Do you recall any dope for that load? Running JBM on a Berger 185 @ 2700 it's still outperformed to 1000 in drop and drift by a Sierra 155 2156 @ 2950
I've yet to see a 155 SMK 2156 win the drift battle over a 185 Juggernaut in the real world..
I ran #s at JBM:
Berger 185 @ 2700:
1000 yards the drop is 346.1", drift is 81.9" and energy is 740 ft lbs.
Sierra 155 2156 @ 2950:
1000 yards the drop is 330.5", drift is 98.3" and energy is 521 ft lbs.
SMK 155 2156 wins drop but does not win drift or energy on target at 1K yards. SMK 155 2156 has 16.4" more drift than does the 185 Berger but the SMK is 15.6" flatter. I'll take improved wind drift, I can get pretty good ranges with LRFs. Wind conditions between me and 1K are a bit harder to get a good reading on.
Berger 185 is inside of 155 SMK at every distance.
Berger 185 (1831.6 fps @ 600 yds) has more velocity than the SMK 155 (1832.1 fps @ 600 yds) past 600 yards.
Berger 185 @ 1K yards has 1342 fps, SMK 155 @ 1K has 1231 fps.
Past 1200, not really a practical range for 308, the Berger 185 has less drop and drift than 155 SMK.
185 Berger is 1250 fps at just under 1100 yards, 155 SMK is 1250 fps just under 1000 yards.
If majority of the OPs shooting is 600 or less, I can see a possible advantage to 155s.
OP, short answer is the 185 Juggernaut is the knee of curve bullet you are looking for to improve performance of your 308, IMHO.
What chamber is in rifle?
What is OAL of Berger 185 to touch lands? Berger 185 doesn't mind jump either but more as a data point to know how much case capacity you'll have to work with.
What magazine system are you running, max OAL mag system will feed?
What is maximum length of loaded round that will pass through the magazine cutout in receiver?
Twist rate of barrel?
Barrel length?
Ballistic calculators are great but in real world where one has to deal with conditions, bigger bullets with higher BCs tend to win at distance. YMMV