Same EXACT load as last years load shoots like crap

[gohring3006]

Pull the bullets and powder from last fall and load your stuff in that brass. Then load the bullets in your brass your currently loading, then use the powder from last fall. Start a process of elimination until you find the culprit.

 

[Joefrazell]

That would be a reasonable thing to check except the old (but same exact) load shoots a tight group from the same rifle and the same rest under the same conditions. The rifle was cleaned this winter and not shot since until now. All the normal things to check, such as action screws, fouling, hot barrel, etc are without relevance when last-year's load shoots ok between groups of the exact same recent load. In fact, I shot a good group from last-year's batch in a hot barrel.

Something changed in the load as it's not possible for it to be the exact same and have two different results. Is the new load the same jug of powder? Same lot of primers? Something is different. Or the old load just happened to shoot well but will it repeat several times? It's very strange and I hope you get it figured out.

 

[Beluebow]

This exact same load shoot 5" groups, all over the place.

From 1moa to 5moa is something mechanical not a reloading issue IMO....Unless the barrel just took a crap.

 

[Joefrazell]

From 1moa to 5moa is something mechanical not a reloading issue IMO....Unless the barrel just took a crap.

Good point. But he does say the old load still shoots tight. I think he needs to be completely certain of that before he gets too far into chasing around his tail messing with ammo. I'd go shoot it again with old ammo and just make sure he didn't get a few decent groups by fluke.

 

[lancetkenyon]

Have you chronographed both loads? Old and new? Temps will make a difference in velocity, but with last year's ammo shooting better than this year's, you need to verify speeds between the two.

There has to be something different.
One thing different, could be that ammo built last year had a bit more neck hold due to a very slight bullet weld to the case neck. But, if last year, you shot your ammo fairly soon after loading, that should not be it.

Verify primers are the same
Verify primer seating is the same
Pull apart a loaded round from last year and reweigh the powder charge. Scale might have drifted, so this year's loads are a bit different.
Try a new bottle of powder and see if that changes anything
Neck tension
Check headspace from last years loaded ammo to this new batch
Verify seating depth (CBTO) is the same between last year's and this year's ammo. Maybe your die got adjusted or bumped inadvertently

 

[HaroldNRAEndowment]

Are you using the same processed brass as you were using?
Same box of bullets and primers?
Has the powder bottle been tightly sealed since you loaded up last September load?

I've been chasing my tail on a 22-250 load. I don't have it totally figured out yet but one thing I learned is the last bit of powder in the bottle that has been used over the last year will give a higher velocity than a fresh, sealed, bottle with the same lot number. Like 80 fps for this 22-250.

This is a thought without any proof. If you have ever taken a pan or bucket of mixed sand, pea gravel and stones that are mixed well and start to shake or vibrate the pan/bucket, the larger sizes will migrate to the top due to more space between the larger pieces, and the smaller pieces migrate down by sifting between the gaps of the larger pieces. Is it possible that powder in a canister can fracture into smaller pieces and migrate to the bottom of the canister? The shape is a major player in speed of progressive ignition.

 

[baldhunter]

I find most of the accuracy issues I encounter other than ammo is usually related to the stock.If your having issues with getting the accuracy your looking for, change the stock and see what happens.I had a rifle that seemed to be in good shape.The factory stock was original,but the rifle would group around 2-3".I switched it to another stock I had bedded.I shot three in the same hole and two was just barely outside making the five shot group just under one half inch.Here are before and after with nothing more than changing the stock.

 

[Les in Wyoming]

Are you using the same processed brass as you were using?
Same box of bullets and primers?
Has the powder bottle been tightly sealed since you loaded up last September load?

I've been chasing my tail on a 22-250 load. I don't have it totally figured out yet but one thing I learned is the last bit of powder in the bottle that has been used over the last year will give a higher velocity than a fresh, sealed, bottle with the same lot number. Like 80 fps for this 22-250.

Same exact brass. In fact, reloaded some of those that shot well with same exact load. Powder is half-full can sitting on shelf.

 

[Rflshootr]

Just a thought....do you have both IMR and H 4350 and maybe grabbed the wrong one?

 

[Veteran]

Its something mechanical.
Scope, Stock and harmonics,
or fouled or worn bbl. or some difference in harmonics from shooting prone w tripod vs. bench or something like that.

1 MOA to 5 MOA is not a slight charge weight, or primer, or brass issue.

 

[Tatergunner]

I may have missed how you made the changeover in powder and bullet. Your target picture notations indicate A4350 and 150 gr projectiles, and your original post states IMR 4350 and 168 Grain projectiles. Are you comparing apples and oranges?

 

[gyantgunz]

I'm thinking possibly moisture somehow got in the can of powder. Maybe try throwing some desiccants in the powder ?

 

[whitetailjunkee]

Based on what I'm hearing and what you've done so far, I would start with your scope. I have had a similar situation twice, and both times it was the scope. Crosshairs we're messed up in one scenario and I remounted the scope in the second scenario. The first scenario I mounted a second scope and it shot normal so I sent the scope in to Leupold and they told me there was an issue with the cross hairs. When I got the scope back from Leupold, the problem was fixed. I was shooting 3-5 inch groups before it went in to Leupold; then back to sub MOA afterward like it did originally. In the second scenario, I never narrowed it down to exactly what was wrong but after remounting the scope, the gun returned to shooting well so I assume something was loose. These were two different rifles about 10 years apart but both went from shooting sub MOA to unpredictable shot patterns; both were related to the scope and or how it was mounted. Good luck.

 

[jpfrog]

Based on what I'm hearing and what you've done so far, I would start with your scope. I have had a similar situation twice, and both times it was the scope. Crosshairs we're messed up in one scenario and I remounted the scope in the second scenario. The first scenario I mounted a second scope and it shot normal so I sent the scope in to Leupold and they told me there was an issue with the cross hairs. When I got the scope back from Leupold, the problem was fixed. I was shooting 3-5 inch groups before it went in to Leupold; then back to sub MOA afterward like it did originally. In the second scenario, I never narrowed it down to exactly what was wrong but after remounting the scope, the gun returned to shooting well so I assume something was loose. These were two different rifles about 10 years apart but both went from shooting sub MOA to unpredictable shot patterns; both were related to the scope and or how it was mounted. Good luck.

Its something mechanical.
Scope, Stock and harmonics,
or fouled or worn bbl. or some difference in harmonics from shooting prone w tripod vs. bench or something like that.

1 MOA to 5 MOA is not a slight charge weight, or primer, or brass issue.

I find most of the accuracy issues I encounter other than ammo is usually related to the stock.If your having issues with getting the accuracy your looking for, change the stock and see what happens.I had a rifle that seemed to be in good shape.The factory stock was original,but the rifle would group around 2-3".I switched it to another stock I had bedded.I shot three in the same hole and two was just barely outside making the five shot group just under one half inch.Here are before and after with nothing more than changing the stock.

Folks, these are good thoughts but the OP has already stated that the rifle shoots tight groups with the old load in between strings with the new loads. In other words, if the OP weren't shooting with new loads and only using the old loads, it would be shooting perfectly fine as-is. Mechanical was where my brain went first, but based on his process, I don't see it applying here.