underdog,
Try taking about 20 or so "fouling rounds" out to the range next time. Place a practice target down range and fire the fouling rounds at the practice target until the bullet strikes are no longer rising, but are now 'clustering " on the target. Keep track how many rounds it takes to get there so you can take that same amount ( or a few more just to be safe) and run them down the barrel on a practice target before doing ANY group shooting or chronograph work. You will get better feedback during testing if you do this. After you have found your seating depth AND velocity sweet spots THEN take your hunting rifle to the range and fire a 3 or 4 shot (how many as you wish) out of a cold, clean barrel at a target down range. Then finish you range session by shooting rounds at a practice target until the bullet strikes are no longer rising but clustering as described above. Take the rifle home and DO NOT CLEAN IT. Leave it sit in the garage or some place else of your choosing overnite. Take the rifle to the range in this condition and shoot another group from this cold fouled barrel. Compare this group to the cold clean group. Which ever one is the best that is what you set your scope to and take it to the field in that condition. Try the first part first o see if the vertical is reduced or eliminated with the load you have now and go from there. Let us know here or at [email protected] if you have any more questions and what you groups you get at your next range session.
Try 92-95 grains of RE-25 and 180 Nosler Accubond with Fed 215m primers. You should see very good results. I have worked many Remington 700s in 300 RUM and all have liked or really, really like this combination.
I just finished working a load for a friend's 300 RUM. Itloved this combination was able to shoot a 3 shot group at 0.375. Not bad for afactory Remington.
