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Kick1121
11-09-2015, 02:51 PM
hello all i need some help here is load data universal for cast and jacketed bullets ? i really cant find data for my cast bullets
so I use data i can find but looking through reloading manuals even if a jacketed bullet weight is the same but by different manufactures the powder charge changes why??? if bullet weight is the same and diameter is the same will it have the same pressure or less due to the cast being softer ? any help would be great thanks:veryconfu

Cowboy_Dan
11-09-2015, 03:05 PM
You have more than just weight and diameter to think about. Also look into how deep each will be seated as this impacts the volume of the powder space. Smaller space yeilds higher pressure, ceterus paribus.

deepwater
11-09-2015, 03:15 PM
Engraving the rifling in a Cu jacketed bullet increases pressure more than in a Pb boolit. All things equal, the Pb boolit will have a higher muzzle velocity than a jacketed one due to less friction in the barrel.


deepwater

Wayne Smith
11-09-2015, 03:17 PM
Engraving the rifling in a Cu jacketed bullet increases pressure more than in a Pb boolit. All things equal, the Pb boolit will have a higher muzzle velocity than a jacketed one due to less friction in the barrel.


deepwater

And will do so with lower pressure, to boot. For this reason jacketed data can generally be used with cast boolits. However, Lyman publishes a Cast Bullet loading manual. Lots of data for cast there.

mdi
11-09-2015, 03:57 PM
No, not universal. No mystery, cast is different from jacketed and jacketed bullets are different even if they are the same weight/diameter. Shape, alloy, seating, and friction values all have an effect on load data. For new reloaders trying lead bullets need to get a dedicated cast lead bullet reloading manual; Lyman's Cast Bullet Handbook is prolly the most popular one. Also, read the "How To" section thoroughly before loading cast bullets...

leadman
11-09-2015, 04:31 PM
The cast boolit is not able to (most of them) withstand the pressure of full jacketed loads. As one loads from the minimum cast loads there will be a point when the boolit alloy will fail. I have shot heat treated linotype boolits that exceeded jacketed velocity. All aspects of the gun and load need to be compatible.
My advice to you is to buy the Richard Lee's second manual as it has very easy to understand information on pressure versus alloy strength. Also info on how to determine loads for cast.
Another manual you should have is either of the 2 manuals from Lyman with, in my opinion the 3rd edition is more informative for a new caster.

Blackwater
11-09-2015, 09:15 PM
Good comments above, and all basically true, but I've noted that with cast, low pressure/low velocity calibers like .38 Special tend to give better velocity and lower pressure than with J-bullets, whereas, sometimes with magnums, it can depend on alloy. Very soft bullets driven to high velocity may well yield more pressure than the Jbullets. It seems that once the J-bullets' sides get engraved, they become fairly easy to push down the barrel, whereas soft lead that is being pushed beyond the pressure level it really wants to work within, seems to get hammered in the rear by all that pressure, and due to inertia, the front and middle sections are just driven outward as well as forward, thus increasing pressures.

If you're in search of a single, always applying principle, I doubt you'll find one that's really very reliable, and the only real answer, universally, tends to seem to be "It depends." Sorry if this isn't what you wanted to hear, but it's what I've observed, and many others have reported. Just about all of reloading seems to indicate that we all really HAVE to think and reason our way through each step and principle involved in the process. Trying to go by hard and fast rules CAN get one into trouble if we believe them too universally.

runfiverun
11-09-2015, 09:27 PM
if your talking about 90% of the handguns out there yes you can pretty much switch one out for the other.
if your talking about rifles you can get away with it in some and actually exceed jacketed velocity's.
the other 95% of them will lead to disappointment for sure and you'll start to learn something about how cast actually works.
bhn of the boolit is on the list, but just making them hard will not get you velocity and accuracy.
proper fitment of a 3% antimony boolit will get you further down the road to 2500 fps than 35 bhn will, and that's where the learning starts kicking in.

I'd just go buy the lyman number 3 and number 4 manuals and read them from the front page up to the load data part and go from there.

bangerjim
11-09-2015, 09:31 PM
You can use a "rubber ruler" to calculate cast vs FMJ loads! :veryconfu That is about how accurate any given rule is. As said above, there are MANY variables that come into play.

And to throw another one at you: Many on here have found that PC'd lead boolits can be loaded at or nearly at FMJ loads. I do it. With no problems. Only hard/fast rule I have personally is: "use a Cu GC when physics dictate and do not think PC is a substitute for a GC".

So, basically follow safety rules and start low and work up your lead loads.

Get the books. I recommend BOTH Lyman 3 & 4. Each has it's own unique value to the cast reloader. Lee's book has a mix of jacketed and cast data which I use on rare occasions. Normally the Lymans have everything I need.

You can get a good inexpensive reprint of #3 at Cornells.com.

bangerjim

Hick
11-09-2015, 09:48 PM
I'm new here-- so If i'm stepping out of line to add to the question in this thread please tell me. I'm looking at a similar situation-- trying out 170 hard cast flat nose with my 32 WS. One of the older Hornady manuals has 170 FN (jacketed) load data from 2100 down to 1700 fps, but the Hunter Supply hard cast is limited to 1600 fps. By my calculations, if I drop down about 5% below the Hornady starting load I will be around 1600 fps. I've checked the loading density and it will be about 75%. Any of you with more experience have any thoughts on this?

bedbugbilly
11-09-2015, 09:59 PM
"Lyman Cast Bullet Handbook" . . . if you are casting and shooting cast . . . you need a copy. There are four editions . . . . I have 2nd and 3rd and refer to them all the time for cast boolit loading data. Doesn't answer your questions but it's important to have good references . . especially when casting.

runfiverun
11-10-2015, 12:29 AM
sometimes you have to extrapolate a little.
unfortunately this is where you can get into trouble, or just plain out have poor results.
if those store bought boolits are plain base your gonna have much better results starting at about 1200 fps and working your way forward, you'll find an accuracy node about 1300 fps or so.
you'll probably find they are doing a little bit of advertising and basing their claim on bhn numbers and not the real world facts of fitment and powder timing to get better results.

I use an older ideal mold in my 32 Winchester [same one I use in my short throated 8 mauser] my alloy is the good old ww cut with soft lead and a small amount of tin is added into the mix.
my base bhn is a stunning sumthin like 10 maybe 11 [shrug]
the trick is the gas check helps and my sizing die is 324, the nose glides into place and IS lightly engraved by the rifling giving me a good straight start.
load details don't much matter after that part, I use bout anything from unique or 2400 up to 4198 and even as slow as 4831.
it just depends on whether I think I need to exceed jacketed velocity's or if I just want about 2,000 fps.
a 185gr boolit at @2300 fps generates some recoil in a model 94, so I don't think I 'need' that too often.

Grump
11-10-2015, 02:36 AM
I believe Blackwater gives the best info here. Read it carefully.

Back when the .40 S&W was new- ish and the Glock kB! was much in discussion, I carefully studied Winchester's published handgun data because it had pressures listed and a fair number of lead bullet loads in there. Know what I found? Max charges for lead bullets were 3-5% lighter than for jacketed more often than they were identical or nearly so, with equivalent pressures. Think there was only 1 or 2 I found where lead charges were heavier than max for J-bullets. The general but NOT UNIVERSAL trend was lead shoots at higher pressures for the same powder charge, and max pressure loads for one bullet go about as fast as max loads for the other type, with lead getting more speed at the same charge weight but with higher pressure.

So I use my chronograph to measure pressures, sorta. If that powder is supposed to top out in pressure-tested loads at x,xxx FPS, then that's where I stop. If the powder with that weight (best if identical bullet) gives me x,xxx PLUS another 75 more FPS, I don't say "Hot diggity!", I say "Uh-OH!!!".

So my recommendation is go ahead and use jacketed starting loads for your lead boolits, but STOP when your velocities are matching top speeds for those jacketed bullets. And don't forget to factor in barrel length!

Lead Fred
11-10-2015, 04:45 AM
I shoot cast 430gr Ranch Dogs though my 45/70 Marlin.
Someone gave me a sack of Remmy 405s.
I used the same charge in both.
The store boughts hit higher on the target
and my arm was just as sore
Sure glad I got a Limb Saver 10003

Tackleberry41
11-10-2015, 10:58 AM
Sometimes you wonder about loading manuals. I have 5 now, Lee generally just reprints what others do. Bought a Hornady recently, its useful, and not so useful. It has more calibers in it, newer ones and less popular ones. But only for bullets they sell, and even then not really. 45 colt they only list for bullets that can be roll crimped. So no listing for the other XTP like 200 or 230gr.

I was skimming thru one I had printed out. 'Western powders' or Ramshot/Accurate arms. They now have a 3rd 45 colt section, standard pressure, ruger only, and 45/410 chambers. Only place I have seen it. Its a bit odd, as the charge levels are higher, min 45/410 load is max for standard pressure. But pressure is actually lower. I presume due to the way the chamber is made, alot of the gas just blows around the bullet until it reaches the rifling.

The Lyman book is very useful, but with less popular calibers you do have to some extrapolating. With jacketed bullets, the 7.62x54r is in between 308 and 30-06 by charge levels. 7.62x54r data is a bit limited at times. So you can usually find a middle ground between 308/30-06 and not have issues. Yet the Lyman data, 7.62x54r uses a higher powder charge than 30-06.

Then you get into difference in test methods. Most would agree H110 is the same as W296. Load data from the company, where they list for both, is exactly the same. Yet you can go find data in other places where its different.

mongoose33
11-10-2015, 11:31 AM
If I'm trying to figure out a load for a bullet/boolit for which I don't have a reloading manual that gives me guidance, I make some educated guesses and then work it up.


I personally cannot reload without a chronograph. It is not a replacement for a direct measurement of pressure, but much like Grump discusses above, I use it to see if I'm getting results that make sense.

In other words, I start low with a couple rounds and see what kind of velocity I get. If it's out of range of what I'd expect, I back away and rethink it. What's in the books is data based on THEIR platform which may or may not be the same as yours--the barrel length might be different, your bore might be tighter or looser than theirs, the boolit alloy might be different, etc.

If my first test rounds, which are low powder charges usually at or very near the start load in the manuals, produce velocities that make sense based on the manuals, barrel length, past history w/ either the gun or the boolit, then I ladder up, increasing the charge incrementally as everyone does.

Of course, I've made these up ahead of time; if something wacky occurs, I may end up disassembling some of the rounds as too hot or too...whatever. But that's why I work up, and a lot of people here do the same thing.

It may not be just a linear increase in velocity; every .2-grain increase in powder charge might, at lower loads, produce a fairly consistent increase in velocity, UNTIL you get close to max or filling the case or whatever. You cannot extrapolate, which is one big reason why I want to shoot these over a chronograph. If I see a spike in velocity beyond what I expected, I'm done--and the only way to reliably determine that is over a chrono.

Everything else is guessing, IMO and, as usual, YMMV. Chronos aren't that expensive--put one on your Christmas list if you don't have one.

bangerjim
11-10-2015, 11:51 AM
Remember for those new folks ( and those of us that tend to forget due to olde-tymer's disease!):

There are TWO (2) LYMAN books on the shelves out there.

One is for some cast and some jacketed ( rarely used by me as I do not load FMJ's) Limited cast data.

One is for CAST LEAD only........my bible for load data. 100% cast data.

I would say for casters....buy the Lyman Cast Bullet Handbook #4. And get a reprint of #3 from Cornell's. Both have excellent cast load data & technical info.

Cronos are great for those that shoot outdoors. No good for those of us that regularly shoot indoors. My indoor ranges do not allow them because you have to go out in the lane to set it up! And florescent lights do not agree with some. Too bad someone does not make a good reliable and cost-effective strap-on one that works for rifles AND handguns for cast! So far, I have not found one. Anybody know of one that actually works?

If you have one and can use it and it works for your needs.......more power to 'ya!

banger

quilbilly
11-10-2015, 12:02 PM
Engraving the rifling in a Cu jacketed bullet increases pressure more than in a Pb boolit. All things equal, the Pb boolit will have a higher muzzle velocity than a jacketed one due to less friction in the barrel.


deepwater Lubed lead boolits also are more slippery than jacketed as they travel down the bore. It varies from caliber to caliber but my chronograph has shown that my cast boolits can have an MV of as much as 150 fps faster than jacketed of the same weight and same powder charge. For me this has been particularly true of rifle calibers so it allows me to be more economical with powder.

runfiverun
11-10-2015, 12:06 PM
I think the new magneto speeds do just that.
they look like a bayonet sticking out in front of the gun.
they will give you an actual muzzle velocity also.

fredj338
11-10-2015, 05:24 PM
Engraving the rifling in a Cu jacketed bullet increases pressure more than in a Pb boolit. All things equal, the Pb boolit will have a higher muzzle velocity than a jacketed one due to less friction in the barrel.


deepwater
I have never bought into this theory. Less friction, less pressure, less vel. If you have ever loaded moly coated bullets, same design & weight, they need a little extra powder to get vel up because of less friction. Friction = pressures, all things being equal, higher pressure usually equal higher vel.
My theory, lead bullets are slightly larger & seal the bore better, allowing for higher vel with less powder because pressures are up. The malleability of lead offsets the slight increase in friction between lead & steel. Just a theory though but the less friction=higher vel, just doesn't show up over a chrono. Evenif you coat the lead bullet, the HT or PC is slipperier than bare lead but you would be hard pressed to find much diff in vel.

bangerjim
11-10-2015, 05:35 PM
I think the new magneto speeds do just that.
they look like a bayonet sticking out in front of the gun.
they will give you an actual muzzle velocity also.


I have looked at those, but reviews are mixed and all indications are they only work on long guns. And set-up can be rather tricky. There are adaptors you need to fit up and handgun are just not there. The technology should work on wheel guns, but I am not just ready yet to plop down $350+ for one to play with.

It sure would be nice to have a measurement device that works indoors and outdoors, does not have to be mounted out front of your shooting station, that does not look like an invading alien ship, and is just a simple strap-on "thingy" with a wire to a box that tells you projectile speed.

Mabe in the next life?

Grump
11-10-2015, 09:05 PM
I have looked at those, but reviews are mixed and all indications are they only work on long guns. And set-up can be rather tricky. There are adaptors you need to fit up and handgun are just not there. The technology should work on wheel guns, but I am not just ready yet to plop down $350+ for one to play with.

It sure would be nice to have a measurement device that works indoors and outdoors, does not have to be mounted out front of your shooting station, that does not look like an invading alien ship, and is just a simple strap-on "thingy" with a wire to a box that tells you projectile speed.

Mabe in the next life?

Hmmm...how about a bullet trap that measures the kinetic energy? Like that thing that Drago or whoever the Soviet was punching in that Rocky movie??? I'm sure that the amount of energy diverted to heat can be allowed for (If it even amounts to more than 1 ft-lb for us saddled with non-metric...), and an appropriate trap medium will also prevent any significant energy being diverted to mashing up the bullet.

From KE, bullet weight is all that is needed to calculate velocity.

The device could be put on a rolling tripod and shoved out into the firing lane of an indoor range, too.

Or you could go lo-tech and make a ballistic pendulum, with something like a throttle position sensor to measure the "swing"...

I just wouldn't want to manually run the math to calculate the energy then calculate velocity. Software. SOFTWARE!!!

mdi
11-11-2015, 01:13 PM
Hmmm, lots of theory tossed around...

If I were to talk to a new cast bullet caster/reloader/shooter I'd suggest the following; Get a Lyman Cast Bullet Handbook, 3rd Edition if possible (IMO a better starting caster's reference than the 4th). Read it thoroughly, mebbe a couple (3) times. Look up a load you would like to try in your gun. Slug the firearms you are going to shoot lead in, and if necessary, find a sizing technique that suits you. Then buy molds, tools, lube, and components. Load to book data starting at the "starting loads". After casting, loading, shooting a bunch of "book loads" then try extrapolating load data...

K.I.S.S.; you gotta learn to walk before you run...:D