However I've seen over max loads posted at various internet forums, in Rifle and Handloader, and various other places that usually have knowledgable info. (Don't worry- I'm not going to try out loads from unconfirmed sources- like some guy that just popped up on the internet)
Basically, I presume that the staff at "Handloader" have acess to Nosler manuals, so why are they exceeding the max load for a .270 with a 150gr Partition? (I just chose .270/nosler arbitrarily)
Usually when I'm working up a load, if I get to max, then I play with seating depth etc. But there is often LOTS of room left in the case, especially if the bullet doesn't need to be seated too deeply.
If I get good accuracy, with no pressure signs, I'm usually happy. What do you do? Do you strive to fill the cases up to 95% or do you not care?
When you get the usual pressure signs after firing a load, you can bet you have exceeded the same SAAMI pressures for that case. Conversely, you can exceed SAAMI maximums and show no pressure signs. It's always best to stay within the safe velocities and pressures published for that particular cartridge.
Much of the reason loads are thought to be conservative today compared to the past is that our pressure measuring equipment is significantly better today. Litigation does enter into it but all that does is make everyone a bit more cautious and safer.
Don't exceed maximum published loads without some form of testing equipment. With a chronograph, don't exceed maximum published velocites. Best to be safe than sorry and those extra 100fps won't make a bit of difference on game if you hit where you aim.
As nearly as I can figure this thing out, the effect of going over the published limit is not sudden, catastrophic failure of the gun. It is greatly decreased firearm life.
There is a general rule of thumb in this type of situation that as the applied stress goes up linearly, life decreases exponentially.
Pressure signs generally do not show up until you are far past the SAAMI specs.
For example, in the Speer #13 Manual for a 150gr 308Win Load, if I just picked the top Load shown for RL-15, it would have been too high for mine. My Lot of RL-15 is simply faster than their Lot. But, using the WW748, (in my current 308Win) it is possible to exceed their listed Load with "some bullets" but not with others.
I completely agree with you that using someone elses Load information from ANYWHERE other than one of the actual Component Manufactures Manuals is just not something I'd do. And as just said, even using the actual Component Manufacturers Manuals, you still need to "develop from below".
No argument with Bob338's method at all, it works well for him and lots of folks. I prefer to use actual Expansion measurements from both the Casehead and Pressure Ring to know when I've reached a SAFE MAX Load level.
About the only people I've seen write about it during the past 45 years are Bob Hagel, Ken Waters and a brief mention of Casehead Expansion in each Speer Manual.
I like Case Expansion measurements because you are getting information "directly from" the weakest link - the actual Case. You do need a set of Micrometers with 0.0001" capability (0.001" capable Calipers are just not accurate enough), but this very old method still works great today.
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Good hunting and clean 1-shot kills, Hot Core
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Jay
"For God and Country"
Many of my loads are a grain or two over book max and have been for years. My old books show the same dispersion...
It is your call and depends on your actual reloading knowledge and experience but in my opinnion most loads can be exceeded and most of the folks in the know do it...Rifles vary to such a great degree in which loads they will take that one has to work up what the individual rifle will take.
I only speak for myself and not for anyone else, as I have been reloading for near 50 years or more and I know what I'm doing, how to mike cases etc. and that does make a difference........When one is a reloader he is on his own and his mistakes are his alone.
Even the loading books vary by several grains....Start low and work up when you get near max the velocity increases will normally drop to 15 to 30 FPS per grain of added powder..so cut back a grain at that and your brass will last longer and that increase is not worth the trouble.. You may or may not be over book max at this point....
Case life is a good indicator of your max load..
I recommend new reloaders stay under max until they are 99% proficient at the bench..The learning period is where the bad stuff happens, but not allways...I have never blown a gun but I have popped out a few primers and had one gas leak but that was a 243 and not a hot load..They have a habit of that when throat wear starts, but thats another subject....
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Ray Atkinson
Work up loads that are safe in your firearms and never give a friend a handfull of your ammo to try in their guns if your ammo is anywhere above a mid-range load. You probably shouldn't give anybody your handloads anyway, unless they are going to test them in a pressure barrel.
I will make one exception. The max loads listed in my Speer manual for my 6.5X55 Swede are pathetic, they don't even expand the case. I now use a max load published by Lyman that equals Norma factory stuff.
[This message has been edited by John Y Cannuck (edited 08-29-2001).]
IIRC one went from flattened primer, to pierced primer, to jammed bolt, to a complete blowup in successive one-grain increases.
Any manual uses one firearm, whether a conventional rifle, or a switch-barrel pressure gun, to work up its published loads. The maximum they list is the maximun they recommend in that PARTICULAR gun (with perhaps a safety margin). EACH rifle is a rule unto itself, and will likely give a different pressure and velocity with a given load than any other rifle. Variables such as chamber dimensions, bore size, rifling type, bore finish, etc., make it impossible to predict the exact "maximum" for any one gun.
Maximum also relates to what it is that you wish to achieve. Do you just want one firing from a case? If so, your "maximum" will be several thousand PSI above the "maximum" of someone who wants indefinate case life.
Do you want slick action operation and easy reloading? If so, then your "maximum" is less than if you don't care if you have to hammer the bolt open with each shot.
I'll swear, I've known shooters who claimed that Manual X was "better" than Manual "Y" because "X" listed two more grains of 4350 and 50 FPS more velocity as "maximum" compared to "Y".
I have a .270 which won't start to digest the time-honored charge of 60 grains of 4831 behind a 130 grain bullet for 3140 FPS without unreasonable pressure signs, but gives 3200 FPS with only 58.5 grains of powder. So why should I complain?
On the other hand, one of my .223's needs almost 8% more H335 than usually recommended to achieve normal pressure and velocity.
"Maxumum" is whatever works in YOUR INDIVIDUAL RIFLE.