determining accurate loading data
I'm sure this general issue has been dealt with here before, but without indexed archives I don't believe I want to attempt to retrieve the relevant threads.
There are discrepancies between my manuals; mostly, I believe, because Lyman used 4" test barrels for virtually all rimmed revolver cartridges. Consequently the velocities don't jive with those in my other manual, whose compilers used an 8" barrel. Is there such a thing as a conversion table for this? If not, how is a fellow to determine(without buying a chronograph and a bunch of different powders) actual results with any degree of accuracy? More importantly, will pressures differ to a similar degree as do velocities?? If so, how will one know what is safe?
As always, thanks again for the assistance.
There are discrepancies between my manuals; mostly, I believe, because Lyman used 4" test barrels for virtually all rimmed revolver cartridges. Consequently the velocities don't jive with those in my other manual, whose compilers used an 8" barrel. Is there such a thing as a conversion table for this? If not, how is a fellow to determine(without buying a chronograph and a bunch of different powders) actual results with any degree of accuracy? More importantly, will pressures differ to a similar degree as do velocities?? If so, how will one know what is safe?
As always, thanks again for the assistance.
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THE ANSWER IS, THERE ISN'T.. WITH OUT THE CRONIE...YOU WILL NOT KNOW. AS EACH GUN WILL NOT BE EXACTLLY THE SAME, LET ALONE DIFFERENT MANFACTURES, BBL LENGTH, ETC, ETC. THE MOST IMPORTANT THING IS ALL MANUALS START WITH A SUGGESTED STARTING LOAD & GO TO MAX LOAD. AND THE MOST MOST IMPORTANT IS THE LOAD THAT SHOOTS THE BEST GROUP & YOUR GUN FUNCTIONS EVERY TIME!!!!!!! NOT, NOT! HOW FAST IT GETS THERE!!!!IF IT GOES 800FPS & HITS THE SAME PLACE EVER TIME, OR GOES 10,000 FPS & HITS NOTHING, WHATS THE POINT!!! NOTHING I EVER SHOT, KNEW HOW FAST THE BULLET WAS GOING. THEY ALL DIED. 0 -
Mr. fergusonmorse:
Relax, sir; I hear you.
Now, correct me if I'm wrong; but I was under the impression that velocities matter a great deal when one is considering home defense rounds. Too fast = too much penetration and therefore a hazard to those on the other side of walls, and possibly less effective in stopping the attacker, depending on some other variables. Am I close to sound thinking thus far? If so, when loading practice rounds, we're supposed to come as close as possible to the velocities of our chosen factory rounds(I know that one should practice with some of these; but I rather doubt if very many people have the means to practice exclusively with factory loads.) in order to attain similar recoil, report, etc. as the actual factory defense load. Would not the velocity figures in the manuals become important in this situation? And would not the discrepancies become problematic, at least to some extent?
I also notice some pronounced differences in listed pressures between the manuals, with the same components and powder weights. Furthermore, in some cases both starting and max. loads differ rather markedly between manuals, again with the same components. I would like to hear these matters addressed.0 -
BWA: First, any handload worth while using for "home defence" certainly will penetrate most walls if you miss. Unless you hit
a thick portion of the body, depending on your slug and velocity
(not exceding 900 fps) should stay in a perp. Sounds like a box
of Glasser type cartridges are your best bet for stopping power and less
wall penitration. You did not mention the calibre you are concerned
with and that would really help and make a big difference for someone
to help you.0 -
joe: Home defense isn't the primary issue here; I just used it as a prominent example of why differing velocities might matter(since fergusonmorse didn't think they mattered). My concern is how to reconcile conflicting loading data so that one has some rough idea, when he is finished loading, what he can expect from the cartridge. And my biggest concern, which remains unaddressed, is what to do when listed pressures, starting loads, and maximum loads differ between manuals, when the components are the same. How does one know which manual is correct? 0 -
GUIDES!!!PLEASE REREAD MY POST, YOU ARE ASSUMING ALL COMPONENTS ARE THE SAME, BETWEEN THE MANUALS, THEY ARE NOT! AS EACH MANUAL IS PUSHING THERE PRODUCT, THE FOLLOWING IS TRUE, PRESSURE & VELOCITY CHANGE WITH EACH THING THAT IS CHANGED, I.E., PRIMER(LOT&MANUFACTURE), POWDER(LOT), CASE (MANUFACTURE & LOT), BULLET SEATING (OAL), BULLET TYPE(MANUFACTURE,LEAD,JACKETED, COATED, SHAPE, WEIGHT,ECT), BARREL (MANUFACTURE, LENGTH, CHAMBER,).. NOSLER MANUAL THERE BULLETS..HORNADY THERE BULLETS, CASES....SPEER THERE BULLETS, PRIMERS,CASES... HODGDON IS GENERIC ON BULLETS, THERE POWDER, & SOME OTHERS, LYMAN, THERE CAST BULLETS, WITH THERE LEAD MIX & LUB, READ CLOSE, JACKETED BULLETS BY MANUFACTURE, & PRIMER,.... ALSO EACH MANUAL USES DIFFERENT ACTIONS, BARRELS LENGTHS, TEST...THEY ARE ALL GUIDES NOTHING MORE!!! WHY WORRY ABOUT FACTORY DUPLICATION... REREAD MY OTHER POST...ACCURACY & FUNCTION ABOVE ALL ELSE, WITH OUT IT, WHY BOTHER. 0 -
GUIDES, GUIDES, GUIDES... LETS ASSUME YOU START WITH A GOOD QUALITY FIREARM, IN GOOD CONDITION, CLEAN, IN A POPULAR CALIBER.. YOU HAVE A FEW MANUALS, YOU WANT TO LOAD, TO SAVE MONEY, SHOOT MORE, YOU HAVE TRIED FACTORY;.. YOU MUST DO THIS SAFELY, YOU MUST READ ALL THE CHAPTERS IN YOUR MANUALS, (CHAPTER ON PRESSURES(SIGNS, ETC) & YOU USE ALL THE EXACT!!! COMPONENTS,.... BRASS, PRIMERS, BULLET, POWDER, STARTING LOAD!, WITH THE PROPER OAL.. SAFELY, CHECKED & DOUBLE CHECKED.. GO TO THE RANGE & IT WILL SHOOT WITH OUT EXCESS PRESSURE. IT'S WHEN YOU START TO CHANGE THINGS, THAT YOU MUST BE VARY CAREFULL, ABOUT. WHEN YOU EXPECT YOUR HANDLOADS TO HAVE SIMILAR RECOIL, REPORT, VELOCITY, OR MORE, EXPECT PRESSURES TO RAISE VERY HIGH, VERY FAST, GO SLOW FROM STARTING LOADS, WHEN CHANGING COMPONENTS OR OAL, RETURN TO STARTING LOAD, WORKING UP. LOOKING FOR PRESSURE SIGNS.(READ THE CHAPTER) WHEN YOU FIND THE MOST ACCURATE LOAD THAT FUNCTIONS EVERY TIME, WITHIN PRESSURE LIMITS OF THAT GUN, STOP, WHY GO FURTHER. YOU HAVE THE BEST!!! IF YOU MUST KNOW IS SPEED GET A CRON, IF YOU MUST MUST KNOW THE PRESSURE YOU CAN SEND SOME LOADED ROUNDS TO A TEST FACILITY. THE POINT ONCE AGAIN ACCURACY & FUNCTION ='S THE BEST COMBINATION, ITS NOT THE REPORT, SIMILAR RECOIL, OR VELOCITY TO SO CALLED NORM. 0 -
OK, ferguson, now we might be getting somewhere. Your next-to-the-last post enlightened me about all the variables involved. If I'm understanding you correctly, this is why the manuals are merely guides; nothing more. But if that is true, why then are the people behind the data insisting that we follow it to the letter? If something is merely a guide, why is it treated as a Bible? Even more puzzling to me is why each manual insists that its data be followed precisely, when its data differs from the others. Whose infallible and inviolable data shall we choose? Furthermore, how is it even possible to match each component exactly? Your own posts tell me it is not, since you say that pressures vary even with such things as the LOTS of primers, powders, and cases; also with differing barrels and chambers. Obviously no reloader can duplicate every one of these things.
Your emphasis on accuracy and function would generally apply, but not always. Again I would use defense as an example. Function would still apply if one uses a semi-auto; but in a revolver all that has to happen is for the powder to ignite and the bullet take off fast enough to incapacitate the threat. A wide variety of loads will do that much. And how finely-tuned must accuracy be, at 5-15 feet? It's simply not the major issue. Is not the major issue to concoct a practice load which behaves like the factory round we've chosen to carry, so that we won't be surprised under the severe stress of a defensive situation by heavier or lighter recoil, louder report, etc. -anything which throws off the technique we've carefully cultivated so as to HIT and therefore stop the threat?0 -
bwa, I see lots of confusion here (and a potential for harm) so let me address the issues one at a time.
First, you asked quote:what to do when listed pressures, starting loads, and maximum loads differ between manuals, when the components are the same. How does one know which manual is correct?well, to start with, the components are NOT the same. Each manual was written with a different lot of powder, different lots (and often brands) of primers and brass. All of these will affect internal ballistics and either increase or decrease pressure. This is why every reloading manual tells you NOT to start out at maximum loads, start at least 10% below and work up to max. Next - quote:Now, correct me if I'm wrong; but I was under the impression that velocities matter a great deal when one is considering home defense rounds. Too fast = too much penetration and therefore a hazard to those on the other side of walls, and possibly less effective in stopping the attacker, depending on some other variables. OK, you are wrong (in part). There are 3 key factors (OK 4 but who's counting) in determining a home defense round. 1-Bullet construction - you want an expanding round that will inflict the maximum amount of tissue damage. 2-accuracy (including your ability to handle the loading,) as an example, while a .577 T-Rex will inflict a LOT of tissue damage, it might intimidate the user to the point he misses!! 3 - Muzzle velocity, not so much as a concern for over-penetration but rather a concern that it be fast enough to allow for expansion (see #1 above) and 4- user confidence which includes acceptable answers to 1, 2 and 3 above as well as a personal belief in the round. Lastly, you said quote:If so, when loading practice rounds, we're supposed to come as close as possible to the velocities of our chosen factory rounds(I know that one should practice with some of these; but I rather doubt if very many people have the means to practice exclusively with factory loads.) in order to attain similar recoil, report, etc. as the actual factory defense load. who ever told you this? You need to shoot enough of your selected defense loading to understand its performance (recoil, point of impact, report, etc.) but for practice - go to a lighter loading that will not induce flinch/twitch/jerk-the-trigger-with your-eyes-closed bad habits. Your practice should focus on training muscle memory so that under stress you can squeeze the trigger and hold a good sight picture because it is second nature. Believe me, if you ever need to use your defensive load for real, you will not worry about (or even notice) recoil etc..
I hope that this is helpful,
Quod principi placuit legis habet vigorem.Semper Fidelis0 -
I have this solved by using having about 8 manuals and sources
I have picked up over the years. They are usually in the same
ball park and the figures that are most common is where I start.
I just load to try for about 900 fps. Make 5 or 10 rounds of each test load and see how they group, and look for any signs of overpressure.
Over pressure can be a very flat primer, escaping pressure around the primer, impressed image of the bolt on the rear of the cartridge, expanded or strained metal on the cartridge, and probably some others that another person will remember. The high loads are never needed.
because I only load for practice lead. About 900 fps will get a good
group and function my autos just fine. My forty caliber auto
requires factory crimp in order to chamber consistently. None
of the others do.
Lastly, my Concealed carry teacher said that you never use
your own loads for defense. An attorney will claim you load
your own, because you want to hurt people and are just hoping
to get to shoot someone. Factory loads protect you against that
claim. Buy the best and most effective but practice with your
home loads. All you do with factory is test them for performance
and dependability.
There are also other factors. Like, you always say you
shot to "stop" the assailant and "you were in fear of your life".
Those are the only right answers to avoid prosecution in our
liberal courts.
Eric
thats'me0
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