Brass and accuracy

[Snowflakesmasher86]

A thought occured to recently (sometimes that happens) around the accuracy of a homeload depending on the make of brass.
I recently tested a thoery around brands known for good brass (in this case sako) vs other brands. I loaded up different makes of brass, but with the same load data in .243. I noticed quite significant group sizes between each group.

The one make of brass that i noticed was not as good groups was hornady. All brass was twice fired. Not annealed and fl sized and trimmes to the same length.

What have your experences been?

 

[Greenmist]

Winchester I find brittle, Hornady won't take certain primers, Remington and Sako I find vary between batches. Carefully prepped and sorted PPU is what I currently use and I'm quite happy with it, certainly accepts being stretched to other calibers, in my case .270 to .280AI

 

[Outback]

One thing to consider is the different case volumes with the same charge weight altering pressure .

 

[CookM]

Winchester I find brittle, Hornady won't take certain primers, Remington and Sako I find vary between batches. Carefully prepped and sorted PPU is what I currently use and I'm quite happy with it, certainly accepts being stretched to other calibers, in my case .270 to .280AI

I swear by PPU brass,l do have Federal ,and several other brands of factory brass.
But l my go to if new is PPU.
Across three calibres.

 

[Jagged77]

I’ve always used Lapua brass but have access to as much once fired Federal .308 factory once fired as I want. In an effort to standardise .308 loads across a few rifles I started using it and got some pretty good results - 1/4” groups and very low velocity variations. All the brass was annealed before F/L sizing. The last batch I reloaded however wasn’t annealed and whilst accuracy is still suberb I’m getting horrid velocity variations. Could be case volume or case neck tension or a combination of both. I’ll anneal the next batch and see what happens.

 

[Greenmist]

I swear by PPU brass,l do have Federal ,and several other brands of factory brass.
But l my go to if new is PPU.
Across three calibres.

I use it in .22-250, .300blk (made from .223) .280AI (made from .270), .44mag and now developing a .308 load, if they made .17rem which I'm sure they did, I'd use that as well

 

[Liveonce]

ppu .22hornet brass makes excellent .17hornet brass and is competitively priced.

 

[Rutland lad]

I shoot three calibres and was determined to use LAPUA for all - but then I got given about 300 once fired SAKO cases for my .308
That changed the plan.

 

[Miki]

A thought occured to recently (sometimes that happens) around the accuracy of a homeload depending on the make of brass.
I recently tested a thoery around brands known for good brass (in this case sako) vs other brands. I loaded up different makes of brass, but with the same load data in .243. I noticed quite significant group sizes between each group.

The one make of brass that i noticed was not as good groups was hornady. All brass was twice fired. Not annealed and fl sized and trimmes to the same length.

What have your experences been?

Annealing must make a difference, the aim beeing to get a consistent neck tension so that the bullet requires a similar 'push' to get it moving but the greatest effect will be (as @Outback said) the case capacity.
A larger volume will create less pressure behind the bullet whereas a smaller case capacity (with the same powder charge) will create higher pressure because the gases have less room to expand.
The timing of the pressure spike is also effected.
If the neck is looser than another then the bullet will move with less pressure behind it and the gas will expand into the chamber losing a smidge of pressure.
The above scenario will effect the MV and the group size will (as you say) expand, mainly due to the differing velocity.

Even measuring the case capacity of a single manufacturer will give some differences, across three different makers it can be quite significant and I think this will have a greater effect than annealing/neck pressure but every little thing makes a difference.
How much a difference it makes is difficult to define, and is that difference going to be detrimental to shot placement/accuracy in a hunting environment ....

What difference did you see in group sizes between the brands and at what distance ?

 

[Demetrius]

A successful competitive target shooter once told me that consistent neck tension trumps the other variables when reloading.
I've found that regular annealing is an important factor where accuracy is concerned, in my case for target shooting.

D.

 

[old 30-06]

Whatever I can get hold of. It all goes bang.

 

[Demetrius]

If you're looking for consistent sub 0.5 MOA groups at 300yds plus, then there's bang, and "bang".....

D.

 

[Stalker-of-the-deer]

Ive gone to just using norma or lapua as its consistent, hard-wearing and avalible

Hornady is to soft and the primer pockets loosen after a few firing

Federal is alright

Sako- had a bad batch where everyone failed to extract. Turns out the rim was too shallow and the extractor just rode over it

 

[Heym SR20]

Different brands of brass use different thickness of material which has an effect on internal volume. This will in turn affect the powder burn - a smaller volume will increase pressures and thus velocities and barrel vibrations.

As with anything in reloading, change one component and you need to rework the load. If you change the brand of brass, then it’s highly likely that your favourite load will not work. Chances are a little more or a little less will help.

As a material, brass is am alloy of copper and zinc, and there will be variations on the material used by different manufacturers. Any of the copper based alloys work harden with use. Every time you flex the material it will get harder and tougher. Heating it to just cherry red and letting it cool softens it again.

Such hardening has a big affect on how tight it grips the bullet. This again affects the pressure to which to the powder burns before the bullet starts moving. One of the reasons most factory ammo is firmly crimped is to give real consistency in tension. Worse is a cartridge with little tension with next having a bit of tension. You get better accuracy with good crimp and next one be a slightly firmer crimp.

PPU brass is bloody good. But if you want utmost consistency you will need to spend time weighing and measuring each piece and sorting it. There will be quite a bit of variation.

Lapua brass, by contrast is much more expensive as its much more consistent and you are paying for all the discards.

Does this matter for hunting ammo - probably not. For competition shooting - almost certainly

 

[Neddle]

Always found hornady to be lacking,Remington, Federal and S&B work fine but need alot of tlc when it comes to initial preparation, I prefer Norma over lapua too