WTH

[chad]

So I went today and shot the 280AI again. a month ago I shot it and put three bullets in the same hole at 100yds. Today I went with the same load and got 1" to 1 1/4 at best. H4831 powder and 140 grain ttsx bullets. I cant see what went wrong.

temperature was hotter today but I had my loads in a cooler with ice. I thought H4831 was temp stable?

Really frustrating.

 

[MudRunner2005]

I had this same thing happen with H1000 in several different calibers. Since removing it from my lineup, I haven't had any issues since. But I also haven't been to the range in quite a while since the temp has really warmed up, with my 7828 SSC loads. I need to go soon.

 

[FearNoWind]

Look first to the shooter, then to the other factors like rest, wind, etc. before focusing on the load and its components. When things go wrong unexpectedly it usually isn't the load.

 

[Mikecr]

Your powder may or may not be temp stable, but this is still relative to your system.
That is, your gun(combined components) or the load(combined components) might not be stable at all.

Why cool the ammo? Is this 'cold weather' ammo or something?
Here, you have a hot gun with cold ammo, and I can't picture matching this in the field.

If this is actually temp related, it represents what I counter with months of cold bore load development(lotta work). You may have a case, as I have in the past, where you get best accuracy or precision (not both).

Precision is pulling out a gun and putting multi-shots in a tight group -wherever they happen to fall.
Accuracy is pulling out a gun and putting 1 or more -where you need it.
I can tell you accuracy is the more challenging attribute. It is also the most important attribute for a LR hunting gun, and it's sometimes independent of precision.
If this is a hunting gun, keep your eye on it's accuracy separate of grouping, so that you don't go past an accurate load for one that groups better.

 

[chad]

This is a hunting gun. I hunt from 60 deg to 20 deg.

 

[Canadian Bushman]

Precision is pulling out a gun and putting multi-shots in a tight group -wherever they happen to fall.
Accuracy is pulling out a gun and putting 1 or more -where you need it.
I can tell you accuracy is the more challenging attribute. It is also the most important attribute for a LR hunting gun, and it's sometimes independent of precision.
If this is a hunting gun, keep your eye on it's accuracy separate of grouping, so that you don't go past an accurate load for one that groups better.

Im guilty of pursuing groups, it ends up in wasted money, time, barrel wear, and a gun that rarely puts a bullet where you want. It will also really shake your confidence.

 

[FearNoWind]

Precision is ... putting multi-shots in a tight group -wherever they happen to fall.
Accuracy is ... putting 1 or more -where you need it.
... accuracy is the more challenging attribute. It is also the most important attribute for a LR hunting gun, and it's sometimes independent of precision.

That ought to be printed on every hunting license in the country.

 

[Lefty7mmstw]

Precision is pulling out a gun and putting multi-shots in a tight group -wherever they happen to fall.
Accuracy is pulling out a gun and putting 1 or more -where you need it.
I can tell you accuracy is the more challenging attribute. It is also the most important attribute for a LR hunting gun, and it's sometimes independent of precision.
If this is a hunting gun, keep your eye on it's accuracy separate of grouping, so that you don't go past an accurate load for one that groups better.

Mike hits the nail on the head with the accuracy/ precision lines...
I personally won't field a bullet/ powder combo unless it's been tested on multiple days in varying field conditions. I've seen many loads go to crap with most of the better powders out there just because something isn't right for my rifle. I just had to yank down a box of 150 ablr ammo for the 7stw the other day for that reason; last fall, it was 1/2 moa ammo. Let it go until this year and it's having a hard time with 1.5 moa. Different conditions... same rifle and ammo. If I can stay sub moa in all conditions I test in, the load is good for me and I'll load a couple of hundred.

That isn't to say I've run every load I have loaded on the shelf through that regimen. I won't, however, use a non/not fully- tested load on anything living. I've made the mistake of going out with a mediocre load a couple of times and no more. I've got enough rifles that I can prove the load before I field it.

 

[chad]

We'll I know I won't be hunting in 90 + degree weather. But I'll wait till I can go shoot it in the early morning when it's cool or wait till it cools down all together to see where it's shooting. No way would I hunt with it the way it's shooting now. I want to know where my bullets are going.

 

[Lefty7mmstw]

We'll I know I won't be hunting in 90 + degree weather. But I'll wait till I can go shoot it in the early morning when it's cool or wait till it cools down all together to see where it's shooting. No way would I hunt with it the way it's shooting now. I want to know where my bullets are going.

Got any rl19?? My brother has been running it with 140's in his 280's for years and in multiple rifles it has performed in all conditions. I'm a bit surprised that h4831 has gone to pot for you for this load, but I've seen it with many combo's before.

One other thing, have you double checked your gear to make sure something hasn't loosened up or otherwise acted up?

 

[chad]

I do, I used it when it was just a 280 and it shot awesome but it was worse for temp swings.

 

[Mikecr]

The test of time is an agonizing part of load development..

You've improved the cartridge and that tells me you've probably had some work done with this gun.
You believed the powder would make it stable, so you've probably looked into other possibles -with the gun. So I assume you've ruled out the gun & scope. But let's consider the probability that the powder itself is NOT doing this to you. There is no reason to think it's 'bad' powder, right?
This leaves unstable load.

You could take another crack at load development. Keep a diary, log everything.
I would start with Berger's seating depth testing, right where you're at, with no other change for now.
Get really serious with distance to lands(DTL) consistency, every one verified.
You might recover right here.

 

[elkaholic]

This could be something as simple as some serious mirage. I have had this happen several times with loads that I KNOW shoot very well and yet the groups, on a given day, go south.......Rich

 

[chad]

I use the hornady bullet comparator. I check every reload. There all where they need to be. I'm suspecting a 30 deg in temp day, and the sun beating on my barrel. If that don't explain it I'm gonna blame the guys next to me. I'm at a loss. Give it another day and it's possible it is just me and my shooting. In to much of a hurry or something.