Different brand cases - does it affect results?

[Paul]

Hi folks,

I am wondering at the impact different brands of cases may have on the accuracy, or more so the relative accuracy for a given load.

For example, what difference, and why, would my reloaded factory Hornady cases, be compared to Win Super X factory cases with the same load?

I know in my .308 there is a difference in ADI cases (seem slightly smaller due to thicker cases??) compared to Remington, though not sure what impact any of this may have on accuracy.

So in my 22-250, does a difference in case origin affect pressures, and hence velocity and hence relative accuracy or point of impact. Both maybe accurate in their own rights, but putting the same load in different may give different POI, and hence need re-sighting depending on the cases used, maybe?

Your thoughts are appreciated.

kind regards,

Paul

[LawrenceA]

It will affect things.
The big question is by how much.
First there is case capacity which will affect powder capacity and pressure,
Then there are differences in Flash hole size, length and placement, which may affect ignition consistency
Also neck tension and elasticity may affect pressures .
Even neck length may change particularly if it varies over the maximum for the chamber as this will create pressure spikes.

Think they are the main possibles.
All depends on your set up and your requirements.
Shooting barns at 25 yards it won't make a difference but a fly at a thousand???

[in2anity]

abso-f*****g-lutely. There's a reason comp shooters use Lapua and Norma brass, and that's simply because they are the most consistent. Largely in the form of consistent neck tension. You won't really see it unless you are reaching out there.

[Blr243]

I don’t know this myself but I just recently learned on another forum that internal volume from one brand of case to the next can vary significantly and with a warm load Ok in yourUsual cases Can cause dangerous Pressures if useing another case with different internal volume

[on_one_wheel]

All of the above.

I've batched my brass (all the same brand) by weight in batches of 50.
I couldn't be bothered measuring volumes so I figured that cases with less volume were likely to be heavier and vica versa. I found that my Winchester brass had weight inconsistencies... surprise surprise.
It definitely reduced my deviation from batch to batch and in turn, tightened groups.

[LawrenceA]

I don’t know this myself but I just recently learned on another forum that internal volume from one brand of case to the next can vary significantly and with a warm load Ok in yourUsual cases Can cause dangerous Pressures if useing another case with different internal volume

This is absolutely correct.
Can be a real issue if you are loading traditional cartridges as brass these days is much thicker than pre WW2.
Not a real issue for large cases but with the likes of 22 Hornet and the XX-20's it is an issue.

So basically you cannot readily use old published loading data in new cases due to volume shifts.

[Bello]

Hi mate
If you are seeking comp grade accuracy and consistency, in my experience ..yes, it will affect your group size for all the above already stated reasons.
But I have found in my rifles, when using these mixed cases out to about 200 meters, the minute of deer accuracy is good.
The comp shooters I have spoken to will use high quality brass like Lapua and Norma, they tell me this brass is more consistent in its weight and wall thickness.

I have also found, in my limited experiences with this issue, that as the caliber size went up, the inconsistency was less, bearing in mind my experiments were out to 200 meters only.

I use a lot of mixed brass in my 223, 243 and 308, as I am given heaps of it by people who do not reload, and for hunting I have not had any problems yet.
I always inspect the brass thats given to me first, any in perfections it's binned, then de-prime the brass wash it and then inspect for any issues.
My motto "If in doubt, throw it out"!!

I have had issues with Winchester brass before. It tends not to last as long as other brass I have reloaded for.
My 2c

[Bugman]

Not a target riffle shooter, but have switched to either Lapua or Norma for loading my 243.

[bigrich]

abso-f*****g-lutely. There's a reason comp shooters use Lapua and Norma brass, and that's simply because they are the most consistent. Largely in the form of consistent neck tension. You won't really see it unless you are reaching out there.

my 222 will shoot clover leafs or better with norma brass , with rem brass it always has a flyer that blows the group out to half inch . not that that's bad , but it is a triple deuce

the smaller the case , the greater the difference brass makes i've found . with my 358 win it's not fussy at all . new starline brass or ADI , PPU resized 308 brass, doesn't seem to matter . it's one of my most accurate rifles . not much of a shoulder on the case and i beleive the neck tension between brass brands is more consistant due to the bore size . at least that's my theory .....

[Oldbloke]

I suspect it really gets back to what you are trying to achieve. I'm sure what the blokes above said is correct. I'm in no position to say other wise.

But,, if only hunting/shooting up to say 200 yards, I'd suggest just maintaining brands in batches they will be OK. Accuracy will be acceptable.

[SCJ429]

Have you not got enough brass so you can sort them by headstamp? You can only shoot worse by mixing them up, there are enough variables without doing that.

[Ziege]

if all youre doing is shooting pests/hunting at average distances then no, my hunting rounds are all loaded the same regardless of brass manufacturer and there is a negligible difference. if you are wanting comp grade or long distance hunting rounds then it will matter.