Different Listed Max Charges from Equally Reputable Sources?

[GeoDudeFlorida]

Based on lyno being basically gone, charts should be changed to Lyman #2. It's a much more reasonable standard based on current material availability.

I don’t have the 51st so I don’t know if they switched back or not. For me personally and my style of shooting the 44th and 45th are more useful. But as for the topic of the thread, it’s the how and what that sets data apart even when comparing “similar” components.

 

[DMW1116]

I checked the Lyman 50th edition. It doesn’t list a 147 grain JHP, but uses a 147 grain FMJ instead. However the max for that is a rather stout 5.8 grains of HS-6 at 30,000 psi. I’m not too worried about the increments of 5.1 grains and under. I’ll see how they do then decide on the 5.3 grain charge.

 

[Remington1911]

I am trying to think if I have ever loaded max....and yea I have on only one thing. A 38 shooting out of a 38/357 lever gun....my thought being if it can take 357 pressures max pressure on a 38 should be a cake walk. And really it did not shoot any better....worse.

Even when I hunted I never loaded to max, I started where I knew the bullet needed to perform, and moved up from there, and when I got to something the gun liked, usually somewhere between what I had loaded I stopped. I don't think I ever came across well .8 is better over .5, so the next step up 1 should be even better.....usually .5 is good, .8 a little worse, so I roll back to .5 and call it a day.

Now in just using guns as a hole punch I will load the same way, and when I see .5 being good I will start walking up in .1 steps....being just fun, this is part of the fun, but if .5 puts the bullet out of that gun with good stable numbers, and accurate enough for the off switch of what I am shooting at, good enough.

 

[Howa 9700]

Concern here seems to be with pistolas, but I have noticed the same thing with various rifle rounds. Max load in Lyman 50th or from Hornady a mild load as far as Hodgdon is concerned. Some as much as 3 grains or more in a 45 to 50 grain load. If memory serves, there was also a load I was working on with IMR4064, where I had a full case of powder and load data said I could go another 2 grains more. Got me thinking......does anyone actually check this stuff?

So in the load data sheet I worked up for each load, I now try to find and list 3 different load sources.........consider the source, consider the load's published velocity estimate and compare that to the velocity a factory load for that bullet. From all that, start at the bottom and work my way up checking velocity and looking for signs of pressure along the way.

As a consequence, I have found good results at the highest max loads..........and have run into signs of pressure way below max. Do that a couple times and you develop a profound respect for the process.

 

[DMW1116]

Loading 308 rifle rounds was where I first encountered such large differences. That’s also when I changed my policy to go with Hornady data for Hornady bullets. I had a rifle load give me problems just above the Hornady max but did fine pressure wise more than a grain higher with different bullet.

 

[buck460XVR]

Different data has been this way since the beginning of time, manuals and the internet.

It doesn't mean one or the other is wrong or bad. Just different tests by different people on different days. Both are within acceptable pressure standards even though Hornady doesn't list it exactly.

^^^This. One reason I generally always use at least three reputable sources when developing a new load. That way I can compare and take an "average" approach to where to start and where to stop on the ladder. No reputable source is going to publish a dangerous load recipe for use in a modern and well working firearm. It may be a "tad bit hotter" than others, but it will not blow up your gun. Sometimes, there comes a point where adding more powder does not add any more velocity, so sometimes, that's where the "max" is and not pressure.

 

[GeoDudeFlorida]

Concern here seems to be with pistolas,

Because this:

I am loading some 147 grain XTP bullets from Hornady for 9mm. I'm using HS-6 powder and CCI 500 primers

I have noticed the same thing with various rifle rounds. Max load in Lyman 50th or from Hornady a mild load as far as Hodgdon is concerned. Some as much as 3 grains or more in a 45 to 50 grain load. If memory serves, there was also a load I was working on with IMR4064, where I had a full case of powder and load data said I could go another 2 grains more. Got me thinking......does anyone actually check this stuff?

So in the load data sheet I worked up for each load, I now try to find and list 3 different load sources.........consider the source, consider the load's published velocity estimate and compare that to the velocity a factory load for that bullet. From all that, start at the bottom and work my way up checking velocity and looking for signs of pressure along the way.

As a consequence, I have found good results at the highest max loads..........and have run into signs of pressure way below max. Do that a couple times and you develop a profound respect for the process.

Check the testing fixtures and barrels used. I'm pretty sure Hornady, Hodgdon and Lyman use different testing apparatus and methods. That's why it's never an apples-to-apples comparison between books.

 

[crash813]

Just wait until you start loading things that have no numbers for the caliber, bullet type, and powder! Then you start searching for 'signs of overpressure' in threads and then everyone disagrees with that.

eg - coated lead .... somewhere between lead and plated? Does it depend on the coating? What if there's no plating, just fmj.... or worse, just xtp. What if there's just one bullet type??? There's monsters in these waters!!!

 

[GeoDudeFlorida]

There's monsters in these waters!!!

Ah, yes, the wily Kabooms! Closely related to the Jagular and Hephalump.

 

[AJC1]

Just wait until you start loading things that have no numbers for the caliber, bullet type, and powder! Then you start searching for 'signs of overpressure' in threads and then everyone disagrees with that.

eg - coated lead .... somewhere between lead and plated? Does it depend on the coating? What if there's no plating, just fmj.... or worse, just xtp. What if there's just one bullet type??? There's monsers in these waters!!!

In that situation I'd be trying the military red dot loads for plinking... no reason to go wild.

 

[jmorris]

I have seen conflicting data from manuals on the same page. Probably the equipment and environmental influence.

30 years ago they thought 5.1 was max.

 

[DMW1116]

I think I’ll just shoot them and see. Clarity is becoming less and less likely.