Should load development methods always yield results?

[Pond, James Pond]

I've been way more methodical and precise with my .308 loads than I have with my pistol loads. As such I have been using the Newberry OCW method. My shooting is a weak point in this and I expect that a good shooter would have got more from the process. It did work though and gave me what looked like a good load for an A-Max bullet recipe.

However, I got really inconclusive results with a Lapua Scenar bullet of the same weight. By the end I could not say which was the best charge weight to single out.

Recently, in another thread about 1000 yd shooting, a link was posted to a breakdown of other methods such as the Audette ladder. I have not sifted through the details yet, but I plan to.

My question is could a certain bullet/powder/case/primer combo be easier to read and tune with one method, yet be really inconclusive with another?

My guess is no, as I image any given development method would include which ever load would end up being the ideal load for my rifle. After all, 40.7gr of N135 in the OCW method is 40.7gr in the Ladder method, isn't it?

So tell me, if one sheds no light might another work in its stead?

[AllenJ]

My guess would be "no" also, unless one of the methods was somehow flawed.

[pathdoc]

My question is could a certain bullet/powder/case/primer combo be easier to read and tune with one method, yet be really inconclusive with another?

Remember that the methods are looking for different things. The ladder test seeks a plateau of charge weight range within which vertical dispersion is minimised and carrying out the test pays no heed to horizontal dispersion at all; shifting winds during the shoot aren't a problem, so long as your bullets stay on the target and you can track which ones are hitting where & in what order.

The OCW method seeks a plateau of charge weight range that minimises the shift of group centre, and controlling variations in both vertical and horizontal dispersion during the test is potentially everything; markedly shifting winds or anything else that interferes with horizontal dispersion without you knowing what it is or being able to correct for it could screw you right up.

Neither method actually looks at the tightness of group size. Those who shoot events that are purely for group without caring exactly where on the paper that group clusters, and who are prepared to take their time weighing every charge to closer than a tenth-grain accuracy, may potentially not be served by either method!

[std7mag]

That said, you have to remember that serious competition shooters may go through several barrels in a year.

Sierra recommends finding the powder charge first.
Then seating bullets to different distances away from the lands, to find the sweet spot of the bullet for group size.

Scenar's seem to work best with heavy for caliber weights, and can go from touching the lands, to quite a bit off of the lands. You just have to experiment with it.

[Wreck-n-Crew]

I've been way more methodical and precise with my .308 loads than I have with my pistol loads.

I am not sure what precise means for your pistol loads but there is a lot to be gained from getting the load fine tuned in them as well. I have found that acuracy and cleanliness of powder due to good burn are always a plus. YMMV

On another note I admire your thirst for knowledge and lack of fear to ask for opinions. You seek more than some and I believe it will serve you well. I wish more people would set aside pride in everday life and open up to learning. Goes back to a lesson that my dad taught me as a kid (that I am still learning) " Son keep your mouth shut more and your eyes and ears open, you will learn more!" Relly helps more when you have so many people so willing to share knowledge and experience too! Set me straight a time or two for sure.

PS thanks TFL.

[hooligan1]

Taylorce1 has a cool, fast, and cheaper method in my opinion, he loads six cartridges with a medium powder charge at test "jump". At .030, .040,.050,.090,.130, off lands,and when he gets promising group, he then adds more powder for velocity until group opens. Now I only load 3 rounds a group so I save a.little more powder and bullets, and it has proven to me to be faster then OCW test. I have found loads for my rifles with as little as six rounds fired total, then maybe add more powder for velocity.
It works dude try it.

[Pond, James Pond]

I wish more people would set aside pride in everday life and open up to learning.

Pride?! What is this "pride" of which you speak?

Well, pretending to know stuff just looks too much like hard work and most people can't act well enough to pull it off, so I just ask!

Pistol rounds. I am lucky in that VV powders are very clean. For pistol rounds, I load 3-6 rounds of 0.2gr load increments from about mid charge all the way to max. I then play with crimp. My primary goal is a clean, complete, healthy burn.

Beyond that my goal is velocity range (often based on the bullet weight) and finally group size. Given that I shoot from 5-25 yards, as long as they land comfortably in alpha zone, I am happy.

[hartcreek]

How much rifle shooting have you done and was it organized? It could well be that you are doing something wrong posture wise or with your breathing.

I just got back into shooting my 30-06 and I am working up a new load because I can no longer find 4831 instead I am using H 414 which is not like spegetti and sure has a different burn so with having to sight in my rifle and a new load using my own hard cast bullet I am having to relearn my body to be accurate but I can do that as I had adiquate training through the CMP but if you havent had something similar you need to or ar least some coaching.

The more rounds that I have put down range have gotten me back to being accustomed to my 30-06's recoil so as soon as my broken case extractor comes in I can get her fine tuned.

[Pond, James Pond]

It could well be that you are doing something wrong posture wise or with your breathing.

I am self taught and self-teaching with only TFL and what seem like informed YouTube videos as my only instructors so I think we can be pretty sure that I am making all number of technique mistakes. I try to apply the breathing and posture techniques I've been told about...

I also practice with .22 when I can.

[tobnpr]

I hate load development...really...

I know it's a necessary evil, but damn, it never seems to end in pursuit of the perfect round- I just want to get it over with and get on with the shooting!

That said, I use OCW, mainly because the range closest to me is only 100 yards (they have a 200 M but it's only open one day per month due to lack of interest). The 1000 yard range is nearly a two hour drive each way so we tend to do more real shooting when we go there.

I do plan to try longer range paper aka the ladder method next time when I can stretch it out to 400-500 yards.

I've not seen it discussed much before- but what OCW at 100 yards does not account for is SD in bullet velocity. You can have a huge spread in velocity from a load that prints very well at 100- but stretch it out and the vertical becomes a real liability. I think this, at least some of the time, is why OCW developed loads may not perform as well at long range- and why I always try to have a chrono under the bullets as well.

[pathdoc]

I suspect the ideal would be a ladder to find a good plateau for minimising the vertical distribution and then an OCW run at narrower charge intervals within that range. I know not everyone can do that, but it would be interesting to see if such an approach worked 'better' than either separately.

[Jimro]

It is my eperience that some powder/bullet/brass/primer combinations will never come together for some rifles, no matter the method used.

Jimro

[pathdoc]

I almost said that earlier, but the issue at hand was the methodology.

[Unclenick]

James,

Your thread is felicitous, as just two days ago I came across an answer to a thread of yours from last year that I somehow failed to post. It happens to be a good example of how you might get an ambiguous result.

In that thread you were developing loads for the .308 and had provided locations for a round robin of holes from the rifle and, IIRC, I had mentioned that I spotted a problem in the data. That problem was that the first shot in every set of three appeared to be highest and to the left, while the last shot in every three but one was lowest and to the right.

The first plot below is the mean 3-shot group center and a running average of 3 (9 shot groups) in yellow. It clearly shows the same thing an Audette Ladder would show, which is clustering at an harmonic point at 40.55 grains powder charge that doesn't change appreciably for another 0.45 grains in either direction. So you could load to 40.5 grains or 40.6 grains or let the scale dither inbetween and be at a best load. The drop in location of the last set of three, while not conclusive, suggests that another two or three 0.3 grain steps, if advisable from a pressure standpoint, might have got you still another sweet spot, but it is also may show you are at the end of the gun's range, so it wouldn't actually like that. You'd know from other pressure signs.

The next two plots, however, show every individual shot for each charge weight (I labeled the first and last three of each), one for horizontal and one for vertical location. The dashed lines are connecting the first and last shots. Note that they don't cross in either plane. This is strongly suggestive of heat walking as the session continues. This may mean you need to float the barrel because of a barrel contact point shifting pressure with temperature. It may mean you need the barrel pulled and the action trued to get the action threads and front of the receiver square for the barrel shoulder. It may mean the barrel was not stress relieved before contouring, in which case it might benefit from being pulled, stress relieved, straightened afterward (if necessary) and refinishing (stress relieving needs about 1000-1100°F (535-595°C), depending on the steel, so it whacks the finish and needs a non-oxidizing atmosphere oven, so it's probably the most expensive thing to try). Magnetostriction can also relieve stress without harming the finish if you can find someone with the equipment to do it. Cryo treatment is repeatedly reported to improve heat walking, but I don't know how consistently that's true. It's probably the least expensive thing to try here, but I don't know about where you are.







Anyway, you can see how, despite being in a load sweet spot from a harmonic standpoint, the drift keeps the shots from clustering tightly, and that's the example of disguising a sweet spot this sets.

[Pond, James Pond]

This is strongly suggestive of heat walking as the session continues.

Please tell me it could also just be my shooting!

In all seriousness, I remember the thread and appreciate the input: I would never have know how to begin putting all that data together. As for the possible solutions, is there a way to check barrel rise?

A rifle clamp or something else to remove me from the equation?

The truth is that I am almost certain that all the possible solutions mentioned, except perhaps the barrel truing part, would be impossible to find here in Estonia. And if they weren't, a new rifle would almost certainly be the cheaper option. The barrel should be floating as there used to be a contact point when cold, and I sanded the stock away until paper would slide through freely. Perhaps the gap is such that a hotter barrel reconnects.

I will maybe load up some more of the 40.55gr sweetspot and see if I can get a good group. In reality, I still only have bout 200rds of .308 shot, ever and I do tend to have a flinch if I don't concentrate very hard.

[Jimro]

When testing for accuracy, sandbags are your friend. A sandbag or two under the forearm, and a sandbag folded up between your shoulder and the butt, with another sandbag under the buttstock.

This isn't as good as a "lead sled" but can be pretty close in terms of letting the rifle recoil consistently without killing your shoulder trying a free recoil method.

If you find a load that groups tight from the sandbags, and things open up when you shoot from a field position, odds are it is you being inconsistent breaking the shot. Have a friend load your magazine with a dummy round at random, if you are flinching it will show up very quickly.

Another thing to do is practice 3 to 5 perfect dry fires between actual fires.

Jimro

[Unclenick]

James,

Sure, it could be your shooting. The regularity of the drift in the plots, though, makes that seem unlikely to be the whole story. However, it's not impossible for gradual position fatigue to cause that kind of drift. And checking out the other factors isn't that hard. It just consumes time, effort, and ammunition.

As to the shooting itself, check out this article and note the practice techniques. Having a snap cap for dry firing is critical. Practicing hold and trigger control in the dark is very effective at developing your kinesthetic sense of position and straightness of pressure back on the trigger. When the lights are on, practice dry firing while sighting on something small and not letting your eyes blink so you can see the slightest perturbation of the point of aim when the firing pin slams forward. You want none. Keeping working for none. That's shooting's most important skill. Perfect hold is secondary to it. This is the single thing bad shots almost universally are found to have got backwards. Undisturbed sight picture is number one, and training positions fine tunes you from there.

Follow the classical advice to let the exact moment the shot breaks be a surprise. The reason is not just as way of avoiding yanking the trigger. The human brain, short of developed task-specific muscle memory, generally needs a quarter of a second or so to start reacting to something, recoil included, though some individuals can cut that time roughly in half with muscle memory training. By having the shot break by surprise, you are guaranteed that much time before your muscles start trying to control the gun and push the muzzle off axis. Even with a very slow lock time, a gun has a bullet out of the muzzle in a quarter of that time or less. So breaking the shot by surprise gives you at least that reaction time as the follow-through period needed to avoid perturbing the sight picture before the bullet starts moving.

Position helps. A tight hold fatigues muscles and is harder to maintain. This can cause gradual creep in POI. Try for a relaxed hold that works for you off sandbags, as Jimro suggests. If the relaxed hold makes a long shooting session difficult, get a shoulder recoil pad.

If you are having bedding or other issues, resting the front end of the stock on bench bags can be a source of irregular recoil moments. Put some polyethylene sheet over the bag and rest the magazine floor plate on it instead to see if that helps. Some guns group much tighter this way.

To check for a change in stock contact with heating, you want the stock sanded down enough to let at least a piece of paper money (and some prefer a business card for extra margin of assurance), slip between the stock and bore. Just keep retesting that as the gun warms up. If you stop being able to move the paper all the way down the barrel channel in the stock, then contact is being made.

Were the loads from last year fired before or after you sanded the stock? If before, the sweet spot load may have changed. A stock contact point changes the null point in the barrel's harmonic swing. Some make contact on purpose for that reason. Indeed, there is an adjustable contact point system that tunes your rifle to a particular load.

To check for heat walking, clean the rifle and be sure it's cool. Set up ten small target centers. Print them onto typing size paper four to a sheet with cut lines, then cut them before or after shooting, as you prefer. Assuming last year's load was developed after sanding the stock and the stock isn't failing to pass the contact test as it heats, fire one round of that 40.55 grain (2.63 gram) load into each of the ten centers. I prefer to move left to right rather than up or down, but whichever tendency your setup prefers, use that. Don't give the rifle time to cool between shots, but don't race. A 30 second pace is good, as you want the heat to have time to spread in the gun between shots, but not enough to dissipate significantly. To minimize the effect of heat on the ammunition, let the bolt stay closed on a fired case and through most of that time between shots, then chamber and shoot the next round in five or ten seconds.

When you have the ten centers, line them up carefully on the floor, then stretch a string across the targets so it cuts through what your eyeball says is the average center. Repeat with the targets vertically stacked. The horizontal and vertical stacking cause the string to bisect vertical and horizontal displacement respectively. If the strings are horizontal and vertical, respectively, you don't have heat drift. If they are angled in a clear trend, you do.

If you want a more exact approach, you can measure each hole location as before and let Excel draw the lines then apply a least squares fit linear trendline and give you a measure of the correlation (R²). I've made an Excel file for this. Just enter your actual information in the blue background cells. The sample numbers I put in there now show a pretty distinct vertical drift with no significant horizontal drift.

[T. O'Heir]

"...Please tell me it could also just be my shooting!..." Ok, but you need to get the load worked up too. Use one method and stick to it. Trying 'em all doesn't help, mean or tell you much.
And floating the barrel guarantees nothing. It is not a magic, um, bullet. Not all rifles like a floated barrel. Anyway, consistency is what you're after. Your rifle may just not shoot well enough for 1,000 yard shooting.
Not a fan of ladders or OCD, I mean, OCW myself. I load a mag load or 5 beginning with the starting load and work up by half a grain to the max then go shoot off a solid bench. Looking for the best group at 100 yards only. That's very much simplified, but it tells you if the rifle likes the load or not.
Have you shot the rifle with good factory ammo? Gives you a reference point.

[Pond, James Pond]

3 posts and lots of info to digest!!

Were the loads from last year fired before or after you sanded the stock?

Before, I sanded the stock as soon as I bought the gun. I remember paper would not pass before, but did after sanding, but it was still tightish, so perhaps a bit of barrel expansion makes it connect.

I like the multiple target technique for barrel walking!!

As a point of interest, I presently shoot with a bipod, attached to the front sling mount. That is pretty much right where the tight stock-to-receiver tight spot was.

Have you shot the rifle with good factory ammo?

I used to shoot Norma Jatkmatch 155gr FMJ training ammo. I bought it as it was the cheapest (FMJ not being allowed for hunting) and the cases were good quality for subsequent reloading. I haven't shot it for a while and seeing as my shooting is pretty bad now, I can assure it was worse then, so I'd have to buy some more and see what happens to the pattern.

Your rifle may just not shoot well enough for 1,000 yard shooting.

Heresy!! HERESY!!
(although, that could just as easily be heresay, heresay.... )

[HiBC]

My 2 cents:A lot of match shooters have put several lifetimes of work into developing accurate .308 loads.
Some are 4064,some are 4895,some are Varget,some are RE 15,and some are your Norma powders.

Look at what match shooters use as a standard load.There are loads "If the rifle won't shoot well with this load,the rifle won't shoot"

If your rifle will shoot 1MOA (or whatever,2 MOA?) average,or close,with 2 or 3 of those standard match loads,for the sake of argument,all the time you put into improving your hardware,including ammo,will yield small rewards.
Like,if you are shooting a 168 gr MK with 44 gr + or - Varget,you trimmed your brass square,chamfered your cases,,and loaded it concentric,...maybe manipulating all the variables,or trying 4064 or RE15 or N140,you will gain .375 MOA.OK,thats nice.

It took how many load sessions and trips to the range?

Now,what if you loaded 500 rds of a load that proved "pretty darn good"

Then you went to the range and shot 50 good,careful shots ten different sessions...prone,sitting,etc.I bet you will realize more benefit working on the software....you!

Do enough testing to find "a pretty good load" then shoot!

You have to be a pretty world class shot to take advantage of the last degrees of ammunition accuracy.

And,FWIW,yes,the old slide the bill of currency between the barrel and forend will show an obvious tight spot.Time honored tradition!But,imo,during the dynamics of firing,.05 or .1 mm is not enough.Your barrel will dance more than that,and likely bounce off something.I like a minimum of .5 mm,and .8 mm clearance is better...especially if you will use a sling.

[Snyper]

It's easy to overthink all this.

Just keep trying different loads, and take good notes of what works, and you'll find the loads that your gun likes

During that process, you'll also become a better shooter