.02 or .03 weight change ?

Beam scale, all the electric scales I've tried sucked . Although I've never used any of the premium high end scales. I use the Hornady dispenser set about .5 grains low and hand trickle on the beam scale.
 
I fine tune the loads down to .2 increments. The nodes I see are about .5 grains wide. I'm usually doing load development in the summer so I set up on the high side of the node. This way, in the cooler months when the velocity drops, I'm near the bottom of the node.
 
I guess that's why I like heavy barrel rifles. A nice wide node to stay in so I don't fret about .1gr. My electronic scale is no where near that accurate anyways. I think it's about .2gr accurate.
IMO and from experience...lots of flyers people experience are shooter error.
 
Long range load development at 100 yards.
Eric 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!
 
When I was load developing for my 7mmRM and H1000, I found the node and did 0.2 grains either side of the mid point. I repeated the test 3 or 4 times on different days and all gave the same performance. This was after the seating depth test. Smaller cases like the .243, .2 grains made a difference. Smaller yet, 204 Ruger, 0.1 grains made a difference. Basically, 3% to 5% of case volume was the edge of performance change.
 
I will mostly agree with, what seems to be, the consensus of the group. When I develop my loads I am looking for a wide node. Using the ladder or, less favorable, OCW you will find the edges of the nodes. I want my load to be in the middle of that. I will recheck it to ensure accuracy and good es veclocity. So while I agree with not wanting a load that is dependent on a .01 grain powder change you still need to be in the middle of the node which will require you being accurate with your charge to .01-.02.
 
I figured you added an extra 0 to the measurement 0.00 vs 0.0

I have scientific scales that can read to the mg but they are $$$ and are much much harder just to setup. No flourescnet lighting, zero emf around. No vibration. Needs contrete or very heavy dampend steel table hundreds of pounds. It can read resolution to .001 grain but accuracy is 0.01, with a mg beimg 0.0154 grains. Has a hood to stop air flow etc.

Do not forget just becuase a scale has a certain resolution is not the same as its actual accuracy which is almost always less.
 
Last edited:
Warning! This thread is more than 7 years ago old.
It's likely that no further discussion is required, in which case we recommend starting a new thread. If however you feel your response is required you can still do so.

Recent Posts

Top