Powder charge OR Seating Depth.........

[Bristleback]

Sure appreciate all the input on this site.

Is there a "rule of thumb" so to say in working up a load..........finding a powder charge that "groups" the best.........THEN work on seating depth?........a different approach? When do you decide to change primers?

I'm certainly willing to work up loads in .2gr increments to find THAT SWEET load......ie 44.0, 44.2, 44.4......etc

I'm wanting to FINALIZE a couple guns/loads, have turrets built and have them ready and waiting to head to the field .

 

[jonbearman]

Tell us a little about the gun and the cartridge.This will help us give our opinions.Generally I set the bullet off the lands about .020 and load a few more per increment and touch the lands when possible. However I dont know what we are talking about as per caliber ,type of barrel(custom,factory etc).What type of chamber(tight neck,no turn) etc.

 

[NorCalMikie]

You can go either way. Powder charge or seating depth. Make sure you do "only one" at a time or you'll end up chasing your tail trying to figure out what made the difference. And you might go in .1 steps at a time on your powder charge.
When you find your best powder charge, (best group) then you can adjust seating depth to see if it makes any difference. And you don't need to be fast to be accurate! A lower powder charge will give you more "wiggle room" if it gets hot outside. No need to run a hot charge and not have anywhere to go but down.

 

[FroggyOne2]

What I usually do is decide on a starting load and conduct a ladder test. With the bullet seated where the bearing surface of the bullet is seated just above the neck/shoulder junction. Once I have found something that appears to be working, then play with the seating depth. Change one aspect at a time when trying to find a load that will work (IE seating depth or powder charge, or a change in primer) Never change two componets at one time.

 

[BoydAllen]

I make a guess on seating depth, based on my experience, and then work with powder charge. When I have gotten as far as I can with charge, I go back and fine tune seating depth.

 

[Bristleback]

JB, thanks:
Savage 204, not certain I'd get a turret built for this, maybe.
Savage 22-250
Keriger barrelled 6x284 1:12
Kreiger barrelled 6.5x284 1:8.5

NCM, thanks, guess I was looking for a general SOP direction......what most have found sucessful. Fully understand only changing one component at a time.

F12, thank, i've read about ladder test, but have never "conducted" one....

Hey Boyd, thanks.

I have zero interest in BR shooting, but certainly wanting to learn techniques, systems, etc to develop the most accurate loads for my hunting rifles.
Again, thanks, I appreciate the input.

 

[TonyR]

I don't hunt but I have developed loads for friends that do. I believe that the same principles apply. A ladder test is always the place to start because barrel harmonics seems to dominate all of the other factors. In my experience, the most important difference to account for is the response of typical sporter-weight barrels to heat. My F-Class barrels allow me to shoot 20-30 shot test strings without difficulty because that is what we do in matches and the guns are designed accordingly. On the other hand, the sporter barrels I've worked with start to change point of impact after more than about 3 shots; so I shoot my 2 or 3 shots at each powder charge and let the barrel cool off between strings until I've completed the ladder. Once the nodes have been located, I go back and confirm the nodes usually by shooting pairs of the best powder charges on a cool, dirty bore. I believe that 2 or 3 shots close together on a cold dirty bore is what is needed in most hunting situations, at least I would hope so. Doing it this way can be time-consuming but, so far, this procedure has worked out pretty well with a 308 Win, a 338 Lapua Mag, a 375 H&H Magnum and a 416 Rem Mag I've done it with.

 

[coyoteklr]

i don't br shoot but as you said like to have the most accurate load i can work up..
i use to get pretty anal retentive but life has gotten too short for me to worry much about weight sorting cases or bullets.....
i use manuals that have accuracy loads and then the fun begins.....
I don't necessarily use the powder recomended in the manuals but start with a load that will give me about the same MV....
i use ball power not stick because it meters so well out of my redding 3br powder thrower....
i find a powder that will give me a good group and if i'm not happy with that i will change bullets..... if not happy with that i will change powders.... when i find the right combo that i like i start messing with col.....it seems like that trying to adjust a regular seating die is a lesson in frustration... so i have gone to the micrometer style of seating die.. one thing that i have found is with barnes tsx and ttsx is that they like to be jumped at a min. of 80 thousands up to 125 thousands and they don't like to be pampered with the speed thing...
I use those for hunting and for varmits i use nosler BT and hornady v-max and seirra match

 

[mikecr]

+1 BoydAllen

 

[RonAKA]

I shoot a few groups with a potentially good load based on sweet spot velocity research, using 0.010" jam, 0.010 jump, and 0.020 jump. I pick the best seating depth and do the full ladder. From the ladder I pick the best load and then try seating depths again to optimize it.

 

[pills]

I was doing the same thing while working up a .222 load in my Rem. 700. Found a good combo of 4198 and 52g Matchkings and had the bullet seated .002 off the lands. All was well it was shooting .5xx for 5 shot groups at 100yds good enough for me as I don't shoot competition. Then last week I started to play with seating and slowly worked shorter in size. The last groups I shot (the shortest, near book OAL) shot the best .385 for 5 shots. ??? This goes against everything that I have read, but so far it's the best group I have ever shot with this gun. I was kind of confussed, I guess I need more testing.

 

[BoydAllen]

I have never gotten my best groups just off of the rifling. For my .222s I use a depth of .006 to .010 longer than touch, depending on the shape of the bullet. Of course you will need to do a fresh workup of powder charge, because seating into the rifling will increase pressure, but not dangerously so, unless you are already shooting a load that is too hot.

 

[lynn]

Seat them as long as you can.
Powder charge first seating depth second and primers third.
Use 1% of your expected final load for your increments.That means loads from 30-39 grains use 0.3 grain increments.40 -49 grains use 0.4 grain increments.
Only go in one direction on your seating depth to keep things easy and simple.
My opinion.
Lynn

 

[lynn]

Tipper99
Go to Kenton Industries to see the turrets.
Lynn

 

[1shot]

+2 to BoydAllen 1st post. I NEVER seat to "just touch" as there are enough variables in bullet bearing surface to get you into trouble. Refer to Eric Steckers article on the Berger web site for seating bullets and you will be surprised at how quickly you will find "the load". Primers are the lastthis I test. After I have settled on a powder/bullet & seating depth, I'll load 3-5 each and test 3-4 different primers. Every time I do this though, the Wolf primers always win.
I hope this helps,
Lloyd

 

[DougMH]

Sure appreciate all the input on this site.

Is there a "rule of thumb" so to say in working up a load..........finding a powder charge that "groups" the best.........THEN work on seating depth?........a different approach? When do you decide to change primers?

I'm certainly willing to work up loads in .2gr increments to find THAT SWEET load......ie 44.0, 44.2, 44.4......etc

I'm wanting to FINALIZE a couple guns/loads, have turrets built and have them ready and waiting to head to the field .

This is always a dilemma isn't it. Here's how I approach it.

1) I perform my ladder test with bullets seated "on the lands"
2) I then perform my bullet seating depth test using the "sweet" load from 1)
3) I then go back and do another ladder test to confirm that the "sweet" load from 1) is still the best when using the "best" seating depth from 2)
4) I then repeat steps 1) - 3) 50 times to confirm.
5) I then replace the worn out barrel.

I don't really do 4) and 5)... but I do 1) - 3)

 

[NC-Shooter]

I know I am resurrecting the dead with this thread, but I wanted to point out that Berger Tech Support recommended I find the bullet seating depth first (with the min charge weight) and then find the accuracy node in the powder charge second. The logic is that when you change the bullet seat depth you also change the remaining case capacity that the propellant can initially expand in, which changes pressure. The optimum bullet seating depth will always be the same until the throat wears regardless of charge weight. This is untested by me, but makes sense IMO. Although it is hard to argue with the tradition of finding the charge weight first and then find the optimum bullet seat second, because it seems to work just as well for decades.

 

[mikecr]

It depends on if you intend to do a full seating test(coarse) or just tweaking/powder group shaping.
If doing full seating testing, you can do it during fire forming of cases. Then after powder, tweak seating for best grouping.