Home Forums Reloading Big Game Rifles What do you think of this quote?

Mr. Jeff Olsen:
This is for me an interesting thread, by that I mean to say the pressure question.

Not having the luxury of examining your .30-30, I�d hazard a guess that perhaps it could have been a small headspace issue causing the cratered primers. Those of us who like to play with the grand old .303 British run into cratered primers as well as case stretching frequently. They often had extremely generous chambers.

One particular specimen I played with would wreck a case after 3 firings, but was a really accurate cuss so I felt it merited some time spent. After some research, I found that if I opened up the case mouth to .32 and then to .35, and then necked it back down to .312, leaving a small shoulder at the front of the case for it to headspace on, the craters and the case stretching vanished. The case required neck sizing only after that or minimum full length sizing that ensured the shoulder did not move.

Subsequently, I was able to successfully use the 2nd shoulder method on a 1901 vintage 94 in .30WCF that had a bit too much headspace, but was otherwise mechanically safe to fire. As well, I�ve since learned the 2nd shoulder works on fire-forming some wildcat cases.

Straight wall cases such as .444 Marlin and 45-70 Govt are another matter, and I have little experience thus far with straight wall cases in rifles, so I can�t comment.

Lastly, I now believe that individual barrel characteristics vary the pressures a great deal more than I used to. Some barrels are faster, some seem to build pressure faster and of course some are more accurate. Currently I have more questions than answers on that topic, but I believe it is a factor.

There has been good advice all around to use one�s head and one�s chronograph. As a warm country dweller (100�F+), I�ll add watch the ambient temperature as well!

Safe reloading and the best in the Christmas season to all.
Dwayne

Dwayne,

I don't know what was up with that 30-30. I mean, it was a good rifle (I recently traded it off, hence the past tense) but it would crater primers and the brass would only last 3 or maybe 4 rreloads tops. Major stretching, or a lot of headspace, or both. As I say, I don't really know and probably shouldn't even guess. At any rate it was hard enough for me to see what was going on that I had zero interesting in pushing things with that rifle!

That's very interesting, what you describe with that .303. How did you come up with that solution?

My "fast" rifle, the 30-06 with the pac-nor barrel, has a nice tight chamber. I effectively cannot neck size with my RCBS dies, because by the time I screw the die down to where it's just touching the case shoulder it's all the way down! Cool. Also, there's so little leade that I can barely load to SAAMI OAL specs for 30-06. Also fine with me. Finally, Pac-Nor hand laps their Supermatch barrels so that probably has something to do with it.

I have found .325 WSM to kind of maddening to load for. It's the first "new" cartridge I've messed with, and when I bought my first .325 especially there wasn't much loading data released for it yet. There was a little more wingin' it than I was comfortable with. It's better now but still the data is sketchy compared to old favorites.

-jeff

Jeff:
Regarding the question as to where I came up with the solution to the .303 cases stretching, I know I read it somewhere. While it might have been some PO Ackley articles, it could have just as easily been an Edward Matunas or even a Rick Jamison article. I can�t exactly remember, sorry. Firearms of all sorts have been a lifelong passion of mine, so I try to read as much literature on the subject as I can lay hands on.

We�ve actually used the 2nd shoulder in a Parker Hale .300WM that had a too-long shoulder and was splitting cases on the 2nd reload. I believe it should work with any case which headspaces on the rim or in the case of the .300WM, the belt.

So far I have reloaded for about 2 dozen or so different cartridges, a path I started down in 1981. At the time, I wanted to shoot a rifle for which ammunition was not available, another 94 in .38-55. I traded the .38-55 for a .22 revolver before I got dies, but I�d already begun loading for the .308 and .30-06. The rest is, well you know�..

It�s been surely an education for me, although I have more questions now than I did when I started out. I believe that if my wife had not given me that Chrony long ago I could have continued on in my unknowing bliss���.

All the best to you and yours in the Christmas season Jeff.
Dwayne

From Jaywalker
�and I'm certain there's a cushion. That doesn't mean, however, that the cushion is there for us to use - it's like a safety margin on structural steel that's there in case of accidental overstress. �
I have to agree with Jaywalker� While I am not certain there is ALWAYS a cushion, I do believe that if one exist it is there to cover variables.
Variables like differences between powder and primer lots, chamber and ambient temperature and the like.

If you are too close to the edge it only takes one problem to have a real bad day� and convence others that we handloaders are idiots.

As Outcast said �If your .270 doesn't go fast enuff for you get a .270WM�.

I would think that cushion is more like the 'bell curve' method. The vast majority of rifles made to SAAMI specs and even custom chambers should fall within the bell curve. Of course when you look at the bell curve there are flares on both ends which should be the rare exception of rifles that will be overpressure on minimal loads and those that will be underpressure with maximum loads. Those that are underpressure with max loads can safely exceed the charges that are listed in the manuals. How do you know you have one of those rifles? That is where a healthy dose of moxy helps and good reloading practices. I think the ancient loads like the 30-06 has the bell curve intentionally shifted left to fit many more rifles for safety. New wiz bang loads like the WSM has a rightward shift as they are designed to fit in a tight bell curve and all rifles chambered for it will be able to handle the "modern" pressures.

The problem comes when there is no margin in your rifle.

I've had to stop below book maximum many times, so generally, I believe them. That's not to say that it works out that way all the time. I have at least two well used favorite loads that are above book max for the components (about .5-.75 gr over) and two favorite loads that are well under book max (1-2 grs), but are max in my guns. Without pressure testing equipment this is all pretty tricky. I use the chronograph and watch the case life, stretch, and primers, and, like most people, do the best I can. Even when I do go over book max, I don't go far over.

Hey... speaking of this stuff, I have a load I'm working on right now and data is pretty thin. Or at least I haven't found any. So I'm extrapolating from other close loads and working up. Anyway, it's using a 8mm 180-gn TSX in a .325 WSM (in case anyone has anything) but my question is, is it possible to call Barnes for info about their stuff? The old Barnes book is pretty useless with the grooved TSX. And Nosler and Speer don't mention them of course. Hodgon does mention Barnes bullets, but, only the old X Bullet. Anyway, any thoughts are appreciated.

I'll call Barnes but I'm wondering what kind of reception to expect!


-jeff

Jeff, Google is a good thing.

http://www.gunsandammomag.com/reloads/0607/

http://www.barnesbullets.com/information/load-data/tsx-guidelines/

That's the spirit!


Casey

That is pretty close to my thinking too, Supercrewd........



Casey

Thanks for the links, Supercrewd. I'd read that stuff on the Barnes site before; problem is they've pulled all their X-bullet load data, I *think*, so it's not that helpful. I don't have a Barnes book. The Handloader article is something I've printed out but I don't use those powders... I know, I know... but H4350 gives me good speed and accuracy, dang it!

Barnes listed 67 grains as a max for the 200-X bullet and that does great for me with the TSX. It would seem that, with a lighter bullet, I should be able to use a little more with the TSX. We'll see... very sloooowly.

-jeff

martinbns:
I reckon that, too much to drink, is never enough.
Smitty of the North

Striving for the last iota of velocity from a cartridge when you are literally shooting in the dark with pressures is a horrible cost to benefit model.

As has already been said, the problem with reloading is that you don't really know what pressures your loads are generating. You can have a "good idea" what they are. Cross referencing several sources of pressure tested data and measuring velocities with a good chronograph can give us a fair estimate if you use the exact same components as the sources, but unless you have pressure testing equipment for your individual rifle, you cannot know exactly. Even pressure testing equipment readings will vary with the installer and reader.

And just what do you really get with "max" loads (having no idea exactly when you've hit or exceeded a maximum lifetime usable pressure in your individual firearm)? An inch flatter trajectory at 400 yards? Another 100 ft/lbs of energy?

What do you risk? Your rifle and scope, your eyes, your hands, your life? I don't think Wind in His Hair would call that a "good trade".

A neat axiom of the energy/velocity relationship is that at the top end a 50 fps mv gain might increase your pressure by 10,000 psi. The converse is that you can lose perhaps 10,000 psi of pressure and only lose 50-75 fps, a very beneficial ratio in my mind. Obviously 50 fps and 10,000 psi are not exact numbers and vary with rifle to rifle but the important thing is that a minor velocity gain will cost you more pressure increase than you might think.

Again, just what does it cost you to strive for that last 50 fps vs. what you actually gain (little) when you have no real idea of just how close to that "last 50 fps" you are, or were?

Jim, is that not what they refer to as cartridge efficiency? (I am stating the obvious, not critiquing).

To take this discussion to a different plane, if you take the speed past the best accuracy (I usually find my most accurate load less than the published max), what do you gain from the additional speed? Say your best load shoots 0.5 inches at 100 yards. Extrapolating that group to 400 yards should theoretically yeild you a 2 inch group. Pretty respectable if you can shoot that well. Now crank up the velocity to the published max and the bullet now flies xxx inches flatter at 400 yards. This new faster load shoots 1 inch at 100 yards, yeilding you a 4 inch group at 400 yards. Still pretty good shooting if you can do it. The question is: Have you improved the ballistics enough to overcome the inherent 2 inch group size difference? Most likely not. The joy I get out of handloading is not building the fastest cartridge that I can muster, it is the most accurate. In my mind that accuracy builds confidence in my platform and allows me the best opportunity to make a shot.

Jeff, you really need some RL15.

Have seen various definitions of efficiency - foot pounds of energy per unit of powder used is one. By that score the .22 Short is probably the most efficient cartridge around.

My point was that in most endeavors risk is weighed against potential gain. The bigger the risk, the bigger potential gain there should be. Who would bet $10,000 with a 50% chance of losing it all vs. a 50% chance of making a 1% profit? Amount of risk is up to the individual, but a smart person quantifies the risk as much as possible.

In handloading, we can't quantify that risk with a whole lot of accuracy. We can know "probably close to the edge", "probably not too close", "really likely not too close", but that's it. And even if we have a good handle on "close" we have no idea of how many cumulative "closes" the rifle can manage before it says "you went too far" (really loudly). But if we stay in the "very probably not too close" range we can be "really, really, really probably" assured we'll never exceed the cumulative firing limits at that level.

And what are we risking - our health, that's what. Even if the actual odds are really low - suppose there's a .8% chance you'll seriously exceed your rifle's max pressure limitations and lose your eye if you go over a book max load by 1.5 grains. Combine that with a .04% probability that you have already exceeded your rifle's limits if you only load to the book max. But what do you gain by even taking that chance? Nada.

But I like the opposite - you can significantly reduce the probability that you're exceeding your rifle's individual limits at or 1-2 grains below book max and the only loss you take is 50 fps of velocity.

It's just a personal philosophy. If someone wants to bet fingers, eyes or other body parts against an inch of trajectory that is completely up to them. But I didn't manage to stay as good lookin' as I am by gambling on completely unnecessary risks.

NICE post Jim.

-jeff

Jim, no arguement from me, well said.

Margin in what manner? Margin between hitting the max sammi load or margin with which you gun blows up?

I have read many times that if your showing the traditional signs of pressure such as case head expansion, stiff bolt lift etc, you are way over max, pushing the realm of 80,000cup or more.

I believe in getting the full velocity out of a case but when I reach accepted speeds I stop where I am if accuracy is acceptable. If I see pressure signs I drop at least a full grain and tweak oal from there. I get full speed out of my .308 but if I wanted a 30-06 I would have bought one.

Why does someone feel the need to post a response like this??

if you don't like the subject, or the post's author, then pass it by...

Why does one feel the need to think the rest of us need your negative opinion as part of the subject or thread???

History.