Why is Hornady load data conservative?

[new308handloader]

On my way to getting all my reloading supplies and equipment. This morning I drove up to the Gun Show in Dalton, GA and picked up 8 lbs. of Hodgdon Varget and the 7th edition Hornady reloading manual. I really like the Horandy manual with all the "how to" stuff and all in color. However, I was comparing the load data (for the .308 Win 168 gr. with Varget) between the Hornady manual, the Speer manual, and Hodgdon (on-line) and the Hornady manual seems to to be conservative. The test data between all three were all using different brass and primers........but all were 168 gr., Varget powder, and 2.800" OAL. Speer and Varget data seemed to be very similar but the Hornady stopped at 42.7gr @ 2600 fps. What gives?

Speer (168gr. Match BTHP, 22" barrel, IMI Commercial brass, CCI 200 primer)
Varget start 42.0gr @ 2539 fps - Max 46.0 @ 2746 fps

Hodgdon (168gr. Sierra HPBT, 24" barrel, Winchester brass, Fed 210 primer)
Varget 46.0gr @ 2731 fps

Hornady (168gr A-MAX, 22" barrel, Hornady/Frontier brass, Fed 210 primer)
Varget start 35.5gr. @ 2100 fps - Max 42.7gr. @ 2600 fps

I will be reloading Hornady brass from TAP FPD fired in my rifle (cases are black & neck sized only), 168gr. A-MAX, CCI benchrest primers, and Varget....not sure where to start...can't find a "recipe" using thos components.

[muddober]

In a word "lawyers". If you were to get your hands on a 40 year old Speer Manual you would be amazed at really how conservative most all new manuals are.

[Bruce FLinch]

Originally Posted by muddober

In a word "lawyers". If you were to get your hands on a 40 year old Speer Manual you would be amazed at really how conservative most all new manuals are.

'nuf said'

[JLA]

Im right there with you 308. I use the hornady manual for my .223 RX10X loads for my AR and at max charge they wont lock the bolt open with the last shot. But very accurate though...

[new308handloader]

Originally Posted by muddober

In a word "lawyers". If you were to get your hands on a 40 year old Speer Manual you would be amazed at really how conservative most all new manuals are.

I get it....tells me what I needed to know (i think)....so I'm assuming that if the pressure was listed for that Max Hornady load if would be less than the max pressure limit of 52,000?

[muddober]

I don't know what the magic max pressure really is because I believe it varies from cartridge to cartridge. Mild steel will start to flow at about 60,000 psi yet there are loads out there that will reach those pressures with no harm being done to the gun or cases because of caliber and the very short period of time everything is subjected too. This can be better understood when one thinks of recoil. When firing any rifle one is subjected to recoil for only a millisecond or two, double or triple that time and you would be picking yourself up off the ground with possible injuries from the recoil. Same thing applies to pressure, meaning doubling the time the gun is subjected to pressures could cause to have a lot jagged parts flying about. I am not suggesting that one can load anything he wants to 60,000 psi but rather those high pressures can be seen in some rifle loads without harm to anything. AS an example loads in a shotgun should be kept to less than about 14,000 psi. Because the thin large diameter long shotgun barrel and slow moving projectile = increase in time = flying parts. There is far more stress put on a large bore barrel than a small bore barrel of equal pressure because the larger barrel has more square inches inside of it than the smaller barrel. Remember "psi" is "pounds per square inch". All meaning while you might load your 220 swift in the 60,000 psi range with no problems, you may not get away with those same pressuers in a 338 Win mag.

[buck460XVR]

I have found load recipes from bullet manufacturers to be more accuracy orientated and those recipes from powder manufacturers tend to lend themselves more for highest velocity. Thus bullet manufacturers recipes tend to be more conservative than powder companies. There are many starting loads from Hodgdon that are way above the levels that I will shoot outta my handguns. One reason I reference at least three different sources for starting loads and then start from a median point of all three. One deviation from this may be with powders like H110/W296 that do not download well.

[Marlin]

Originally Posted by muddober

In a word "lawyers". If you were to get your hands on a 40 year old Speer Manual you would be amazed at really how conservative most all new manuals are.

To clarify further, the key is - - -

the AMERICAN TRIAL LAWYERS ASSOCIATION or whatever it is now called since they changed the name to try to disguise their real activities from the name.....

[LDBennett]

No matter what the listed MAX is in the manuals, ALWAYS start at the starting load level first. Increase your load level in steps, watching for the sweet spot in accuracy and for signs of excessive pressures (see manuals for details) but never exceed the MAX load levels listed in any manual. I rarely if ever end up at the maximum load levels because the sweet spot for accuracy is reached first. But every gun is different.

At one point I had both a Browning A-Bolt and a Browning 1885 Single Shot, both in 223. Loads developed in the A-bolt were WAY too hot for use in the Single Shot by quite a bit (almost 2 grains!). Now this is from the same manufacture, Browning! I would mention that the hot A-Bolt loads did not exceed the loading manuals MAX.

On comparison to older manuals, I would caution against using such older data. Most of it was developed with inferior pressure data or none at all. Today's data is highly tested with improved equipment for pressure measurements and is safe. Yesterday's data might have been tested using pressure signs which can be an inaccurate measure of the real pressures. Today we have electronic pressure transducers and yesterday all they had were copper pellets that they crushed to get copper units of pressure (actual PSI vs. CUPS). While it is fun to blame the lawyers, common sense says to use the latest data for safety's sake or you may be paying with a hospital visit or a lawsuit from an adjacent shooter at the range hurt by your bad judgement.

Getting the last 100 feet per second velocity out of a cartridge is good for bragging rights but does little to assure good target scores. Most game animals don't know the difference between the accuracy loads and the hot load. Hit them in the right place and they go down just as hard with either load. Follow the manuals and be safe!

LDBennett

[JLA]

+1 LD.

[new308handloader]

Originally Posted by LDBennett

No matter what the listed MAX is in the manuals, ALWAYS start at the starting load level first.

LDBennett

Thanks LD....still brand new and haven't reloaded my 1st one yet...I think I would be best served to be safe as I get started.....then increase until I see presure signs and/or find the sweet spot.

[JLA]

in my experiences with medium capacity rifle cartridges you will generally find the 'sweet spot' somewhere around 90% capacity. But like LD said, EVERY rifle is indeed different.

[Halwg]

When you go to fire those first reloads, you'll be nervous as all get out. Once you put a few through the gun, and work on getting a good shooting load, you'll really enjoy it. I go for accuracy over velocity every time. Most of my hunting loads are not loaded to what the manuals list as max. I do, however, have one 30-06 load and one 35 Remington load that are above max, but they are the most accurate loads in those particular rifles and show no pressure signs.

[muddober]

Originally Posted by LDBennett

No matter what the listed MAX is in the manuals, ALWAYS start at the starting load level first. Increase your load level in steps, watching for the sweet spot in accuracy and for signs of excessive pressures (see manuals for details) but never exceed the MAX load levels listed in any manual. I rarely if ever end up at the maximum load levels because the sweet spot for accuracy is reached first. But every gun is different.

At one point I had both a Browning A-Bolt and a Browning 1885 Single Shot, both in 223. Loads developed in the A-bolt were WAY too hot for use in the Single Shot by quite a bit (almost 2 grains!). Now this is from the same manufacture, Browning! I would mention that the hot A-Bolt loads did not exceed the loading manuals MAX.

On comparison to older manuals, I would caution against using such older data. Most of it was developed with inferior pressure data or none at all. Today's data is highly tested with improved equipment for pressure measurements and is safe. Yesterday's data might have been tested using pressure signs which can be an inaccurate measure of the real pressures. Today we have electronic pressure transducers and yesterday all they had were copper pellets that they crushed to get copper units of pressure (actual PSI vs. CUPS). While it is fun to blame the lawyers, common sense says to use the latest data for safety's sake or you may be paying with a hospital visit or a lawsuit from an adjacent shooter at the range hurt by your bad judgement.

Getting the last 100 feet per second velocity out of a cartridge is good for bragging rights but does little to assure good target scores. Most game animals don't know the difference between the accuracy loads and the hot load. Hit them in the right place and they go down just as hard with either load. Follow the manuals and be safe!

LDBennett

While I agree in part I also disagree in part. I was not suggesting to use only old reloading manuals but rather trying to answer the threshold question: "Why is Hornady load data conservative" I stand by my assessment and statement that "lawyers" by implying that the threat of lawsuits has had an impact toward creating conservative loading data. I disagree that the old cooper crush method was unreliable as it was very reliable with the test barrel it was shot. Meaning the pressure test barrel whether done with the copper crush method or electronically, was the test barrel and in your gun could show different than the test barrel. I have been reloading for 50 years and I have done the hotrod thing which I must admit probably not the most prudent thing to do but I have never shot any of my loads that sent me to the hospital. I load for about 40 different cartridges from 25 auto to 50 BMG. The other reason in my view for the newer manuals being more conservative than older ones which I did not mention, though still tied to lawyers, is the fact of some of the guns that are now being built were never intended to see pressures of the modern bolt action rifle. The Browning single shot and A bolt LD provided was a great example. A Winchester Model 92 was never intended to see the 50,000 psi of 454 Casull nor the Model 95 Winchester to see pressures produced by a stiff 270 Win load (I know it was originally offered in 30-06), both examples of which are being offered today. I can't imagine shooting 23 grians of 2400 behind a 240 grain cast bullet in one of those super light weight 44 magnum guns that some manufacturers are making these days. Better yet just imagine writing a loading manual to safely reload a load for such a gun that won't break your wrist or stick the front sight in the shooters head with no flying parts, yet it would still bring out the "lawyers". I did not mention "lawyers" to be funny, I am as serious as cancer. There was nothing funny about Cessna Aircraft Company to cease and desist from manufacturing any series 100 or 200 airplanes for almost 20 years because they got tired of being sued. One such suit that put Cessna over the edge was the family of the deceased that successfully sued Cessna over a fuel cap design of an airplane built in 1948 that crashed in circa 1982.