300 WSM barrel length, twist and contour??

Aquatic_Robotic

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Minuteman
Mar 7, 2011
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East Texas
Re-barreling a hunting rifle in 300 WSM. I plan to shoot 175-190 gr bullets and want to get around 3000 fps. I am trying to keep the rigged rifle 12-13 pounds. It sits in a McMillan A3 Sporter stock with Stiller action and Badger DBM. Barrel will be threaded 5/8x24 and have a 30P-1 attached so I want to keep the barrel as short as possible but still get the velocity I need.

More than likely using Krieger barrel. What barrel twist rate, length and contour will get the results I am looking for?

I am thinking 1:10, finished at 24 inch with bull sporter contour or heavy bull sporter contour with fluting.

I have not loaded for the 300WSM in the past, but I am now set up to reload for it when the rifle is complete.

Any ideas or thoughts would be appreciated.
 
I shoot a 300wsm. Mine is a simple stock hunting rifle. I load 150 grain Hornady SST's at about 3250 fps. When I loaded 180 SST's, I was getting a little over 3000. It's a Browning A-bolt with a 24" sporter barrel 1:9 twist I believe. The 150's were just a touch more accurate than the 180's and 165's. Good luck with it.
 
1/10 would be my choice, it will do the 200-210s if you like as well. 24" would be a handy length, you shouldn't have any problem getting the 175s at or above 3K fps, but you will need to push the 190-200s pretty hard but they will get there with a fast barrel and the right powder. The Sendero contour is good for 30 cal tubes, you can shave weight with fluting as you mentioned. One thing to think about, you are nearly gaining 1" of barrel length with a 300 WSM over a 300WM when you consider the chamber length of the 300WM, just a thought.
 
1 in 10 for 24" with 190's and less; 1 in 9 if you are going to shoot 220's, which are a waste of a good shoulder. Unless you are hunting the largest NA game, and there is a guy that did a very long write-up on the 300 mag, non WSM, that talks in detail about taking game with it, I wouldn't push the gun to 3000 with 190s. The barrels don't last long until they start to open-up and I've had better accuracy, your mileage will differ, staying around 2650 with 70gr H1000. Yes, this is a light load and I use magnum primers but I've been getting single digit STDEV and tight spreads. At 2650, the 190 is hitting at 2,963ft/lbs. You pickup 800 ft/lbs by pushing them to 3,000 at the expense of the barrel, heavier recoil that some would recommend crimping if you feed from the mag, and in my experience, accuracy. If you read that guy's dissertation on taking game with the 300 he talks about 'spectacular kills' with large game. 150 HPs at 3000 or so do a pretty big number on most heavy body game as it is.
 
I am rebuilding my 700 in 300 WSM and replacing the existing barrel with a 24" Brux #4 fluted with a 1:10 twist. Basically the only thing I am keeping is the action. The rifle is used for hunting and will be mounted in a McMillan stock and fitted with a Jewell trigger. Will be installing a brake since it makes the rifle much more pleasant to shoot. I have shot mostly 155 & 168 Berger VLD's through the existing rifle with very good results and will probably stay with those weights.