I would like the opinions of the group on this subject.
All the gun rags, all the bullet and powder companies, and all the barrel manufactures will tell you to start at reduced loads and work up. I recently purchased a 300 Weatherby Mag. Can someone tell me of a single factory loaded 300 Weatherby Mag. cartridge that is a reduced load?
That got me thinking, is all this reduced load stuff something the above groups say to cover their butts? Does anyone have a modern gun that cannot handle the max pressure load listed in any gun rag or reloading book?
I can see this approach with a wildcat cartridge that has no published data, but a standard cartridge?
I would appreciate your opinions on this.

Put simply...

How many people in this world load with exactly the same precision (or lack of) as you?

How many people are shooting your firearm?

How many are using the same brass, bullets, primers and powders as you?

How many live in the exact same environment as you?

You start low and work up because you do not have access to the same powders the factory does. Therefore, you do not know how your rifle will handle a given load with a given bullet. There are a myriad of variables in loading beside bullet and powder. There are case volume, primer, seating depth for example. All these effect pressure.

Because you don't know how all this is going to come together in your rifle, you can't start at the top and work down. (Well, you can if you are will in assume the risk you might end up wearing your rifle instead of carrying it!)

Classically, you start with a mid range powder, a mid weight bullet and a mid weight powder charge and run a test against given data in a good loading manual (or two or three manuals). It is comes out about where it ought to, then you can move up a little and try again. After you've exhausted that powder (and bullet) you can try another. It is best in experimenting to vary only one component at the time.

The short answer is buried above: Because you can't start at the top and work down! Hope that helps. Ku-dude

I do have one rifle that shows pressure signs well below the maximum load listed in one of my manuals.I actually use loads that are the suggested starting loads for this caliber and they produce velocities that match the manuals maximum load.The maximum load would definitely not be safe in my rifle.

Several months ago I worked up loads for 30-30 and .32 Win Spl using a milsurp ball powder and a particular bullet for each cartirdge. Using a chronograph and measuring group sizes it was possible to determine optimum operating pressure watching the spread. Not so oddly enough the best groups were shot when the spread was the smallest. Either could have been safely shot at much higher velocity, but accuracy started going south. "Working up" a load does not necessarily mean you're looking for maximum velocity, which often times is not maximum accuracy. sundog

Remeber, the factory has pressure barrels to check things out with.

If you're stepping on to a newly frozen lake, do you just jump on the ice, or take careful light steps at first?

In most instances, you will be using different componets then the loading manual used, different lot of powder, possibly different primers, differenct brass, and sometimes different bullets, not to mention a totally different gun.

OldFart,

The reason for this is that not all rifles are the same.

We have loaded for several hundred rifles, and although most of them are what I would consider within "normal" limits as far as loads are. There have been a few which do not seem to follow this rule.

We have had several rifles that seem to take loads which would have blown others up, and others which stick thier bolts so tight with loads that are lower than published minimum charges. I would hazard a guess these would, in all likelihoo, would have blown up with maximum charges from other rifles.

Thanks for your inputs on this, and the examples that you all have given. I suppose I'll continue to start from the bottom and work up. But I'll still have a rough time admitting that the run rag writers know what their talking about

A lot of excellent info already given... just my additional 2 cents:

I have a couple of rifles that are instrumented with strain gauges. Getting pressure information is at least as revealing as getting speed information.

There are large differences between batches of powder. Just sampling the limited stuff I have on hand, different lots seem to produce pressure differences of 2-3,000 PSI.

Different primers produce different maximum pressures, and the differences here again seem to be pretty significant. You cannot freely substitute primers.

Different brands of bullets are different. In one of my 30-06s, the maximum COL for Hornady bullets is a full .100" less than for Sierra or Speer. That leaves less room for powder.

Most of the time, you can safely load the max load, and sometimes you can make substitutions. But not always. It's those other times that get ya.

One thing I always try to keep in mind is that the load manuals are not Holy Scripture. Their data isn't written in stone or handed down from any all knowing being. The manuals are nothing more than a report of what that particular lab found.

If you do even a halfway decent search of several manuals, magazine articles and other books, you see how they don't agree on much. There's just too many variables. I give the manuals just a little more creedance than what I read on a bathroom wall. And magazines even less.

I read as many sources as I can, trying to get an idea of where and with what to start, then start low and work up as judgement and experience leads. Sometimes I end up above some manuals max loads, sometimes way below.

I came into this world with two eyes, and hope and plan to leave that way too.

Joe.

Read the A-Square loading manual "Any Shot You Want"....in it there's a great explanation on the effects of changing bullets (same weight), powder lots, primers and primer lots etc on pressure and velocity....note the higher pressure doesn't always give the higher velocity.

I buy some guns, just to take appart, see how the work, clean them, fix them, oil them, and then do a .1 gr load work up until they fail or the brass fails, save the brass in order and marked, and put the gun or what is left of it in storage.

Even a guy who blows guns up on purpose, starts low and works up .1 gr at a time.

I started out at the max load in "Lyman 45" 1970 77 gr #311252 alloy #2 4,8 gr. Unique 1111 fps S&W30 w/ 3: barrel 1.280" OAL. WSPM

The brass stuck and after 18 rounds the forcing cone blew out in a 32 Colt Pocket Positive with Liberty 32auto .311" 76 gr bullet and 4.8 gr of Unique. When I TIG welde up the forcing cone, the gun was allot stronger, so I had to buy another gun just like it to test all over again.

Now I start low.

Oldfart, back in the 60's I used to help my father reload for his .243. Knowing what I Know now and comparing it to the unscientific approach taken back then, we may be sure of living to a ripe old age using the current loading data. If I recall correctly we would fill the case with powder and back off 1/2 grain at a time until the gun stopped blowing up. This is a joke obviously, but I don't how we lived through it using some of that old reloading data from the Lyman reloading manuals. I remember many split case necks, blown primers, stuck bolts.
Today we are much smarter, we have better data, better components. I think the data is conservative and thats fine by me, especially for the new shooters and reloaders. We older guys know how to get that little extra out of our handloads should we want it.

I don't think I have any great new thing to add, but it pays to remember the great number of variables that exist in reloading. Even if you only loaded one bullet in one case, there are differences in the lot number of the bullets as made. There are differences in the primer even in the same type number, brass is different from lot to lot, and based on number of times fired. Powder can vary within the same type, from lot to lot. Now most of the time these variances do not equal a problem, but if all the variances add to a pressure situation on a bad day, well, hello Mr Murphy, how are you? I've had this happen, on what should have been low end loads, and I was fortunate to have not been damaged (never shot that particular gun again). I guess a pessismist would say "they" are just trying to cover their butts, an altruist might say "they" are trying to protect your butt, but a realist would have to say you have to cover your own butt. I personally don't drop the hammer on an untested load/gun combo without considering that. That means some degree of separation between me and the gun till I know how it shoots. But that is just me, and I wasn't always that way either.

[ 08-18-2002, 03:53: Message edited by: 8MM OR MORE ]

Most of the time you can get away with starting with a max load as listed in a reloading manuel. The emphasis here is on "most". It is those occasions that lie outside that term that make things interesting. I remember loading a .357 mag with a max load of 2400 and 180 XTPs when in a hurry to work up a load for the deer season one year. Thought I would never get the first six empties out of the chambers. The load was way too hot for my gun. So far I have not had a rifle to object to a max load as found in any of the numerous manuels I own but a buddy has a new .280 that will not take anywhere a max load as listed. The thing is you never know until you load for a particular rifle or handgun what it will accept.