Two years ago I started having problems with my factory barreled 338 RUM model 700. Accuracy went down the drain and I was getting very frustrated. I went to my local smith and he looked in the bore of my barrel and found a crack in one of the lands, there was also an area in the barrel that was holding some copper. He recommended replacing the barrel. I had him blueprint the action and install a Douglas premium 4160 cm barrel finished at 27 3/8 and added a muzzle brake
Since the installation of this new barrel, I have fought this gun non stop. In the beginning, cleaning was a royal pain, as the barrel would copper foul very badly. I used the Tubbs final bore finish on the barrel and it seemed to help with the cleaning, but I still can't get the accuracy that I want. I have probably put over 250 rounds through this barrel trying to come up with a load that meets my needs, but I am still not happy. I have made several good kills on elk with the gun, one at 582 yards with 225 grain accubonds and the other at 539 with 250 grain partitions.
At this point, I have given up on the accubonds, the best group I can get is about 3 inches. Today I went out and shot 5 more loads and to say the least, I am not happy. The only bullets that seem to shoot out of this barrel right now are 250 gr partitions. 98 gr of H-1000 is producing about 2960 with standard deviation of around 15, 1.5 to 2" group. The other load that shows promise is 96 gr of reloader 25 in front of a 250 gr partition moly. This load had standard deviation in the single digits, but still only grouped at about 1.5" velocity was about 2930 average.
I have also shot some factory ammo through this barrel and it shoots about 2.5" at about 2800.
This rifle has a laminate stock that is bedded and floated, the scope is a sightron 4-16 (3rd sightron scope) with burris high rings and two piece bases.
The bullets the I shot today were shot with the bullets seated out to max length that would fit in the magazine, which is still about .090 off the lands. The OAL was 3.655. My prior loads actually shot better with the OAL at 3.580.
I had high hopes for sierra game king 250 bt behind 98 gr of H 1000, but these seemed to print to the same height, but strung out right to left about 4".
I am truly at wits end trying to make this gun shoot! When my original barrel was working right, 3" groups at 300 yards were the norm.
Is it possible to have a barrel that is this finicky with bullets or did I just get a poor barrel? The finish on the inside of the barrel looks excellent now and the throat shows no errosion.
Cases are all full length sized, primer pockets cleaned and cases trimmed.
I love the terminal performance of this cartridge, but I need better accuracy.
All opinions are welcome.