MIXED HEADSTAMP RIFLE CARTRIDGE HANDLOADING?

[Vettepilot555]

I'm guessing this might have been covered in the past, but I couldn't find an answer to my exact question, so here goes... apologies if it's a stupid question and/or has been thoroughly covered before.

So I just bought a batch of 308 range brass, and have sorted it by headstamp. I ended up with some Federal, PPU, Lake City, etc., in batches of 40 to 80 or more. No problem there; just work up a load for each headstamp.

But I also ended up with around 200 or so in assorted headstamps. Some I have 3 of, some 8, some 5, etc., etc. What is the best way to deal with those??

Hypothetical case:

Let's say you have Federal brass, and it averages (xx) internal water volume, and you work up a safe, yet fast load for it. Could you then safely take a brand "X" headstamped case, that measures the SAME internal volume, and load it the same as the Federal??

What are acceptable safe internal volume tolerances in 30 cal brass?

Thanks for any and all insights,
Vettepilot

 

[Blue68f100]

Yes water volume is the best way to compare brass.That what I do with some years of LC. If you get an avg volume a lot of times you can mix lots. As far as what is acceptable depends on what your goals are. 1000 yrds I would want them as close as possible.

 

[Charlie98]

First things first... internal case volume will differ greatly between commercial and military 7.62mm brass. Were I you, I would segregate the military brass (LC) from the commercial stuff. I actually treat my PPU brass like LC, but I know it came from their 'white box' ammo, which is very close to LC... not their 'blue box' commercial ammo, which is different... or can be.

As far as your 200 'odd man out' mixed cases... if you develop a generic mid-range blasting load, you can use them there, but if you are actually loading for accuracy... I'd just set them aside or scrap them. There are too many variances in commercial mixed brass if you are trying to load them with any expectation of consistency. The smallest lot of brass I work with is 100 cases... I don't fool with 6 of these, 9 of those... they just go in the scrap bucket.

Let's say you have Federal brass, and it averages (xx) internal water volume, and you work up a safe, yet fast load for it. Could you then safely take a brand "X" headstamped case, that measures the SAME internal volume, and load it the same as the Federal??

Yes, you can do that and be reasonably safe in doing so. Again, I would not do it with 1) handloads designed for accuracy work, or 2) loads near or at maximum book.

Also, you will have to swage or cut out the primer pocket crimps on the military brass before you can prime them, unless that has already been done for you.

 

[IALoder]

First things first... internal case volume will differ greatly between commercial and military 7.62mm brass. Were I you, I would segregate the military brass (LC) from the commercial stuff. I actually treat my PPU brass like LC, but I know it came from their 'white box' ammo, which is very close to LC... not their 'blue box' commercial ammo, which is different... or can be.

As far as your 200 'odd man out' mixed cases... if you develop a generic mid-range blasting load, you can use them there, but if you are actually loading for accuracy... I'd just set them aside or scrap them. There are too many variances in commercial mixed brass if you are trying to load them with any expectation of consistency. The smallest lot of brass I work with is 100 cases... I don't fool with 6 of these, 9 of those... they just go in the scrap bucket.

This is exactly how I deal with them as well. As long as the "blasting load" with the oddball brass consistently cycles the gun, I'm not super worried about accuracy.

 

[AK Hunter]

My sorted head stamps I use for accuracy loads, the mixed head stamps I use for my plinking rounds where true accuracy is not a real problem.

 

[FROGO207]

Before you do any case prep you could weigh them first and sort by that if you don't want to go by water weight. Then always keep them with same group after processing. Think external dimentions are same so internal same on same weight. Or make them into blasting ammo as above. Also could sell as a lot or trade for a specific headstamp.

 

[Vettepilot555]

Ok. Great responses guys, and thanks. Regarding weight versus volume, I have seen where weight varies but volume is the same, and vice versa, where weights are close, but volume is different. It's a pain measuring volume, but I think it's the only way to really know...

It helps if you think of handloading as a hobby in and of itself, then the work isn't really "work" per se. A lot of brass prep, volume sorting, etc., is a one time deal, and if doing it saves brass and money, so much the better!

Vettepilot

 

[Vettepilot555]

Are there any "rules of thumb" whereby you reduce a powder charge "x" amount due to an "x" smaller case water volume??

Thanks!
Vettepilot

 

[Charlie98]

Are there any "rules of thumb" whereby you reduce a powder charge "x" amount due to an "x" smaller case water volume??

Thanks!
Vettepilot

Nothing that would produce quantitative results. Rule of thumb, in .308/7.62mm, is... when going from commercial to military brass is to reduce 1grn and work up. For example, if you are loading 44grn IMR4895 under a 150grn bullet in Federal cases, you would reduce to 43grn IMR4895 if you switched to LC brass, etc. This is a generalization, of course... and I wouldn't recommend you do the reverse, meaning I would not arbitrarily bump UP 1grn if I was going from LC to Federal, if you see what I mean.

Water volume is, really, the only way to measure case volume in a consistent manner. I don't reload to that level... yet. If I were to do that, I would... as I suggested... just start with something like Lapua brass and roll with it. My reloading process is proper, and to some extent meticulous, but I'm real enough with myself that I know I can't shoot the difference between minor differences in case volume across a single headstamp.

 

[Jim Watson]

The old old NRA formula, back when we shot .30-06s, was to reduce powder charge by one grain for every 11 grains greater case weight. This was NOT a license to increase loads just because some brass weighed less and was presumably larger volume.

 

[FROGO207]

Ok. Great responses guys, and thanks. Regarding weight versus volume, I have seen where weight varies but volume is the same, and vice versa, where weights are close, but volume is different. It's a pain measuring volume, but I think it's the only way to really know...

It helps if you think of handloading as a hobby in and of itself, then the work isn't really "work" per se. A lot of brass prep, volume sorting, etc., is a one time deal, and if doing it saves brass and money, so much the better!

Vettepilot

"Save money" ha ha ah yeah rite!
That has NEVER happened in 30+ years reloading.

 

[Vettepilot555]

Well, that's true. Now that I handload, I actually spend about 10 times as much. But I am having fun!

Vettepilot

 

[jmorris]

So I just bought a batch of 308 range brass,…

But I also ended up with around 200 or so in assorted headstamps. Some I have 3 of, some 8, some 5, etc., etc. What is the best way to deal with those??

Sell them as a batch and let the next guy deal with them.? If you need 200 more, buy another batch and grab the federal, PPU, LC, (stuff you want) out of that batch sell the small quantity mix from that batch as well.

 

[Ranger99]

Sell them as a batch and let the next guy deal with them.? If you need 200 more, buy another batch and grab the federal, PPU, LC, (stuff you want) out of that batch sell the small quantity mix from that batch as well.

^ ^ ^ ^ THIS ^ ^ ^ ^

JMHO- life is way too short to spend so
much time dilly dallying with questionable
brass. If they're not obviously in the
best of condition or if there's the least bit
of doubt, send them down the road and
find some you can absolutely trust.
Another opinion- i have more trust in data
from manuals that the different manufacturers have spent many dollars to
compile, more so than some of the experts
that have multiple over pressure related
failures. I always work up from the suggested starting loads and don't skip up
to max and back down like so many seem
to want to do these days. It may be an
old fashioned attitude, but I still have my
eyes and body parts and haven't damaged
any firearms

 

[horsey300]

Are there any "rules of thumb" whereby you reduce a powder charge "x" amount due to an "x" smaller case water volume??

Thanks!
Vettepilot

I have to ask, how much accuracy at how many yards do we wish to obtain and (no offense) are you and your rifle capable of telling the difference?

 

[bluejay75]

Best reserved for cast bullet loads or reduced loads. The typical powder you would use for these will be completely burned before the bullet is down the barrel a few inches and they are usually not position sensitive. Unique, 2400, Red Dot, 3031 or 4198 works well in mixed brass.

I have near a gallon sized bag for this exact reason. Norma, Winchester, PPU and most other HSs I don’t use end up in this pile. I can get 1.5 MOA out of my “Armageddon” 18.5 AA9 and 180 grain 308 load using a PB Ranchdog 310 sized powder coated clear bullet. Also works great with 24.5 grains of 2400 and a 150 RN Nosler Etip (30-30 bullet)

 

[Vettepilot555]

Not doing long range with 308 at this time, to answer the application questions, and when I'm shooting groups, it's same headstamp and all the usual prep. (Probably more case prep than most 'cause that's just me, (anal).

These mixed HS would be for hopefully 2 moa or less plinking ammo out of a nice AR10.

Not a bad idea just to use them for cast bullet use though...

Thanks,
Vettepilot

 

[horsey300]

Not doing long range with 308 at this time, to answer the application questions, and when I'm shooting groups, it's same headstamp and all the usual prep. (Probably more case prep than most 'cause that's just me, (anal).

These mixed HS would be for hopefully 2 moa or less plinking ammo out of a nice AR10.

Not a bad idea just to use them for cast bullet use though...

Thanks,
Vettepilot

"2 moa or less" you're overthinking this by a long shot. Grab a decent, fairly slow powder, like I4350 or I4451, find the most accurate load (probably close to starting load for 165s), and load all 200 cases, go to the range and have fun practicing, once you see THOSE groups start shrinking with no change to load, see how much you can get them to shrink playing with seating depth and shooting technique, THEN worry about sorting headstamps etc etc! I have a TON of mixed brass and I can keep the groups sub moa, harder to keep them sub .5 though, using those same loads in the same brass, my kids can print .75-1.5 moa loads, then 2 or 3 weeks later they're less focused and print a 3 moa group with the same loads. Now if we were ALWAYS chasing <.5 then we'd be putting more work into the load process but really we're just enjoying shooting, outdoors, bonding, etc and towards end of summer we practice weekly to be ready for game and yotes and they get back to consistency and we've changed nothing about the mixed brass, charge, bullets, or seating depth. With something like a starting load of imr4451 or ramshot big game or h4895, (IF your rifle likes it) with a 165, you'll need more than 4 gr capacity difference to really get you to notice that 3 Winchester stamped rounds print off of the 5 federal stamped rounds when the goal is just to be 2 moa.

 

[twarr1]

I load my odd lots with a mild load and cheap FMJ bullets. I’m also quick to take the ball peen to questionable brass.

 

[Howa 9700]

For all practical purposes, I'm a newb at loading for metalica, so consider the source. But as I am coming to understand things, assuming all else being equal, it seems the only thing that happens when you change cases....assuming slight differences in internal volume, is the pressure inside the case increases at a different rate and different amount. Smaller volume suggests pressure will spike sooner and maybe more, plus you may get a different burn pattern. That is going to manifest itself by pushing bullet down the tube at a different speed or rate.....and affects the timing of it. In short, velocity changes and when that happens, the bullets start to spread high and low at distance.

Now comes the next question......don't you do the same thing when you change bullet seating depth?

Are the nodes observed by changing seating depth really nothing more than fine tuning the pressure spike? Not a jump to the lands?

 

[Dale Alan]

Are the nodes observed by changing seating depth really nothing more than fine tuning the pressure spike? Not a jump to the lands?

The jump/jam plays into the variables...how much pressure/gas gets ahead of the bullet at different jumps, or none at jam . Related to pressure of course , but you have many variables . Powder charge and seating depth both need tweaking to get the utmost accuracy .
Also jump/jam can be bullet specific , some do much better either jumped or jammed..barrel/rifle come into play also .

 

[Reloadron]

The below spread sheet was worked up using Remington Peters, Winchester, WCC 10, LC 13 and Federal brass in 308 Winchester cartridges. All cartridges were sized and trimmed to 2.005" and their external dimensions as close as I can get them. During sizing the primer pockets were filled with 1.8 grains of modeling clay. This is reflected in the filled weight as a tare. The cases were just selected at random from larger lots of once fired brass, ten cases of each totaling 50 cases. I used distilled water but doubt it matters.



The case volumes are expressed in cubic centimeters. The average volume, standard deviation volume, MAX volume and MIN volume are listed. Unfortunately I have yet to load and fire these cases over my chronograph but looking at the case volume across the board and with a focus on Standard Deviation (lower the better) I doubt for the listed cartridges it will matter much. The WCC and LC brass are GI brass and the WCC 10 brass has worked out very well for me. It has also been my experience that GI brass is not always heavier nor does it yield lower case volume. Everything be it commercial or GI will vary lot to lot at manufacture.

I would just load using credible load data from the manufacturer and not overly worry about head stamps unless as mentioned you are wanting to build match ammunition.

Ron

 

[Charlie98]

Best reserved for cast bullet loads or reduced loads. The typical powder you would use for these will be completely burned before the bullet is down the barrel a few inches and they are usually not position sensitive. Unique, 2400, Red Dot, 3031 or 4198 works well in mixed brass.

Now that I'm thinking about my brass stash upstairs... you are right. I save my FC and Hornady brass for my Savage 99 that only gets IMR4198 and cast bullets. It allowed me to switch some of my Prvi brass back to the M1a pile.

 

[bluejay75]

Talk about mixed! I had forgot that I use necked up 243 and 7mm-08 in that pile as well. Just grabbed a handful to check. This is a 1.5 moa load.

 

[Blue68f100]

The below spread sheet was worked up using Remington Peters, Winchester, WCC 10, LC 13 and Federal brass in 308 Winchester cartridges. All cartridges were sized and trimmed to 2.005" and their external dimensions as close as I can get them. During sizing the primer pockets were filled with 1.8 grains of modeling clay. This is reflected in the filled weight as a tare. The cases were just selected at random from larger lots of once fired brass, ten cases of each totaling 50 cases. I used distilled water but doubt it matters.

View attachment 1007914

The case volumes are expressed in cubic centimeters. The average volume, standard deviation volume, MAX volume and MIN volume are listed. Unfortunately I have yet to load and fire these cases over my chronograph but looking at the case volume across the board and with a focus on Standard Deviation (lower the better) I doubt for the listed cartridges it will matter much. The WCC and LC brass are GI brass and the WCC 10 brass has worked out very well for me. It has also been my experience that GI brass is not always heavier nor does it yield lower case volume. Everything be it commercial or GI will vary lot to lot at manufacture.

I would just load using credible load data from the manufacturer and not overly worry about head stamps unless as mentioned you are wanting to build match ammunition.

Ron

Ron what was the condition of the cases? Did they have powder residue, or sparkling clean with SS pins?

I have found in my testing that you need to add a drop of soap to 8 oz of water to break the surface tension. Does not take much but it prevents bubbles from being trapped.