Question on Load Development

[Jayhawker]

Hello:
I'm in the process of developing a load for my new .223. At this point, I've narrowed it down to two different bullets with loads I picked from my handbooks on an arbitrary basis. I also set the COL by the book. Now I'm ready to go ahead and experiment with different loads with the chosen bullets as well as try to start setting the bullets different distances from the lands. Does it make any difference which I do first? I'm trying to do one thing at a time.

Thanks for any assistance.

Pete

 

[taliv]

unless you've got a match chamber and are trying to get benchrest-type accuracy, don't screw around with OAL. just seat your bullets where you can crimp in the cannelure.

in either case, start with the amount of powder first

have fun,

 

[ojibweindian]

I seat my bullets at the cannalure and apply a crimp. Start your powder charges about 10% under max and go up in .2gr increments. Load 5 rounds and shoot for groups.

At some point, you'll find the sweet spot. Anything above that will open your groups up dramatically.

 

[swingset]

When you test your loads, do a "round robin".

As your barrel heats up during shooting, it will affect your POI, so to factor this out of the bullet's performance, shoot like this:

Say you have 3 different loads to compare. put up as many targets as loads you are comparing. Take 1 round of load #1 and shoot it at your first target. Now take 1 round of load #2 and shoot it at the next target. Take 1 round of load #3 and shoot it at the last target. Repeat like this until you've shot 15 rounds. Now, compare the groups.

FWIW, I never crimp my rounds and have yet to have an adverse effect from it. Don't see a need unless you're handling your ammo in battlefield conditions, but that's just my SOP.

 

[Darkside]

I second the "Round Robin" method. First, I select the bullet for it's intended target. Second; look in the loading man. of the bullet manufacture for a load that is as near 100% or more case capacity. Some manufactures list a "most accurate" load, which would be a good place to start. Using the sugested components I will work up .2gains at a time until I reach the max load for my rifle. I shoot these "round robin" style until I find the sweet spot or reach the max load for my rifle. I take the most accurate load of the batch and adjust the COL to see if I can tweek a little more accuracy from the load.(sometimes it does make a differance) I do not have match grade barrels on my rifles, but I have set accuracy goals for my rifles baised on the intended use. If the load tested meets or beats the goal I stop playing around and load-em-up.

Darkside

 

[Steve Smith]

Off to the Handloading forum with this!

 

[30Cal]

There are ways to make several changes at once and to be able to quantify the contribution of each parameter that's changed, but it takes a little while to set up and involves some statistical math. "Design of Experiments" is the tool that would get you there.

I would first choose bullets based on the rate of twist of your barrel--no sense trying something that most likely isn't going to fly. I step my powder by 0.4 or 0.5grs and try to shoot at least 4 groups per load. If the load only needs to perform for 3-5 shots, then go ahead and try to remove barrel heat from the equation. I shoot 55-88 round matches, so a load that can't hold up past 5 rounds is of no value to me.

My goal is to find loads with a very large sweet spot--if it shoots well hot and cold and doesn't seem to mind typical variation that I get out of my powder measure, then that's a good load and I tweak from there. If I have to individually measure each charge, apply a certain amount of crimp and have to seat to a particular distance just to get it to shoot well, then I chalk it up to "interesting, but not worth chasing."

Ty