load development

GuroChris

Well-Known Member
Joined
Mar 18, 2020
Messages
127
Location
Foot of the Blue Ridge in the shadow of Gun Mtn
Here's how I did it. You guys let me know how I can improve.

First was brass prep, I had a bunch of once fired Federal brass. Annealed,cleaned, de-primed and sized then trimmed to length.
I annealed the brass with a propane torch. I know thats not the most repeatable method but funds wont allow an AMP annealer. Other gear was corn cob media in a vibratory tumbler with a shot of Brasso in the media. Then universal decapping die from Lee. On to sizing with Redding S-type dies. 2 thou of shoulder bump and 2 thou of neck tension. After that RCBS case trimmer its time for priming and charging.

I used CCI 200 primers and tested charge weights of IMR 4064 from 42.4 grains to 44.2 grains topped off with a 165gr sierra tipped game king bullet.

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I decided to go with 42.8 since I'm not super worried about getting max velocities.

Next is seating depth. I know lots of guys do it the other way around but I cant find a consensus for one over the other.
I tested in increments of 3 thou to find a node which you can see develop in the photos. The first photo shows some promising groups but the rounds didnt feed from the magazine even though they all fit into the mag fine. The loads in the second photo fed much better.

The worst part was the last shot of the last group. I got too excited after I saw the first two touching and smacked the trigger a bit.

I'm fairly happy with the overall result but how can I improve the process?

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Well...looks like it is shooting very well...
Most people on here don't set back shoulders until after 2nd or 3rd firing....
When most consider the brass
'truly fitting' the chamber.....
 
I've found load development at 200 really helps me ,if conditions allow. I've been fooled by good100 yard groups at longer distances
 
Good point. Here's how I do it most of the time. Velocity ladder looking for pressure at longest desired coal. Drop down a gr or 2 and do seating test for accuracy, fine tune with a .01 ladder if necessary
 
Initial seating was OAL of 2.800. that was the max OAL listed in the manual.

But that's sort of the starting dilemma. charge weight or seating depth first? If i pick a random powder charge then do seating depth first, them am I not also changing 2 things at once? Aren't seating depth and charge sort of connected? And picking a middle charge weight is sort of random. When I use Book COAL at least I have a SAMMI standard to start from. Either way its all just a place to start.

I did all this without using a chronograph. I figured speed didn't matter unless it was accurate first.
 
I pick my velocity/pressure and then adjust my accuracy with seating depth. Powder charge works for accuracy too and I've done it both ways. I use powder ladder for accuracy with hammer bullets with good success vs seating depth for accuracy. It just depends
 
There are 2 independent things tuned by load:
1. Bullet release timing w/resp to barrel vibrations
2. Attributes of best powder burn

Bullet release timing is dominant to results, and normally adjusted with powder, our finest of all adjustments.
It is unlikely that a tightest grouping powder load just happens to be burning with the lowest ES/SD.
It could be, but less likely, as there is no reason for best bullet release timing to coincide with best powder burn.
If you really really want them to coincide, then you need a barrel tuner and understanding of proper load development with one.

There are several independent prerequisites to load tuning:
1. Optimum Primer/Primer Striking
2. Optimum Seating Depth
3. Stable Cases

Prerequisites are [course] items that should be cleared of issue before moving to your [fine] powder development.
Ideally you can work on these prereqs at your worst potential powder load. This way you're not coming into or out of dominant barrel timing (a node) while you're trying to see optimum primer or seating.

If you can get your brain to accept what I'm saying here, then you'll more clearly see your way around tail chasing.
By the time you get to powder development, you should be past all other factors, and simply adjusting powder (right to the kernel) for best.
In this case best is either tightest grouping, or if using a tuner then best can be lowest ES/SD, followed by bullet release timing as adjusted by the tuner. Simple,, orderly,, logical.
 
H Chris , Sorry I guess I joined the thread very late. I didn't catch the caliber, and if you are separating your cases by weight after they were all prepped and uniformed?? For my 270 Win i like 185.0 to 185.3; then 185.4 to 185.6; then 185.7 to 185.9. the 186.0 to 186.3 ect. I like three tenth of a grain for Deer Hunting. Just wondering how you felt about adding that step to your already excellent load development ??
 
Initial seating was OAL of 2.800. that was the max OAL listed in the manual.

But that's sort of the starting dilemma. charge weight or seating depth first? If i pick a random powder charge then do seating depth first, them am I not also changing 2 things at once? Aren't seating depth and charge sort of connected? And picking a middle charge weight is sort of random. When I use Book COAL at least I have a SAMMI standard to start from. Either way its all just a place to start.

I did all this without using a chronograph. I figured speed didn't matter unless it was accurate first.
Remember book COAL means nothing unless you're using the exact same bullet in the exact same chamber they used, which you are not. Your rifle's chamber leade is likely not the same as the test barrel. Also, every bullet type's ogive is in a different place relative to the tip of the bullet. So, what to do - this one way at the macro level

1.) Figure out where your max CBTO is using which ever method you deem worthy using every bullet you use before loading anything with that bullet (where the bullet ogive touches your rifle lands)
2.) Figure out where some good velocity/pressure nodes are with the bullet you chose. I usually use a safe CBTO like 0.040in off the lands to avoid bullets jamming on me while doing this step, see step 1 for the starting point of the lands.
3.) Do seating depth tests using the powder load you discovered in step 2 and the max CBTO found in step 1

Using this method I seem to spend way less components than any other basic approach. One of the big things you'll notice during step 2 are the velocity/pressure jump points that you need to stay away from to get good ES/STD. Plus you will be recording lots of good info on your rifle while doing this.
 
H Chris , Sorry I guess I joined the thread very late. I didn't catch the caliber, and if you are separating your cases by weight after they were all prepped and uniformed?? For my 270 Win i like 185.0 to 185.3; then 185.4 to 185.6; then 185.7 to 185.9. the 186.0 to 186.3 ect. I like three tenth of a grain for Deer Hunting. Just wondering how you felt about adding that step to your already excellent load development ??
This rig is a .308 win. nostalgic for me and kills deer dead
 
Remember book COAL means nothing unless you're using the exact same bullet in the exact same chamber they used, which you are not. Your rifle's chamber leade is likely not the same as the test barrel. Also, every bullet type's ogive is in a different place relative to the tip of the bullet. So, what to do - this one way at the macro level

1.) Figure out where your max CBTO is using which ever method you deem worthy using every bullet you use before loading anything with that bullet (where the bullet ogive touches your rifle lands)
2.) Figure out where some good velocity/pressure nodes are with the bullet you chose. I usually use a safe CBTO like 0.040in off the lands to avoid bullets jamming on me while doing this step, see step 1 for the starting point of the lands.
3.) Do seating depth tests using the powder load you discovered in step 2 and the max CBTO found in step 1

Using this method I seem to spend way less components than any other basic approach. One of the big things you'll notice during step 2 are the velocity/pressure jump points that you need to stay away from to get good ES/STD. Plus you will be recording lots of good info on your rifle while doing this.


Is all that strictly necessary if I'm mag feeding the rifle? I have a Hornady OAL gauge and have used the "Wheeler method" for finding lands before.

I'm all for learning from the process but are the extra components worth the education I get from the endeavor if I'm not really going to use the rifle in that manner? Is the juice worth the squeeze?
 
Is all that strictly necessary if I'm mag feeding the rifle? I have a Hornady OAL gauge and have used the "Wheeler method" for finding lands before.

I'm all for learning from the process but are the extra components worth the education I get from the endeavor if I'm not really going to use the rifle in that manner? Is the juice worth the squeeze?
That's up to you to judge. I don't know what your desires are with this particular rifle. My post was very generic outlining the basic approach I've found and many others have found to systematically arrive at a good result fast. This method will use way less components in most cases to arrive at a good performing load than randomly changing powder and seating depth at the same time. Now if you're saying you want to load to mag length only then you cut out the seating depth step. Shooting a ladder will still allow you to find pressure nodes. Then you can pick powder loads that are in nodes instead of one that might be on a pressure jump point. I did this with my 375 Ruger because I decided to crimp. I picked a specific length then shot a ladder at that length crimped and decided on powder charges. Then shot the powder charges and went with the most accurate from those.

Its like Coues deer hunting. Glassing deer up off tripods with good glasses then closing the distance to a comfortable shot distance is way more effective than randomly walking the hills trying to jump one and get a quick shot. Sure, occasionally you might jump a buck and get a shot but by glassing and knowing they are there is still a higher % approach. Just like randomly picking a charge and seating depth might occasionally produce great results.
 
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