Who's playing it safe/Being reckless?

[planetsmasher]

I am fairly new to reloading, but I pay very close attention to the data in the manuals, and always stop a little short of the max loads of powder advised. However, I have noticed that in a lot of cases for the same bullet/powder combination.. the bullet manufacturer and the powder manufactures data have some pretty wide discrepencies. For example.. I am reloading .303 British with Sierra 150 prohunters and 174 hpbt, with Varget in new Remington Brass. The Hodgson data shows a max load in both cases that is over 2 entire grains more than the Sierra data shows?!

Whos info would you consider more valid...and for what reasons? Thanks.

[Dick284]

I follow my chrony, and case life. Remember even the test barrels used in load development differ in dimension and manufacture. Manuals mean nothing to me other than a guide line for what to use and where to start, the individual rifle will dictate where max pressures are (speed and case life)
Example is Abwhitetail, his 7-08 peaks out before reaching any published load for a given powder. The chrony says that his load 1.5grs. less than primer leaking, are giving velocities bang on gfor his bullet, and barrel lenght, that is his max load, not mine, not yours, but his(actually the rifles).
Get what I mean.

[catnthehat]

Both are valid for THEIR test equipment they used!
There are so many variables, that one cannot arbitrarily say that one manual is right and one wrong.

Different lots of powdrs, bullets, chmaber differences, sea level , ambiamet temperature, even the chronographs and strain guages used all come into play.
That is why it is always stated to start 10% lower and work up your charge...
Cat

[planetsmasher]

Yeah, I see what you mean Dick. The info given is ballpark, and if I am wise, I start with the lower of the given datas and work up. No harm done if I find that I have limp loads.. I can always keep creeping it up and watching for pressure signs. I don't have a chrono.. so I will have to look for some other tell tell indicators that the load is working well. I have read that by the time you notice a sticky bolt on opening, that you've gone too far already. I didn't know what to make of that.. I mean, I would agree that's a sign to STOP, but I don't know what they meant by "gone too far" if you haven't done damage to your rifle or yourself.

What do you find is the first sign you see that your load is too hot?

p.s. is Dreadful Valley on the banks of the mighty North Saskatchewan by chance?

[planetsmasher]

Thanks Cat.. I've heard it before but I guess I thought if I ask in a different way I'd get an easier answer! Hahahaha.

[catnthehat]

Originally Posted by planetsmasher

Yeah, I see what you mean Dick. The info given is ballpark, and if I am wise, I start with the lower of the given datas and work up. No harm done if I find that I have limp loads.. I can always keep creeping it up and watching for pressure signs. I don't have a chrono.. so I will have to look for some other tell tell indicators that the load is working well. I have read that by the time you notice a sticky bolt on opening, that you've gone too far already. I didn't know what to make of that.. I mean, I would agree that's a sign to STOP, but I don't know what they meant by "gone too far" if you haven't done damage to your rifle or yourself.

What do you find is the first sign you see that your load is too hot?

p.s. is Dreadful Valley on the banks of the mighty North Saskatchewan by chance?

Usually the first sign of pressure is tight bolt lift and flattened primers.
however, this is not always the case.
Some combinations look good and then BOOM!!
Stuff comes apart, primers fall out ( or are missing altogether!), and other bad stuff.

There are also times when some shoters disregard the flattend primer thing, and wind up the loads , but those that do generally have over built actions capable of twice the pressure a particular cartridge can generate.

This has always been a controversiall topic howver, and I shall not dwell on it.
Cat

[Dick284]

Yes DV is on the N.Sask.River
Sticky bolt lift and flat primers usually occur somewhere in the 15 to 20% over max design pressures for many combinations they are observed in.
think of it this way, if the SAAMI max design pressure for a caliber is 60,000PSI and you dont see pressure signs till 15% over your likely running pressures of about 69,000psi.
Most proof loads for the various actions are about 70,000 to 75,000psi, and that happens to the action once. Guess what happens 100 or 1000 rounds down the road! Maybe nothing if your a lucky SOB, but maybe you will have a nasty run in with a phenominum called "Cumulative Metal Fatigue".
That's why a chrony and case life, tell you more than a sticky bolt lift, if the caliber bullet combo is only designed to do at best 2800fps, and your getting velocities of 3000fps, (barrel length, plays a role of course) your on a road to possible ruin.

[ABwhitetail]

After doing some extensive load development, well I shouldn't say "after" because I am currently still int he process of it.....as Dick284 said, I am seeing pressure signs (with varget) at 1.5-2 grains lower than published numbers...

From what I am learning of load development, it is a combination of SO MANY factors that are going to determine what you're rifle is going to like and tolerate...

I guess that is why the first thing ALL these experienced gun guys tell you is EVERY GUN IS DIFFERENT!!!!

If a guy is serious about load development for a particular rifle, my experience with Dick284's chrono on the weekend tells me that this is such a VALUABLE TOOL it really should be something a guy puts in his arsenal....

In my case, my loads of 41 grains of varget where reaching speeds that matched the max numbers in the manual....so I knew I was at the point where I probably wasn't going to get much more out of it....that is also where I seen my best groups....with a combination of info from the holes in the paper and chrono numbers I know that I'm at about the max for Varget....in MY gun....

[planetsmasher]

Hmmm.. ok, that's certainly food for thought. So now, is a chrono something you can get at a normal gun shop.. or is it something they would have to order in? And that opens up the whole " whats a good brand that wont put me in the poor house" can of worms.

I'll google.

[planetsmasher]

Ahhh never mind actually... I scrolled down and saw a thread that basically covers the same ground.

Thanks a bunch to all repliers.