I don't get it about the various load data

[BubbaJon]

BubbaJon They ain't no easy answers...you already got some great responses, I give up and through this at ya. Manuals have been lowering charges over the years. I talked to Tom at Hodgkins and he said they hold strict standards to burn rate.
You will here about different burn rates between new and old (he said the is old military stuff) He said since the 70's there is no dangerous variations in burn rate...

Lee was saying pretty much the same thing in his "Classic reloading". He says that for a while "velocity sells" and the powder vendors were publishing pretty hot loads. He insinuates there were "incidents" and with modern liability lawyers pounding the bushes and the 2nd Amendment under attack they decided they better cool it. so now the published loads are less.
He made a very interesting case for determining the optimum charge for cast bullets that depends on knowing the hardness. He points out that hardness can be translated directly to PSI by virtue of the fact permanent deformation is inflicted by pressure. The fact the deformation is permanent means the ultimate tensile strength was exceeded - IOW the pressure from which the material cannot regain it's shape after being deformed. His theory is that the best chamber pressure is with 10% of the pressure required to permanently deform the boolit - multiply the boolit Brinell hardness by 1422 to get the optimum pressure in PSI. So for my Dardas cast boolits that would be 22,752 with their published hardness of 16. His theory was tested with Hodgdon and verified. Basically that pressure will allow teh boolit to deform and seal properly but regain its shape so the path is not altered by a distorted boolit. So I should be looking for a load that produces a pressure of around 22-23 thousand PSI - problem being dang few publish pressure data.

[me]

Lee was saying pretty much the same thing in his "Classic reloading". He says that for a while "velocity sells" and the powder vendors were publishing pretty hot loads. He insinuates there were "incidents" and with modern liability lawyers pounding the bushes and the 2nd Amendment under attack they decided they better cool it. so now the published loads are less.
He made a very interesting case for determining the optimum charge for cast bullets that depends on knowing the hardness. He points out that hardness can be translated directly to PSI by virtue of the fact permanent deformation is inflicted by pressure. The fact the deformation is permanent means the ultimate tensile strength was exceeded - IOW the pressure from which the material cannot regain it's shape after being deformed. His theory is that the best chamber pressure is with 10% of the pressure required to permanently deform the boolit - multiply the boolit Brinell hardness by 1422 to get the optimum pressure in PSI. So for my Dardas cast boolits that would be 22,752 with their published hardness of 16. His theory was tested with Hodgdon and verified. Basically that pressure will allow teh boolit to deform and seal properly but regain its shape so the path is not altered by a distorted boolit. So I should be looking for a load that produces a pressure of around 22-23 thousand PSI - problem being dang few publish pressure data.

+1 BubbaJon.... but telling reloaders about Lee's theories just feeds the insatiable need to know I just need more toys and time and $$$$

And I'm sure just like the muscle cars of the 60-70's the books were cooked to look gooder than the other guys. (course didn't they down play HP on a few cars to stay in compliance)

[miatakix]

Hmm, yeah, my Speer manual has the separate sections for rifles and handguns for .44mag, but does not mention T/C actions anywhere. Interesting. Another variable you'll run into when comparing loads across manuals is the seating depth. Of course when an equivalent bullet is seated deeper into a case there is less initial internal cartridge volume, so one cannot use as much powder, and vice versa. I noticed a pretty big difference there across my manuals for .45 Auto.

[BubbaJon]

Another variable you'll run into when comparing loads across manuals is the seating depth.

I just seat 'em to where they need to be seated - it's pretty obvious on both my bullets. The Hornady has a cannelure and the Dardas based on Keith's design has a definite "shelf" to part the lip against. I figure I already sized the cases for length so whatever pops out *has* to be right. So far so good...

[Gohon]

Hmm, yeah, my Speer manual has the separate sections for rifles and handguns for .44mag, but does not mention T/C actions anywhere. Interesting.

I would think there is no need for the mention as 44 Magnum guns are designed to work at very high pressures. If your Speer book is #13, go to pages 530 & 531 for the 357 magnum and you'll find a warning that the loads on that page are for use in single shot pistols only with the T/C being used as the test gun. It doesn't mention Ruger or Freedom Arms but other manuals sometimes do.

Basically that pressure will allow teh boolit to deform and seal properly but regain its shape so the path is not altered by a distorted boolit.

I don't understand this........I've always thought lead has no spring back ability such as brass does. Once lead is shaped, whether by being deformed or by other means, it stays at that shape. This is one of the problems sometimes presented by the Lee carbide crimp die. The carbide ring swages down the brass and bullet but the brass has some spring back and will almost return to it's original diameter, where as the bullet will not. This results in a slightly looser fit of the bullet in the brass. What am I missing?

[BubbaJon]

I don't understand this........I've always thought lead has no spring back ability such as brass does. Once lead is shaped, whether by being deformed or by other means, it stays at that shape. This is one of the problems sometimes presented by the Lee carbide crimp die. The carbide ring swages down the brass and bullet but the brass has some spring back and will almost return to it's original diameter, where as the bullet will not. This results in a slightly looser fit of the bullet in the brass. What am I missing?

All materials have an inherent modulus of elasticity - lead is as you would expect a lot less than brass, about 7-8 times less approximately. So it's normal for the brass to spring back somewhat - but if it's loose then something ain't right. Perhaps you're expanding the neck too far?
I have no problems with my Lee Factory Crimp - works awesome and I highly recommend it.

[Gohon]

All materials have an inherent modulus of elasticity - lead is as you would expect a lot less than brass, about 7-8 times less approximately. So it's normal for the brass to spring back somewhat - but if it's loose then something ain't right. Perhaps you're expanding the neck too far? I have no problems with my Lee Factory Crimp - works awesome and I highly recommend it.

Elasticity yes......ability to spring back, no. If lead had any memory at all for spring back then one could never swage a bullet and expect it to come out of the swage die. You can reshape lead such as running it through a sizing die but you cannot compress it.

I have no problems with any of my Lee crimp dies. I use them on everything I reload. I removed the carbide ring in the 38/357 and 45 Colt dies just to keep from swaging down my over sized casts. Ranchdog sells special Lee collect crimp dies without the carbide ring just to prevent this very problem. I assure you if you are using a Lee carbide crimp die and your bullet is over factory specs, then the die is sizing down your bullet and the case no longer has the same grip as when you first inserted the bullet. I'm not talking about so loose that one can spin the bullet....the amount is very minute, but the grip has certainly been lessened compared to when you first sized the case.

[miatakix]

I just seat 'em to where they need to be seated - it's pretty obvious on both my bullets. The Hornady has a cannelure and the Dardas based on Keith's design has a definite "shelf" to part the lip against. I figure I already sized the cases for length so whatever pops out *has* to be right. So far so good...

Yeah, that sounds good. I've heard of people ignoring the cannelure, but not so much for heavy recoiling revolvers or lever guns. I guess the calibers I focus most of my reloading on are a little different...most of my .45 Auto bullets have no cannelure, same for a lot of the match bullets for the .223 and .30-06. In the lever guns I haven't really gotten into lead bullets much, yet, although plan on doing that soon (just need some alloy then I'll be all set).

[rimrock]

Load data in the manuals has drifted downward because, to me, the powder makers know that red blooded American men will operate under the thinking that a little is good and more is better. That really is not true as each shooter uses a gun in differnet surroundings --different altitude, different atmospheric pressure, different humidity, different temperature, etc. You have to become familiar with you particular gun and your particular comfort level aboutr felt recoil, and respect the limitations of the manufacturing differences in your gun, and most of all your levewl of safe operation procedures--some people take greater risks than others. As if the differences about load data vastly differ among manuals, there's crazys like me who insist on using cast flatpoints in .308. I use a Ranchdog 170 GCFP for my .308 which must be seated deeper than "normal" for proper cycling--resulting in a need to reduce powder charges. Reduced powder charges save me a little money for more shooting. I've been studying Lee's pronoucements about shooting cast bullets according to power levels he calculates based on hardness, and I'm not convinced of his theory for me and my gun (YMMV and you might be convinced). I buy Lyman hardball alloy from Rotometals to use in my .444Marlin, and I'm most confident I shoot that alloy beyond what Lee's calculations call for. I'll admit I've not done his hardness testing, but also feel my 265 grain RanchDog RNFPGC bullets in the .444Marlin are leaving the barrel at 2000+ fps (but not max) with no leading using 50/50 alox/lard as a lube. I feel that my gas checks might resist leading to some extent, and they change to overall prespective about Lee's calculations on lead bullet hardness.

rimrock

[Time Bomb]

I havn't been reloading long and had a similiar problem with my lee information,my collet dies had a 85 grain max of r22 with a 165 grain bullet in 300 weatherby and the new lee loading manual says 83.I cross referenced my lyman 48 manual and it says 85 so who's right.The manual and a lot of people agree starting loads are more accurate and easier on brass but sometimes going to max gives better accuracy.A recent example I am loading speer 400 grain flatpoints over h4198 in my 45/70 in starline brass,as I went from 46 grains to 50,.5 grains under the max groups got tighter and tighter until I am at .5 to .75 at 50 yards with xs sights so sometimes it's nice to know how far you can take for best results.