Help with First time working up a load for 6.5 CM

[kykamo]

I just got a 6.5 Creedmoor Ruger predator and I haven't worked up a load before and am trying to figure out the best order of procedures. I'm looking to make more precision minded ammo than hunting "good enough" ammo.

Do I want to figure out the ideal seating depth first? And then find the best powder charge with that previous seating depth? Or the other way around?

And to find the seating depth, I figured I'd preload groups of four with a safe load (the minimum from the book???) starting with .005" off the lans and go .005 increments up till .03? And then find the smallest group of four and viola, that's my optimal seating depth?

And when finding the powder charge, do I have to start with the minimum, then go up by half grain at a time? One whole grain?

Thanks for your guys help

 

[bigedp51]

Powder charge first .020 off jam and then a seating depth test, read below.


Long range load development at 100 yards.
Erik Cortina, Team Lapua USA
http://forum.accurateshooter.com/threads/long-range-load-development-at-100-yards.3814361/

Some of you have asked for more detailed instructions on how I do this. Here they are:
1. Find Jam by seating a bullet long on a dummy piece of brass (no primer nor powder) and apply die wax to the bullet ogive and record it's base to ogive length.
2. Chamber the round and close the bolt.
3. Snap the bolt open and measure the base to ogive measurement. If it is shorter than previous measurement, this is your jam. Do it a few times with different cases to make sure.
4. Load a known powder/primer/bullet combination. I load 4 of each powder charge in 0.5 gr. increments and seat bullets at jam - .020". I use one shot of each to get barrel fouled up and also keep an eye for max pressure at the same time. You can also use these rounds to break in a barrel if you are inclined to. If I encounter pressure on the hotter rounds, I will not shoot groups with the other loaded rounds and will pull bullets when I get back home. Do not shoot in round robin style because position and natural point of aim will be compromised.
5. Shoot 3 shot groups starting from lowest to highest. All groups are shot over a chronograph.
6. Examine target and find the place where consecutive groups line up vertically and ES is the lowest and speed increases the least from one group to the next.
7. Load to the middle of the powder node and do a seating depth test.
8. Load 3 shot groups starting from Jam - 0.005" all the way out to Jam - .040" in .003" increments.
9. When you find the seating depth test that shoots the best, load towards the longest side of the node to allow more room for throat erosion.
10. Final step is to load the new seating depth and load 5 shot groups in 0.1 gr. increments 0.5 gr. on each side of node (if pressure limits are not reached). This will cover an entire grain of powder and you will be able to pinpoint where the powder node starts and ends. In the summer, load towards the low end of the node, and do the opposite in the winter.

HAPPY SHOOTING!

 

[kykamo]

Thanks for that. I was wondering because some people say that seating depth makes more diffrence to accuracy than powder charge. That seating depth is a coarse adjustment and powder charge is a fine adjustment. But if this is good for Team Papua, then it's good for me!

 

[cr5]

I start with either loading to the length the bullet manufacturer lists or I load to magazine length if it still chambers cleanly at that length. If the magazine is long enough to load to the lands I load to .02 ish off the lands to start with. This is actually kinda hard to do without a proper ogive measuring tool so I just use a sharpie to color the bullet and keep shortening the OAL until the ink doesn't get marked by the lands then shorten it a little more.
If you're measuring from the bullet tip your measurements will be mostly useless though since the bullets are not consistent.

Then I work up a powder charge that provides the greatest accuracy at around the velocity I had in mind.

After that I may go back and fiddle with seating depth again and see if any improvement can be made.

Unless your a competitive shooter my advice is to keep it simple. A lot of guys on here get so caught up trying to eliminate every variable and chasing fractions of an moa that they spend huge money on reloading tools and never seem to find their perfect load.
I've built plenty of consistent sub moa loads that required no neck turning, no annealing, no collet dies, no neck bumping, no checking bullet runout. I full length size all my brass and I only crimp for semi auto rifles (not all the time either). If you get too caught up in the chasing fractions you'll never be satisfied and you'll always be doing load development. Have realistic expectations, take your time, and be safe.
What I mean by realistic expectations is know your ability and also be realistic about the capabilites of your rifle. There are a lot of guys who think that handloading will show them 1/2 moa or better groups even though they are not experienced shooters. Others don't realize that if your rifle has a factory barrel the chances of you finding a load that shoots better than 1/2 moa are pretty slim.
Be sure to take your time at the range and fully support your rifle. Cheap (factory) barrels don't like heat and will string shots as they warm up and if your crosshairs are not steady and solid on your target you're not going to see consistent results downrange and you'll never find your magic load.

Good luck.