Lost and Confused regarding Load Development

[R.Morehouse]

First Off.....Nice Gun.....For banging steel with the Dasher, if you can get 1/2" accuracy at 100yds, that is only 5" at 1K..........That will bang steel between those yardages quite effectively.....Just Sayin'

Since Garmin came out with their chrono.,I set it up every time I go shooting. It's just too easy to do and it adds to the fun for me.

Regards
Rick

 

[Dgd6mm]

A node is not a velocity flat spot on a chronograph.

^^^^^^^^^^^^^^

 

[Doom]

NODE:
For most of us a node is a powder charge range and seating depth range where the POI at short range is not sensitive to small changes in either. It is predominately a function of internal ballistics (seating depth) and barrel harmonics (barrel time).

 

[JEFFPPC]

The more you read here the more apt you are to become even more confused. My advice is find a successful competitor in your area a follow what he does. Get away from the typewriter experts. Some good advice but hard to sort it out of the crap.

 

[joshb]

I follow Erik religiously. That is part of why I'm confused...he talks about finding the nodes, but then others dismiss those velocity nodes as a myth

I completely disagree with the idea that there aren’t nodes! Your method is exactly what I’ve been using for years and ALL of my rifles/barrels have nodes. Too many people want to be Utube celebrities and buck conventional wisdom to get attention. Ignore them! Listen to Eric!

 

[ShtrRdy]

The term "node" comes from the description of a resonating structure.

Node (physics) - Wikipedia

en.wikipedia.org

The way we use the term in load development isn't correct but it can imply a point in time where the object of interest stops for a moment. In the case of firing a rifle, we are interested in having the bullet exit the muzzle at a point in time where the muzzle has reached an extreme position and pauses before it starts to move to a new position.

 

[Webster]

I'm a relatively new to handloading. I've only done load development with hunting rifles with okay results. My go-to method was

1. Last up to published max looking for pressure to determine a safe place to test chargeweights
2. Shoot a ladder test to find flat velocity flat spot "nodes"
3. Test different chargeweights within the node to find the amount of powder that yields the lowest SDs and ESs
4. Using the chargeweight with the best velocities and then test seating depth using groups.
5. Hopefully be happy

Now I've been listening to the Hornady podcast and they definitely drive home the idea that velocity notes are a myth...that with a large enough sample size, velocity increases linearly with increases in powder. So now I'm lost. I don't really hear them providing an alternative method, except trying different combinations of bullets/powder/primer. Problem I have I just build a 6 dasher that is purely for fun and hitting steel, and I've bought enough primers (CCI 450), bullets (Berger hybrid 105), and powder (varget), all with matching lot numbers, to last me the life of this barrel. So with that, can yall give me some insights into how you would develop a load? I keep hearing/reading how easy it is to load for the 6 dasher. I tested for max chargeweight today and started hitting pressure at 32.2gr of varget, where my velocity topped out at 2935fps. Was hoping to maybe get a bit more out of my 28" barrel. So since there are no such thing as velocity nodes, then what...just load up to something like 32.0gr and just move straight to bullet seating tests?

Guys might be taking about different kind of nodes? A FPS that seems to shoot well with a particular bullet and powder. Based on increasing the load how the shape, size and location of the group change? I don't care about the term node, I just want a small group.

 

[nwmnbowhunter]

I follow Erik religiously. That is part of why I'm confused...he talks about finding the nodes, but then others dismiss those velocity nodes as a myth

The big take away is "consistent" velocity.

Only change one thing at a time.

If it gets smaller, keep going in that direction.

If it gets bigger, then stop, or go other direction.

IF NOTHING MAKES SENSE, RE-TORQUE EVERYTHING. AND THEN CHANGE POWDER OR BULLET.

I have one bullet that people love and I've tried in 5 rifles and cannot get it even close to other what other bullets shoot.

pressure test first.... then you know safe range (10 shots about)

Seating depth in an area where they seemed to impact similar on pressure test. 5 groups of 3. Follow berger seating depth guidelines. (15 shots).

Then powder charge go up or down by 0.02.... if they get smaller keep going until they get bigger or you reach pressure. (15-20 shots)

At this point you should be about 40-50 shots and have a really good idea of the what the rifle can do.

If it isn't shooting great then change powder or bullet and repeat.

 

[6ShotsOr5?]

The term "node" comes from the description of a resonating structure.

Node (physics) - Wikipedia

en.wikipedia.org

The way we use the term in load development isn't correct but it can imply a point in time where the object of interest stops for a moment. In the case of firing a rifle, we are interested in having the bullet exit the muzzle at a point in time where the muzzle has reached an extreme position and pauses before it starts to move to a new position.

There are wide differences in bullet velocities and barrel lengths to consider. Some people think the bullet is gone before the muzzle has time to start oscillating. Others disagree. I’m squarely in the “I don’t know” camp on this issue.

 

[nwmnbowhunter]

Also what do you mean by pressure?

And take any emotion out of your process. It either shoots smaller or it doesn't. Go through your process and if you are satisfied with results... great. If not, then change.

 

[wright brothers]

Thanks for explaining.
I Assume my upstairs mode produces more velocity. It also has larger volume. But I own no meter.

 

[nwmnbowhunter]

Here is a seating depth test on my hunting rifle.

The big take away for me is that all the impacts are basically the same in reference to aiming point.

I did verify -.040 was the best at distance.

But for a hunting rifle this is very forgiving

 

[K22]

If you were confused before, I can only imagine the state of your mind now.

In my humble opinion, you have over complicated a relatively simple process.

1. First, establish an accuracy goal to meet the needs of your chosen shooting discipline.

2. Select a powder and bullet that has a history of top performance for your caliber of choice. Choose a seating depth recommended by the bullet manufacturer or one that fits the magazine and does not jam the bullet into the lands. In the absence of other reliable information, I start at .020" off the lands.

3. Select 3 to 4 loads from published date for this powder / bullet combination starting at the minimum but avoiding the maximum charge. Fire 3 or 5 shot groups with each test load. If possible, use the bullet manufacturer's published load data.

4. Select the one the meets your goal. Retest the one you selected with a few more test groups (I like 3 test group to verify the load chosen).

5, Go have fun shooting steel.

 

[Mulligan]

Good point.
Rifle:
Lone Peak Fuzion action
28" CRB Comp barrel
MDT ACC Elite chassis
Triggertech Diamond
Razor Gen 3 6-36x56 MOA

Components:
Alpha Brass
CCI 450 primers
Berger 105 Hybrid
Varget Powder

I anneal after every firing with AMP. Headspace is .0015-.002". Tension is using a PMA mandrel.

View attachment 1619236

Awesome, thanks for getting back to us with the details.

In one of the posts, @William Vogel gave you his GO-TO load, you should to thank him, that is really good advice. I recommend to new dasher shooters who have a good strong action to start at 31.2gr of Varget and work up from there (for 103-108gr berger vld style bullets). If the gun will not shoot with either 31.3 or 31.7gr of Varget behind your 105 Berger (assuming you know how to pull a trigger). You may have a mechanical problem (bedding, actions screws hitting something, something loose on the system that rattles when you shoot, trigger acting up, scope mounts, rings or the scope) If you are chasing velocity, please discard my information entirely.

As you know, your target is the most reliable info you are getting.

CW

 

[Doom]

...

1. First, establish an accuracy goal to meet the needs of your chosen shooting discipline.

4. Select the one the meets your goal. Retest the one you selected with a few more test groups (I like 3 test group to verify the load chosen).

5, Go have fun shooting steel.

A lot of wasted time and frustration can be circumvented if reloaders in general would do item 1 and 4 above based on realistic expectations. Expecting a factory hunting rifle to consistently produce sub 1/2" 100yd groups isn't realistic. Some might do it but it wouldn't be a realistic exception. While it might be nice to say you have a 1/4 MOA rifle or a single digit SD the fact is if you can't shoot it, it doesn't matter.

For the average shooter worrying about the minutia of reloading that most high level competitive Bench Rest and F-Class shooters do in reloading isn't likely to reap much if any reward on target. In general buying quality components should be #1 on any reloader's list of priority. Custom/speciality dies, ultra precision scales, etc isn't This is especially true if the rifle is an off the rack factory rifle, high end or low. The competitive shooters' rifle has a custom barrel designed for competition and likely a custom chamber optimized to shoot a specific or limited range of match bullets. In most cases the rifles weigh north of 13 lbs to near 30 lbs.

So we get to item 5. Whether its paper or steel or clay pigeons on a berm, time spent shooting is likely to improve the shooters results more than hours of slaving over sorting primers and weighing bullets.

 

[Jeff Porter]

You are shooting a Dasher with a quality barrel, 105 Berger's, 450 primers and Varget and assuming quality brass from Lapua or Alpha or Peterson. you are 90% of the way there with these 6mm BR family loads. Easy button would be to dump 30.2-30.5gr Varget in the case and seat the 105 to 0.020" off touch and shoot a five shot group. If it is not 2850-2900 fps with 0.75 moa or less, I would be surprised. Your combination of powder and bullet will group well over a large range of powder weights in a Dasher. Also, search for some of the recipes that winners have used in the Bulletin section of Accurate Shooter. you will see a lot of commonality.

I shoot a 6 BRAI and this is how I am going to work up a load for a new barrel with 105's.

Do a charge ladder with a chronograph with three shots of each charge weight at an interval you are comfortable with using at as long a distance you have available. 200 works, 300-600 is better but at 100 yards, the difference is harder to see. Barrel life and components used come into play so you don't have to check every 0.1 grain from 28-32 grains. 1% of the max is what I use or 0.3gr. I load at the range so I can shoot some single cases of charge weights as sighters to work up to my starting charge which is usually 90-95% of max. This is usually 6-7 powder charges over a range to evaluate. With 32 gr Varget as a suspected max, I will start at 29.0 for single shot sighters and velocity check at 29.5 and 30.0 and start the ladder about 30.3 grains.

Do not to look for velocity flat spots as you noted they are not real but are artifacts of small sample size.
( The physics of adding more gas to the same volume and not changing the force/ velocity of the bullet is just not possible. )

During the ladder I am wanting to determine where a max charge weight is where I see primer issues or feel heavy bolt lift.

After firing, I look for point of impact shifts at the center of the three shot groups at each charge. I use an E target, others color the bullet tips with marker to track these POI.
You are looking for a charge that gives you a desirable velocity ( not a powder puff that will get blown around at distance but not on the edge of maximum charge that will be risky for brass and rifle life in the long term when things heat up or the chamber gets dirty) where a set of three consecutive 3 shot groups have a similar Point of Impact.

While the powder node is fictitious, this settling of POI based on barrel harmonics and positive compensation due to muzzle movement at distance is what you are looking for. This is the basis of the OCW load development too.

Once you have chosen a powder charge in the area of the POI "node". Proceed to seating depth testing to fine tune group size. Berger has a good tool for determining the seating depth using about 0.030" steps but you will want to shoot some at smaller increments once you identify the best from their gross depth changes. My experience with Hybrids is they will group well about anywhere but they will group better at some seating depths than others.

While fire forming a new lot of brass I was using 108 BT Berger 30.2 Varget seated to where the boat tail is at the neck shoulder junction ( did not care if it was jumping or slightly jammed). New barrel with less than 200 rounds is printing 0.3 moa groups at about 2830fps. One test - done. I had the load at the velocity and the group sizes I need for sling shooting. I am saving the fire forming for a match as it is shooting well enough already.

Don't over think it. Keep a safe pressure and find a recipe of powder, primer, brass, and bullet that goes where you point it.

 

[fattybinz]

Also what do you mean by pressure?

And take any emotion out of your process. It either shoots smaller or it doesn't. Go through your process and if you are satisfied with results... great. If not, then change.

Biggest sign was a heavier bolt lift at 32.2 grains. Everything else looks okay...ejector is leaving a ring but no wipe on it. Slight cratering in the primer firing pin hole but the primer itself isn't being flattened.

 

[nwmnbowhunter]

Biggest sign was a heavier bolt lift at 32.2 grains. Everything else looks okay...ejector is leaving a ring but no wipe on it. Slight cratering in the primer firing pin hole but the primer itself isn't being flattened.

Yeah that's a lot of pressure. I would stay away from that!!

 

[fattybinz]

Yeah that's a lot of pressure. I would stay away from that!!

I've had a few members above recommending working off of 31.5 gr. Is that far enough in your opinion from those pressure signs at 32.2?

 

[K22]

A lot of wasted time and frustration can be circumvented if reloaders in general would do item 1 and 4 above based on realistic expectations. Expecting a factory hunting rifle to consistently produce sub 1/2" 100yd groups isn't realistic. Some might do it but it wouldn't be a realistic exception. While it might be nice to say you have a 1/4 MOA rifle or a single digit SD the fact is if you can't shoot it, it doesn't matter.

For the average shooter worrying about the minutia of reloading that most high level competitive Bench Rest and F-Class shooters do in reloading isn't likely to reap much if any reward on target. In general buying quality components should be #1 on any reloader's list of priority. Custom/speciality dies, ultra precision scales, etc isn't This is especially true if the rifle is an off the rack factory rifle, high end or low. The competitive shooters' rifle has a custom barrel designed for competition and likely a custom chamber optimized to shoot a specific or limited range of match bullets. In most cases the rifles weigh north of 13 lbs to near 30 lbs.

So we get to item 5. Whether its paper or steel or clay pigeons on a berm, time spent shooting is likely to improve the shooters results more than hours of slaving over sorting primers and weighing bullets.

Amen - it's called internet disease.