Mixing cases

[Oldbloke]

A question for the more experienced re-loaders here. Rather than just googling it.
I have 1000 55gr Super Roos I'm about to start using in my 223. So this will be a change of bullet. Currently getting about 0.7moa with the old 55gr soft points I'm using. (very mild load) This is strictly for hunting usually pretty sensible distances, say out to 170 yards.

Long story short I have lost about 70-80 S&B cases I have used in the past and now have a mix of S&B, Winchester and ADI. All sorted into brands. About 60 S&B and about 40 of Win & ADI. I will be keeping them sorted.

Ill load a few test rounds tomorrow to find a decent load/group when I get a chance to test them.

I have no intention in chasing velocity. The first load I get shoots good groups will do me, so I expect lowish pressures. (S&B Cases)

Now the question. If I develop a load using one brand, with S&B cases is there likely to be a significant difference in accuracy if I use the same load in the others?
Please don't tell me to test all of them. Just wondering what peoples experience has been & what to expect.

[bladeracer]

It will depend on differences in case volume, flash hole diameter and neck tension I reckon. If there are significant differences in those then there could be significant differences at the target. If the differences are small there might be little measurable difference at relatively close ranges. As you are already aware, there is only one way you will know for sure, load ten rounds in each type and shoot two 5rd groups with each at 150m (or whatever maximum range you have in mind for them). Compare the group sizes and positions, and overlay all the groups over each other to see if the 30rd "group" size is significantly larger or significantly off your point of aim. With different brass it's less a matter of whether that brass groups as well as the other brass as much as whether it puts them to the same point of aim.

I keep a few hundred ADI pieces for my "good" ammo, and a few hundred (very) mixed brass for my reduced and plinking ammo, simply because this stuff is only for short ranges where the accuracy really doesn't much matter.

A question for the more experienced re-loaders here. Rather than just googling it.
I have 1000 55gr Super Roos I'm about to start using in my 223. So this will be a change of bullet. Currently getting about 0.7moa with the old 55gr soft points I'm using. (very mild load) This is strictly for hunting usually pretty sensible distances, say out to 170 yards.

Long story short I have lost about 70-80 S&B cases I have used in the past and now have a mix of S&B, Winchester and ADI. All sorted into brands. About 60 S&B and about 40 of Win & ADI. I will be keeping them sorted.

Ill load a few test rounds tomorrow to find a decent load/group when I get a chance to test them.

I have no intention in chasing velocity. The first load I get shoots good groups will do me, so I expect lowish pressures. (S&B Cases)

Now the question. If I develop a load using one brand, with S&B cases is there likely to be a significant difference in accuracy if I use the same load in the others?
Please don't tell me to test all of them. Just wondering what peoples experience has been & what to expect.

[SCJ429]

You are adding another variable to your loading. If you are happy with 0.7 of an inch but one MOA is unacceptable then mixed cases is not for you. If you are happy with three MOA groups, then mixed cases will be fine. If you tested 100 different brands of cases, you would probably fine 100 different case weight and internal capacity. If you happen to use the smallest and the biggest, then your groups are going to be woeful.

[Wyliecoyote]

I use S&B, Winchester and ADI cases in my 223s. The S&B weigh around 102.5 grains. The Win and ADI run from 92 to 94 grains. My load is 27 grains of 2208 and 55 Rooload in the Win and ADI cases. You cannot get 27 grains of 2208 into the S&B cases without seriously compressed loads. To match the velocity and accuracy the S&B cases are loaded one full grain less at 26.

[Oldbloke]

I use S&B, Winchester and ADI cases in my 223s. The S&B weigh around 102.5 grains. The Win and ADI run from 92 to 94 grains. My load is 27 grains of 2208 and 55 Rooload in the Win and ADI cases. You cannot get 27 grains of 2208 into the S&B cases without seriously compressed loads. To match the velocity and accuracy the S&B cases are loaded one full grain less at 26.

Thx wylie that's a good point. And good info. I'll weigh a few cases tomorrow.

[Lazarus]

I've only been reloading for a few years so I'm a babe in the woods, but I only use ADI brass, and second the sentiment about weighing cases.

The best load I've had was with Roo Max 55gn sn in 93.3gn cases, about 12mm at 250m, 18mm at 300 but by 400 it's over 90mm.
Trouble is I only have 15 cases the right weight so it's more just to see, rather than the average.

[animalpest]

I was recently load testing for my .223 and .243. With the .243 I had a flyer in the group, about 1.5 inches away. When I checked the case after firing, I noticed it was a different brand.

It did the same thing with the .223 when I mixed cases, although it was less (about 3/4 inch).

[Oldbloke]

Thks animalpest and lazarus. That's good info. Just what I was looking for.
Been loading for years. But always used one brand of brass. So,,, in the past always used S&B for the 223. Been no obvious issues. But lost about half the cases in a robbery recently. Hence the question.
I'm not trying to head shoot rabbits at 250 yards. Mostly chest shot foxes under 150 yards. (Whistling,)
But, it can definitely be a significant change of poi. Probably wouldn't matter for Sambar but target is a bit smaller in this case.

I'll weigh a small sample of each tomorrow. Report back.

[Billo]

most cartridges will have 2 accuracy nodes, load at the low 1 and I doubt you'll accuracy will be greatly affected.

I recently changed brass in my 357 from Fed to Geco and found it made bugger all difference as I chose the low node and which was 0.6gr lower from the high node. If your chasing out right speed and accuracy then thats a different story.

[animalpest]

most cartridges will have 2 accuracy nodes, load at the low 1 and I doubt you'll accuracy will be greatly affected.

I recently changed brass in my 357 from Fed to Geco and found it made bugger all difference as I chose the low node and which was 0.6gr lower from the high node. If your chasing out right speed and accuracy then thats a different story.

What I also found was that velocity decreased by about 100-150 fps when I changed cases. Same happened with my 25/06. Group sizes went from 0.5 - 0.75 right out to 1.5 - 2.0 inches until I upped the powder charge.

So your node may not be there when using different brass.

[Billo]

I would agree with a large case like a 25-06 then its a diff story, the OP mentioned a 223 so completely different story.

Id be surprised if you found much more then 0.1 gr diff in case capacity with diff brand cases with the 223

[Oldbloke]

I would agree with a large case like a 25-06 then its a diff story, the OP mentioned a 223 so completely different story.

Id be surprised if you found much more then 0.1 gr diff in case capacity with diff brand cases with the 223

My guess is that it's all relative. Bigger cases = bigger variation. I'm not concerned with a 100fps change in speed. Just poi.

[Lazarus]

I would agree with a large case like a 25-06 then its a diff story, the OP mentioned a 223 so completely different story.

Id be surprised if you found much more then 0.1 gr diff in case capacity with diff brand cases with the 223

G'day Billo

As stated I only use ADI brass, I also only have 250 cases but there's nearly 5gn difference between the heaviest and the lightest of them.

The difference between different brands I wouldn't know.

[Oldbloke]

I would agree with a large case like a 25-06 then its a diff story, the OP mentioned a 223 so completely different story.

Id be surprised if you found much more then 0.1 gr diff in case capacity with diff brand cases with the 223

Bill is talking about case capacity. Lazarus is about case weight.

[Larry]

Before you sort by weight make sure you FLS and trim all the cases as a long neck will weigh more than a short trimmed one.

[Billo]

I would agree with a large case like a 25-06 then its a diff story, the OP mentioned a 223 so completely different story.

Id be surprised if you found much more then 0.1 gr diff in case capacity with diff brand cases with the 223

Bill is talking about case capacity. Lazarus is about case weight.

Correct Oldbloke

[Lazarus]

Isn't weight an indication of capacity?
Like I said I've only been loading for a few years so the things I don't know far outnumber those I do.
They can't be bigger in the outside dimensions or they wouldn't chamber so heavier cases should have slightly thicker walls and consequently a smaller internal capacity. Or am I missing something obvious, wouldn't be the first time.

Now that's just my theory, I know many things can be counter-intuitive

[on_one_wheel]

If I were to mix cases I'd be keeping them in unmixed batches, I wouldn't be able to help myself. I'd Probably even chronograph them just so I knew how they performed against my primary case brand.

Iv found enough case variation in my Winchester cases to warrant sorting into batches, once I did that my groups tightened up from around .5 to .3
At least that's what I've convinced myself

That stuff makes all the difference when your shooting offhand in gusty winds, peering through blurry eyes while gasping for breath with your heart pounding 200 bpm.

Sometimes I wonder why I even bother measuring my powder

[Oldbloke]

Isn't weight an indication of capacity?
Like I said I've only been loading for a few years so the things I don't know far outnumber those I do.
They can't be bigger in the outside dimensions or they wouldn't chamber so heavier cases should have slightly thicker walls and consequently a smaller internal capacity. Or am I missing something obvious, wouldn't be the first time.

Now that's just my theory, I know many things can be counter-intuitive

Thats right. I just thought you both might be confused.

[Oldbloke]

OK. I'm a realist and understand that I don't need 0.3 moa. Happy with MOA or a tad less if doable. I don't target shoot so strictly hunting and sensible ranges.

OK. I did a bit of a stock take on all of my 223 cases and was surprised, almost all of my S& B cases were stolen. (bugger my original cases) And a few Winchester cases gone too.

Here is the result of the stock take and weighing exercise. BTW all cases weighed had been cleaned/sized and trimmed.

Case weights.JPG (23.1 KiB) Viewed 2222 times

I normally have a few "squib" loads so it looks like they will be the S&Bs. (don't use them much)

Winchester and ADI are surprisingly close in weight so I think I will test/develop loads in the Winchester cases and treat the ADI as being the same. This will give me over 100 cases. Plenty for my needs.

What do you blokes think?

[Lazarus]

I'm surprised at the extra mass of the S&B.

It would be interesting to see how parallel loads performed, ie same powder weight and seating depth in the heavier S&B compared to Win or ADI.

[Oldbloke]

I'm surprised at the extra mass of the S&B.

It would be interesting to see how parallel loads performed, ie same powder weight and seating depth in the heavier S&B compared to Win or ADI.

That's why I've asked the question.
Everyone knows it matters, but by how much?
Could do that I guess but can't be bothered to be honest.

[Larry]

I think you are on the right track and getting rid of the remaining S&B cases might be the solution.

[Oldbloke]

I think you are on the right track and getting rid of the remaining S&B cases might be the solution.

The squib loads were developed back in 2015. Not long after I purchased the rifle. So pretty sure they were S&B cases.

viewtopic.php?f=3&t=4991

[animalpest]

Isn't weight an indication of capacity?
Like I said I've only been loading for a few years so the things I don't know far outnumber those I do.
They can't be bigger in the outside dimensions or they wouldn't chamber so heavier cases should have slightly thicker walls and consequently a smaller internal capacity. Or am I missing something obvious, wouldn't be the first time.
Now that's just my theory, I know many things can be counter-intuitive

It can be outside measurements are different but not once fired in the same chamber. The differences in weight can be wall thickness, the depth of the web and the size of the extractor Grove.

[Oldbloke]

Yes agree. It's just an indication, as he said.

[SCJ429]

Your results are pretty typical where different different brands of cases can vary by 10 grains. If you are using Remington or Winchester brass, they can vary from case to case from the same batch by 6 grains but the average for those two brands is about 93 grains. If you mixed them the variation from the factory is the biggest factory. If you did mix in a case that weighed 100 grains it would take up more room in your chamber making the combustion chamber smaller. A bit like seating a projectile much deeper into the case and taking up some of the space in the chamber.
At the end of the day you can get 223 cases very cheaply or for free, best to sort them for better results.