Originally Posted by timmyatnop
Wow that looks like a great piece of equipment,I think iam gona have to invest in one when i get my other want's paid for. Jerry i read that you shoot a 300 rum. I purchased one last year and 200 rounds later have it shooting a good group, but my es is 33 fps and thats after i through out a shot that was 100 fps different then the other nine shots, Ive annealed all the brass measured powder so they were all 95 grs. rotumbo. I guess the thing i havent done the best is sort my brass by weight,mabey thats my problim,Oh one other thing i purchased a barret bors system and put in my bc off my box of burger bullets and its dead on at 100 y,but when i have my bors turned to 600 yard my group is a foot high and a couple of inches to the right,Sorry if ive got off the subject of annealing but thought you might have some expert advice for me ,I use rcbs neck dies mabey a collet die would work better. I read your artices on brass and bullet prep and am trying to fallow them closely,oh yea i use rem brass,fed 215 primers. Iam just trying to perfect this gun so that its the only one i use.Any advice would be great .
Big one is the actual weight of the powder charge. I have found that even in a RUM sized case, a variation of 0.2gr can have an affect on vertical stringing.
I gave up tuning over a chronie years ago as the error in the average chronie is equal to or larger then the speeds we are trying to monitor.
There is an article I have written about load tuning. The goal is to test at 200 to 300yds. By adjusting the powder charges in very small increments, you can dial out vertical in a well shooting rifle. The groups will look oval like a football on its side.
The accuracy will still be within the norm you expect from the rifle but there will be little to no vertical AND that is what we need for LR success.
Measure case volume after fireforming AND neck sizing. Forget about weighing the brass. There will be significant weight differences but the volume is likely spot on.
Runout is another easy thing to check. Long VLD bullets do like being launched wonky. I strive for 2 thou.
Match primers can help too.
So test at further distances. Watch the rests and shooting set up you use to ensure they are stable and repeatable. A good high mag scope and a clear target will also be a great aid.
As I mentioned in my article on scope set up. Don't trust what a ballistics program spits out or the assumption of BDC devices. Real world testing is the only way to know what your gear will do. Yes, there is error in every part of the optics/rifle system but as long as they are consistent and repeatable, we can adjust for it.
Hopefully, the BORS product you have can be reprogrammed for your real world come ups. I have yet to find a combo that was bang on. A few clicks either way but never dead on. So I just tweak my drop chart and have at it.
Good luck on getting your rifle dialed in. But remember that peak accuracy in a RUM is under 1000rds.