



H4831 84.0 2662 50,000 PSI



H4350 78.0 2698 55,700 PSI



250 GR. HDY SP (Maximum Loads)

DIA. .338

COL: 3.580"



RETUMBO 101.0 2964 64,500 PSI



H1000 98.0C 2923 62,400 PSI



H4831 90.0 2858 62,500 PSI



H4350 83.0 2820 63,000 PSI