How do the factories load "universal" high performance cartridges??

[rbTanzan]

So we've all seen it advised a bazillion times; "....work up a load slowly in your gun, watching for pressure signs". And, "If you change any component, start over on load workup with a reduced charge".

Now sometimes it is difficult when reloading to match the performance, at least in terms of velocity, of factory loaded ammo. To be competitive, and keep the buying public happy, (and brand loyal), factory ammo has to have relatively high velocity performance for each given cartridge.

So how do they do it? How do they make rounds with respectable velocity, that are safe in "any gun of modern manufacture in good condition"??

I realize they use powders that we don't have access to, but where's the "magic"? High performance loads, that work in ANY gun, (and are safe) ,with no gun specific load workup.

What am I missing here??

Vettepilot

The reason for the handloader to exercise caution is that different powder lots may burn at different rates, different cases may have different volumes up to, e.g, 3 grains, different brisance in primers, different diameter in bullets, different friction coefficients, malleability, etc. So the handloader must verify safety when any changes are made, including seating depth.

The factories, of course, have already verified the safety of the particular combination before massive production. Once the whole combination has been determined to be safe and within SAAMI spec, then they can mass produce safely, as long as they don't change anything. They know that some batch of new powder is not going to suddenly 'blow a primer' because they won't add such a powder without testing and "working up," like we do.

PS: I remember blowing a couple of primers with factory 'Czech' ammo in Africa in the 80's. The bullets had a lot of slop inside when shaken, so I suspect that they used a too fast powder to save costs and meet production goals.

 

[Mike Matteson]

The only time I use factory Ammo is rim fire, 5.56 and pistol, if it's a good deal. Otherwise I hand load everything except for shot-shell with steel shot. If I see a real good deal on shot shells for traps, skeet shooting, and the case is what I want to reload with. I will buy factory loads. I save the cases no matter which gauge, when out in the field. Presently setting up to have a 6mm built. Just haven't set on a case configuration just yet. I am buying reloading items presently as item come up on sale. I am not going to shot at matches either, just setting up for longer ranges out to 700yds or so. I love the work up of a round for a rifle. That way I get what I think I want. Once I settled on a bullet weight, and get the performance out of the rifle that all I shot from that rifle from then on.

 

[cynicrit]

I suspect that anytime a reloading formula is published, there is someone involved who understands tort law. This is addressed by going to the lowest common denominator i.e. the most reckless, careless, or just plain human person who might be using that load. Now there's a can of worms.
Most factories load using virgin brass, with propellants whose characteristics they specified, with bullets they either manufacture or set specs for, on machines that they maintain and control. Most of all, this is done by people who have a very deep interest in not screwing up, overseen by people who are even more interested in not screwing up. There's something to be said for pride and professionalism. Not throwing shade at anyone, most reloaders are super conscientious and take great pains to get it right. Some are the shooting culture's equivalent of rocket scientists. And reloaders who don't measure up either give up reloading (because their ammo sucks or they can't afford to keep repairing guns) or end up in the ER, or end up in the Darwin Awards. It's just that a factory has a higher degree of control over every aspect of production. And they test,test,test. So, if they occasionally push the envelope, they can do so with confidence, knowing that they have taken great pains to cover their backside.
That's just my worm's eye view.

 

[greatwhitehntr]

It is all about PSI. I got a 1000 once fired cases and 500 decommissioned military cases in 300 win mag, in the 500 was 2 loaded rounds and I wish I would have went in reverse order (hind sight) I ran out with the labradar to see how fast they were going with the 220mk in them and locked my gun up solid had to take the barrel off and beat the case out. Went home and checked the once fired cases and the were huge. I could not size half of them. My 26" barreled 300 wm had that 220MK come out at 3015fps that is humming. Obviously the military has a different reamer spec and they don't give a crap about the case one and done.

 

[Lee Goodwin]

Nosler data is cool in that it shows you several powders they used and their most accurate load...for that cartridge and bullet weight. I believe the barrel length is there too. So for retail ammo loaders they gotta be using a set up that mimics the rifle that the customer has in his hand. Then there is hunt loads and target loads. And, probably a bunch more. And I bet their recipe changes with the times. I bet they experiment with duplex loads. There's a bunch of different ways to bake that bread.

 

[supersubes]

It is all about PSI. I got a 1000 once fired cases and 500 decommissioned military cases in 300 win mag, in the 500 was 2 loaded rounds and I wish I would have went in reverse order (hind sight) I ran out with the labradar to see how fast they were going with the 220mk in them and locked my gun up solid had to take the barrel off and beat the case out. Went home and checked the once fired cases and the were huge. I could not size half of them. My 26" barreled 300 wm had that 220MK come out at 3015fps that is humming. Obviously the military has a different reamer spec and they don't give a crap about the case one and done.

Not wise to shoot MK248 mod 1 ammo in guns not chambered for it. Its loaded for 68k psi in their chamber. You probably hit 75-80k.

 

[AaronSkipDavidson]

This is that hardest to achieve product feature we offer.

 

[Bob2650]

The key to making ammo that performs well in many different rifles is the Tangent Ogive.
VLD and secant ogives can have a better ballistic coefficient but they are picky about bullet jump. The tangent ogive is usually very forgiving about differences in bullet jump. The Sierra Match King bullet is one of the biggest factors in the sucess of Federal Gold Medal Match ammo. A VLD would fly better but the tangent launches more accurately from a wider range of chambers.

 

[BrentM]

Duplexing/compounding powder. Proprietary blends.
Virgin Brass.

There is no real magic to it other than controlling the feed of the powder charge into the brass.

Often factory ammo works in a wide range of rifles if the chamber is saami spec and the fps is quite close to the box data if the barrel is within reasonable spec of the test barrel.

It is very common to see virgin brass handle significantly more charge due to the undersized nature of the brass. Once the brass if 1x fired the brass will expand and even after resizing likely not match virgin level. After several firings it will be a fair bit larger in the web and a virgin brass hot load will be dangerous in multiple fired and sized brass. Work hardening etc has a lot do with case body expansion charateristics.

 

[antelopedundee]

One reason Hornady Match shoots so well in their cartridges is because they took the time to test the bullets they load to see what bullet jump they preferred, then loaded their ammo with their bullets at those specs for rifles chambered in their cartridges.

When they run bullets they test fire them every so often so they probably know what conditions give the best test results and use those to load their ammo as long as it fits into a magazine. The used to load their cutom ammo on Pro-Jector presses. The gunsmith who has smithed all of my rifles used to fit and chamber all of their test barrels.

 

[FlyGuy11]

In my 28 Nosler with Nosler 175gr. Factory ammo I have seen ejector marks. I didn't know if that was normal for such a big cartridge or not. 1st factor ammo I have shot in years because I had a hunt with no time for load development. I would like a manufacturer's input but due to liability these days I feel we would get the "we load within SAAMI specifications " line. I believe Nosler, Sierra, and Berger have some of the best data.

 

[Velvet]

I think they use some kind of OCW method.

 

[FlyGuy11]

I think they use some kind of OCW method.

OCW?

 

[Kay0404]

I get ejector marks on my NV 6.5Grendal AR-15 with Hornady ammo.. Probably 3/5 cases. Not bad, just a little dimple, but compared to other factory ammo, I can't tell that it is hot, maybe just the Hornady softer brass.