Rifle Load Development - Is this the best way to do it?

[DannyLandrum]

Think this is the best forum for this.

Acquaintance of mine swears by this method but I didn't get all the details from him - what say you?

Generally speaking, the idea is to hone in on a COL the rifle likes *first*, then secondarily hone in on a velocity (powder charge) it likes, with a given bullet and powder combo you are trying, as follows:

He will load up say, 3-5 rounds in multiple COLs (each), with a middle-of-the road (medium-high) powder charge which seems the most common or popular for that bullet weight generally:
1. 5 rounds .050 off the lands
2. 5 rounds .040 off
3. 5 rounds .030 off
4. 5 rounds .020 off
5. 5 rounds .010 off
etc - maybe 5-6 different COLs

Something like that - just a smattering of likely COLs that should be best. Is there a better increment to use for this than .01? Such as .005, to better reveal the pattern? If you do this, what's the best method of picking the powder charge for this load - 10% off max, 5% off, or what?

Then shoot those groups to find the best group - this is the COL the gun likes. Stick with that and don't change barring something unusual.

Then and ONLY then does he mess with powder charges at that given COL. So, supposing it likes .030 off lands, go back to the house and load up some rounds (3-5 each) in 1 gr or 1/2 gr increments, such as (starting about 10% below max):
1. 5 rounds at 50.0 gr (for example)
2. 5 rounds at 50.5 gr
3. 5 rounds at 51.0 gr
4. 5 rounds at 51.5 gr
5. 5 rounds at 52.0 gr
etc - maybe 6 or 8 total different powder charges.

If you do this, do you generally use 0.5 gr or 1.0 gr for your increment with "full power bottle necked cartridges"?

So the main thing to take away is that COL is more important than powder charge for accuracy - legitimate conclusion / method? Any better ones? Thanks.

 

[cheygriz]

For "super accurate," match grade barrels, COL is indeed more important

For normal hunting rifles, the difference, IME, isn't worth the effort.

I just set hunting ammo .010 off the rifling and call it good.

 

[.308 Norma]

I just set hunting ammo .010 off the rifling and call it good.

Me too - if it fits in the magazine.

 

[Blue68f100]

I've always done the ladder/ocw work first using factory recommend OAL. Then I start adj the OAL to tighten the group. Most mfg these days have it where you can't reach the lands, unless you hand feed. And that's not a given, since some are so long you will barely have the bullet in the neck. If your gun has a magazine you have to fit it, unless you hand feed. I do step in 0.005" increments. With most the the ELD's (aka, long skiney bullets) are not sensitive to jump.

 

[Nature Boy]

I do powder charge first, then seating depth, then primer type.

I’ve been reading lately about more people who advocate for seating depth first so I may give it a try

 

[SamT1]

I always find a powder charge accuracy node and go from there.

Go up by 1 grain of powder, find the node and use tighter increments inside the node. I start about half way through the data and go to max. If I need to be on the bottom end that’s time to cull a powder.

For most of what I do I load at max magazine length from the get go. But if I can go longer I usually run at .020 and rarely deviate from that. I suppose if i was competing or having an issue that I would spend more time on the Oal.

I generally run powder that I like from prior experience, but I do have as good of selection as any reloading shop to try if needed.

But like clockwork a guy can almost just load 1 grain off max load and hit the jackpot when using reputable components.

 

[Slamfire]

A guy shooting a bench rest rifle will see variations in variables that someone shooting an F class rifle won't see. And a F class rifle shooter will see things in his ammunition that a sling shooter won't see. And a sling shooter, firing a heavy barrel target rifle, will see things that you won't see in a hunting rifle. And if you are shooting offhand, you are just happy to hit the black!

Offhand, 100 yards, with a K31. Just happy to be on paper!



The greatest variable is shooter skill.

 

[jmr40]

If it fits, it gets fired. All of my best loads are stolen from others who I let do the field testing. Asking questions here and at other places is a goldmine of information. If you find a lot of people getting excellent results with 45 gr of ABC powder and a 180 gr Remchester bullet chances are good that combo, or something very close will work for you. I'd never blindly use another persons loads, but after checking with a manual to verify that load is indeed within specs I get started.

But like clockwork a guy can almost just load 1 grain off max load and hit the jackpot when using reputable components.

That is pretty much what I've found too. That is where I usually start, but will experiment with 1/2 gr off max, and go right to max to see what happens. Most of the time 1/2 gr below max is the best compromise between the speed and accuracy I want.

I load the bullets just as long as I can that will still fit in the magazine and chamber. If they don't fit, I seat the bullets deeper until they do. If I don't get the results I want I can always seat bullets a bit deeper, but I've never found it to help. I've always gotten best accuracy with the bullets seated as long as possible.

As a hunter, not a target shooter, my goal is to consistently put 3 rounds into an inch with the fastest safe load. In a hunting situation any more accuracy isn't relevant when fired from field positions. I'm not going to waste time, bullets, or powder trying to squeeze the last .2 MOA rifle. But I've been able to get loads that will usually better than 1 MOA, with loads either right at max or about 1/2 gr below that.

If a certain powder is not capable of giving me 1 MOA at speeds that at least match common factory loads with that bullet weight then it is time to try another powder.

 

[ArchAngelCD]

I do powder charge first, then seating depth, then primer type.

I also do it that way but is there really a difference? How can it matter if you find the OAL first of the powder charge? In the end you will be at the same point. I think you will get there faster starting with the powder weight first.

 

[Grumulkin]

Acquaintance of mine swears by this method but I didn't get all the details from him - what say you?

Generally speaking, the idea is to hone in on a COL the rifle likes *first*, then secondarily hone in on a velocity (powder charge) it likes, with a given bullet and powder combo you are trying, as follows:

Then shoot those groups to find the best group - this is the COL the gun likes. Stick with that and don't change barring something unusual.

Then and ONLY then does he mess with powder charges at that given COL.

If you do this, do you generally use 0.5 gr or 1.0 gr for your increment with "full power bottle necked cartridges"?

So the main thing to take away is that COL is more important than powder charge for accuracy - legitimate conclusion / method? Any better ones?

1. I don't think the COAL is the most important variable. I generally set the bullet as close to the lands as possible without actually touching them. If the rifle has generous free bore you won't be able to set the bullet near the lands. For magazine fed rifles, magazine length may be a limiting factor. For Barnes bullets, I crimp (one of the few bullets I routinely crimp) in an appropriate groove and COAL doesn't seem to make much difference. If a gun has a well aligned chamber, throat and barrel, COAL will make less of a difference. One of my rifles does very well with a variety of bullet weights, lengths and COAL.

2. For small bottle necked cartridges like the 223 Remington, 0.5 grain powder increments is prudent. For 308 Winchester up to 300 Winchester Magnum, I use 1 grain increments until reaching maximum (if that happens) at which point I use 0.5 grain increments. For bigger stuff like the 378 Weatherby Magnum, I still usually go with 1 grain increments but at the lower end of the load I don't think 2 grain increments would be wrong. Usually as the powder charge is increased, group size with tighten to a point at which time group size will start to widen again. I stop where group size is the tightest. I never use a chronograph to determine if a load is safe and I know the bullet will be going fast enough.

3. For initial load workup I shoot 3 shot groups. When a load looks promising, I will shoot more 3 shot groups or 5 shot groups to confirm my initial impression.

4. Specific powder can make a big difference in a given cartridge. The Nosler manual shows which powder gave the best accuracy and I usually try that recommendation first.