Load Development?

[scdogman]

In Using the same gun and powder, do you find that different bullets of the same weight will have similar nodes.

The 162 eldx and 160 accubond both had the same two nodes. I found accubond easiesr to find the nodes. I was wondering if I could use easier to tune bullets to load to find the nodes and look for the nodes with more PITA to tune bullets.

The eldx is a longer bullet.

The GMX is a longer bullet as well. I want use the SST to hunt for the nodes. The GMX was the 1st bullets I have loaded. I want to reverify my loads though. Its good out to 500 yrds but I want to be sure I'm dead on it.

 

[Greyfox]

I find that there is no common theme and it depends on the specific rifle/chamber. Sometimes yes, sometimes no. But I will generally try the same seating depth that I got good results with when testing subsequent bullets of similar shape.

 

[scdogman]

I'm trying to do OCW development. In doing so I'm shooting all at suggested coal until I find the powder charge. I'm adjusting the seating after I find the powder node.

 

[Mikecr]

OCW is purely about finding a forgiving powder load, while leaving seating in disparity.
But I care more about best seating than best powder load, as seating is the biggest (coarse) adjustment to results.
So if I were to change bullets from those load developed with, I would keep the same powder load, and the same CBTO to begin. Then tweak seating to shape the grouping. If that doesn't get it back, start over completely, beginning with full seating testing, and ladder testing with powder.

 

[scdogman]

I believe after you find the powder charge, Seating depth can be found using ocw methods also.

I'm curious about others. You guys weigh more to seating depth than charge weight. I'm new to this. I just thought it was interesting that both bullets had the same charge weight at two nodes. They were shot months apart. The seating depth is different for both bullets.

 

[scdogman]

Thanks for the replies!!!!

 

[TOM H]

I believe after you find the powder charge, Seating depth can be found using ocw methods also.

I'm curious about others. You guys weigh more to seating depth than charge weight. I'm new to this. I just thought it was interesting that both bullets had the same charge weight at two nodes. They were shot months apart. The seating depth is different for both bullets.

Last I adjust is seating depth and I did find little difference between 160AB and 162gr ELD-X in my 284 and that was done 300yds and I am shooting same load. The 160gr AB been my hunting bullet. I haven't had chance to shoot it longer yardage and as cold been here Co may not get that done till early spring.

Till I do more shooting I'll just wait and see. I spend little more time shooting 200gr ELD-X 200gr in one of my 30-338mag.

 

[Mikecr]

I believe after you find the powder charge, Seating depth can be found using ocw methods also.

No, you can't find best seating with powder, nor without doing full seating testing.
It sounds like you've decided that seating is a fine adjustment, which means, like most, you've never done full seating testing.

You already know powder won't change much between the bullets. You should know best seating can change. So you should consider this as possibly needing tested (actual testing by itself).

 

[scdogman]

Mikecr. Not sure what you are trying to say or maybe I wasn't clear.

I said after you have found your desired charge weight, you can run a new set of test to find the best seating. In doing this only one variable is changed at a time. Heck I'm new, but I'm sure the guy that came up with the OCW method stated that.

Basically shooting round robin groups varying the seating depths.

 

[Mikecr]

I'm talking about full seating testing (aka Berger recommended).
Keep in mind that OCW is not about producing a most accurate load(it won't). It's about finding a most forgiving load. With this, seating is not credibly considered as it really contributes nothing to that endeavor.
Basically, they have you pull some seating out of your butt for OCW testing, then try to half *** address seating later. Accuracy-wise, this might work, or it might fail, as it really has horses pushing the cart instead of pulling. If you were to run full seating testing -with an OCW load, it better be a wide node or your seating testing will collapse OCW at the same time (2 changes at once).

I'm suggesting you can have both forgiving and best accuracy -from OCW (still not the most accurate) by tweaking your method here.
Do full seating testing before doing OCW, and you'll then be running OCW with best seating. Then after completing OCW, tweak seating as they have you (a tiny window of adjustment) to best shape your OCW grouping.

A Ladder shot while in best seating leads to the most accurate load(but not most forgiving).

 

[Wachsmann]

Here is something I have found out through personal trial and error. The Berger method works for just about any bullet/rifle combo (just about). For me I have started with a middle of book range charge and seated from the lands moving every .020 back. I generally shoot 3 to 4 rounds at a time at 200 yards. At some point one the group will tighten up and then spread back out. Next step take the best group and move up in powder and seat the same group 3 to 4 bullets each and then 2 or maybe 3 other groups that is .010 and .005+/- off the group that shot the best. You could also do the second test by increasing the powder change in each group of 3 bullets and see if you get one length that is stacking on top of each other. I think this is the round robin method but it seem to provide the least amount of bullet down the barrel for a accurate load and when I've done it this way I shoot at minimum 300 yards.

Don't take this as anyone trying to tell you your doing it wrong, just trying to save you some barrel life and expense in the long run.

I had a 257 Weatherby that I was trying to do the same as you are doing. Powder charge first. After about what was probably 100 rounds down the pipe I finally found a load, seating depth combo that worked good. The last kicker was neck tension. The gun always would shoot factory ammo better than what I loaded. Finally the light turned on and I noticed the crimp on the factory cases and I'll say it was one hell of a crimp that Weatherby puts on they cases. I pulled one bullet apart and the bullet was actually deformed quit a bit from the crimp. I got a bushing die and a couple of different bushing and was able to get the load shooting better than the factory loads just never as fast.

 

[RockyMtnMT]

Here is something I have found out through personal trial and error. The Berger method works for just about any bullet/rifle combo (just about). For me I have started with a middle of book range charge and seated from the lands moving every .020 back. I generally shoot 3 to 4 rounds at a time at 200 yards. At some point one the group will tighten up and then spread back out. Next step take the best group and move up in powder and seat the same group 3 to 4 bullets each and then 2 or maybe 3 other groups that is .010 and .005+/- off the group that shot the best. You could also do the second test by increasing the powder change in each group of 3 bullets and see if you get one length that is stacking on top of each other. I think this is the round robin method but it seem to provide the least amount of bullet down the barrel for a accurate load and when I've done it this way I shoot at minimum 300 yards.

Don't take this as anyone trying to tell you your doing it wrong, just trying to save you some barrel life and expense in the long run.

I had a 257 Weatherby that I was trying to do the same as you are doing. Powder charge first. After about what was probably 100 rounds down the pipe I finally found a load, seating depth combo that worked good. The last kicker was neck tension. The gun always would shoot factory ammo better than what I loaded. Finally the light turned on and I noticed the crimp on the factory cases and I'll say it was one hell of a crimp that Weatherby puts on they cases. I pulled one bullet apart and the bullet was actually deformed quit a bit from the crimp. I got a bushing die and a couple of different bushing and was able to get the load shooting better than the factory loads just never as fast.

Interesting thoughts on the crimp. Crimping has kind of disappeared over the years. Used to be standard practice. We are starting to crimp more and more on our loading because there is very little neck tension on our bullets because there is very little baring surface contact. But in general seeing good results. Certainly no down side to it.

Would like to hear others opinions on the crimp.

Steve

 

[scdogman]

So how many rounds on average is it taking everyone to develop a consistent under MOA load? Or how many rounds should it take?

 

[Mikecr]

Keep in mind that higher tension/grip means higher variance of it.
I'd go with a faster powder before a crimping bullet grip.

Barring problems, a bolt action should break MOA from the git-go.
For 1/2moa and better, starting from scratch, it takes me ~250 shots including seating testing during fire forming of 50 cases, a ladder test, incremental load development at ladder potential, and final seating tweak to define window and center. This gets me to precision that is hopefully good enough. If not, I'll have to identify the reason, and likely go back to ladder testing after resolution.
For accuracy, I then roll into cold bore load development and ballistic validations, which takes a good while. This is where cut rifled barrels pay off, and all my future barrels will be melonite treated.