what do you do when there are ONLY load data for jacketed...and not cast?

[mozeppa]

.380 doesn't seem to have load data for cast ...but do for 100 grain j-words.

same for others ..the weights are same just not the boolit material.

so... what do you do?

how do you fudge the load data?

[aspangler]

Look it up in the Lyman Cast bullet Manual. Its there.

[Hickory]

Keep in mind that lead boolits will pass through the bore with less resistance and less pressure than jacketed bullets.
But that is not a license to up the powder charge hoping for more velocity, on the contrary, reduce the load 15-25% and work up like any other load development procedure.
It is always good to have 2 or 3 sources for loading data.

[Ola]

I've been using the jacketed data from the beginning. Not by choice, but because I have to. Vihtavuori is the powder we have available, and there is a limited data for lead bullets in Vihtavuori manual..

The only problem has been too light starting loads. I'm talking about the minimum charges for hand guns. It's quite rare problem and when it happens I just increase the load until the powder burns completely.

[buckwheatpaul]

Pet Loads by Ken Waters....

[dragon813gt]

Use the starting charge and work from there. I have Quickload so I will use it as well.

[popper]

I've been using the jacketed data from the beginning Me too, no loading book but I do use the online manufacturer's data if available, as a check. I adjust COL for my guns.

[DougGuy]

I always thought that since lead is USUALLY less resistance than j words, I could go up 10% in boolit weight over the same powder charge. In all honesty I think as the alloy gets harder, the more resistance a cast boolit provides in the throats and the bore so maybe this difference between cast and j word is only applicable to a soft cast boolit?

[sigep1764]

Like others have said, start 10% lower. I load 5 of those then go up .2 grains and load 5 more. I do this til I'm 10% lower than max. Then shoot them. Inspect primers and case interiors and check accuracy for each set of five. Pick the best or the one load you're most comfortable with.

[runfiverun]

no it's due to engraving pressure.
your hardest cast boolit is still about half the hardness of a copper wrap.
you see many different [start/end] loads with jacketed bullets because of case capacity and/or engraving pressure of the bullet itself.
use a hornady xtp in the 9mm and try using data from speer or sierra and you just loaded a box of proof loads.
throw a 10gr heavier cast boolit in there and the shape determines case capacity.

you have to look at all the variables and make your load choices based on what you see.

[country gent]

This can be a slight issue in handguns where bullet wieghts coinside and faster more approriate powders are used. Your example of 380 used shows this a 100 grain jacketed and 100 grn cast are almost the same charge so starting light and working up to function and accuracy in the jacketed parameters is good. Its easy enough to look and see what powders for cast are pedomeniant in similar sized cartridges also. In rifles this becomes more of a question due to added capacities. The lyman cast bullet handbooks are good for alot of data, some others also have it. The other thing is to do it like a true new wildcatt cartridge and check water capacity, comparing it to other cartridges with data and the same case capacity. Then starting on the light side and working up slowly and carefully. In the pistol calibers most data will somewhat interchange but it is always wise to start light and work up. Some of the traditional loads for light target loads may not be found in any manuals.

[Stilly]

Pet Loads by Ken Waters....


Oh gawd I wish that they had done a better job with that single volume that they put out.

I am starting to see him as a snobby guy that does not like to shoot fun and odd things with some of those calibers...

[Ola]

you have to look at all the variables and make your load choices based on what you see.

All in all, that is the most important advice given in this thread. But it takes some experience and brainwork to be able do that.

Before one reaches that level of decision making, he/she needs some basic guide lines. Maybe we should try to give them those?

Something like this?

Minimum charges for jacketed can be used if:

a) cast bullet is equal weight or lighter
b) cast bullet is equal length or shorter (well, they usually are if (a) is true)
c) the shape of the bullets is similar
d) C.O.L is equal or longer

Did I miss something?

[gloob]

I always thought that since lead is USUALLY less resistance than j words, I could go up 10% in boolit weight over the same powder charge.
In a revolver, yeah. In a locked breech semiauto handgun, it's exactly the opposite.

It has nothing to do with alloy hardness or friction or lube. Well, not directly. It is simply because cast bullets go FASTER with the same amount of powder, and that makes for more recoil/slide-velocity. Locked breech semiauto handguns are recoil-operated, and they only function within a certain range of recoil.

Blowback pistols are different and don't necessarily go one way or the other. But in general, they will usually have a lower max charge with cast bullets, too.

What I do is to take a starting jacketed load (if not listed, take 5% off the max jacketed data). Then take 10% off of that. Then I will cross reference to any known cast data I have for different powders. Just to make sure the load looks sane.

[Harter66]

I have 2 rifle cartridges that lack data badly . 1 allows for a cousin cartridge that is especially close . The 32 Winchester Special and Remington. They are more like a standard and an AI with a 2%capacity gain. Like and AI 308. :)
The other is the 6.8 SPCII with a bolt gun and 1 particular powder I found the absolute ceiling to be about 10% below the published max however I made some in retrospective some stupid mistakes . For example the ready to load boolit was 11 gr heavy for the data ,8% too heavy, the data was for the SPC at a 1-10 twist where I had a 1-8.5 . The quest was also a neck up from 277 to 284 . This all gave me an even break at 4% under the maximum load data where this cartridge/boolit/powder spiked .

It is hard to imagine a cartridge with a cult being nearly 20 yr old and having data for only 6-7 powders and about 10 bullets . Data that was available is gone and very little new data is coming.

There are cartridges that will exceed jacketed data with cast pressure restrictions in some cases make it happen the 32 Remington will reach the 32 Winchester data for jacketed maximum velocity below the start load with a cast boolit of the same weight and profile. In the 6.8 the new NOE 279-124 fits in the neck with the check above the neck/shoulder point . The 27-130 RCBS to chamber has the same case intrusion as a Hornady 120SST but weighs 137 gr with check and lube. The NOE boolit weighs in at 129 seats to a correct 2.29 oal but has no case intrusion at all I expect to be able to use jacket data all but directly because of the increase in case capacity. Keeping in mind that all the load data is for SPC and the rifle is SPCII which is sort of like using a Weatherby finish reamer in a 7mm Remington without shoulder changes , long leade and low angle to the lands .

Ultimately it will be your combination that decides on the maximum .
With more specific details we could likely point you in a better direction.
I'm waiting on the new 51st edition of the Lyman book as neither the 4th CBH nor the 49th list the 6.8 Remington even with jackets.

[runfiverun]

OLA:
the thing you missed is where to start.
for a semi-auto you absolutely have to start with functioning.
the round has to feed from the magazine 100% of the time every time.
this is going to determine your leftover/useful case capacity.

I have some 9mm rounds that the oal of the cartridge is .980ish [off the top of my head]
from that I have to determine where the bottom of the boolit is sitting in the case and figure my loss in capacity versus a similar weighted bullet.
once I figure that out, I then can make a guess [yes it's a guess] at how much less powder I want to start with.

now is the boolit hitting the throat? another deduction.
how about case capacity to begin with more/less?..... deduction or not again
how about the powder itself?
titegroup is famous for not liking tight spaces.
so this is a place I wouldn't even use it and move along to something like 231.

now moving on to another more traditional less case filling but slightly heavier boolit I still have to ask myself those same questions, but this time I come up with different answers.
I could use the data I already have and work forward again, or even break out that old bottle of titegroup and start using it.
my ballistics are basically the same, my boolit weights are within 5 grs of each other.
but I can now safely use the touchy powder.

[dsh1106]

.380 doesn't seem to have load data for cast ...but do for 100 grain j-words.

same for others ..the weights are same just not the boolit material.

so... what do you do?

how do you fudge the load data?

I found this POST useful ----------> http://www.handloadersbench.com/forum17/32771.html

[Ola]

R5R

I agree, that is the way an experienced loader does it. Combining safe pressures to function (and also accuracy) at the same time is possible with enough knowledge and experience. You can guess because it is an educated guess.

But you can't expect a beginner to do that. If we give guidelines to a beginner we can forget the function. Safety is all that matters.
So I repeat (with one minor change):

Minimum charges for jacketed can be used as a starting point if:

a) cast bullet is equal weight or lighter
b) cast bullet is equal length or shorter (well, they usually are if (a) is true)
c) the shape of the bullets is similar
d) C.O.L is equal or longer

Did I miss something?

[Love Life]

For handguns, if no weight listed for cast then I just use the data for jacketed. Start from the start load and work up.

[runfiverun]

he can unless he makes that critical error I pointed out earlier by using the wrong bullet [like the xtp].

you have to start somewhere.
but being new is not an excuse to go forth blindly, reloading is an education in more ways than one.
be that math skills or following directions [recipes] or following some common sense rules and doing your homework on the components you bought from uncle charlies travelling emporium of reloading stuff.
a person needs to set his/her own guidelines to follow when a change is confronted.

the one and only rule to reloading that applies to every situation is: start low and work up.

[trapper9260]

What I have done for cast to shoot out of my semi auto for 308 win is I use the start load for jacket of the same weight on the mold to the same to the jacket ,but the cast will be higher in weight but what I have done is weight all my boolits after I GC and size and lube and take the high side of the most and go from there with what I first stated to what data to start with.

[Ola]

the one and only rule to reloading that applies to every situation is: start low and work up.
But not too low. The powder companies usually give min and max loads. The people at Vihtavuori told me why. Between min and max is the window where "powder burns predictably". Outside that window the manufacturer has measured something they do not like.

Above max is the danger of over pressure, obviously.

Going lower than the min load is usually not a huge problem in handguns. "Unpredictable burning" means velocity variation and eventually squibs.

In rifles... that is another story.

[Blackwater]

Some good points made above, but I hope every new or budding reloader/caster caught R5R's comment, "being new is not an excuse to go forth blindly, reloading is an education in more ways than one."

There seems to be an alarming trend among too many towards group-think - not buying or reading good manuals, especially the front parts that EXPLAIN what to do and much about why to do it that way, so that real understanding is achieved. Rather, some newbies seem to log on and just ask others what they do, and just go along with info from someone they've never met, and do not know the qualifications they may or may not have for giving such advice. That, on the face of it, doesn't seem like a real good idea, does it?

The internet is a great source for info of all types, and this place is chock full of very highly knowledgeable and experienced reloaders, but there's some occasional bad advice posted here, just like there is everywhere you look on the 'net. It's usually pointed out, though, so this is one place where I'll trust much of what's posted if it's something I have no prior experience with.

However, when we have questions, and don't have data, the simplest and still the best answer is to GET MORE DATA, and the stuff in print is your best guide. After all, they can be sued and put out of business if they post bad data. Faceless posters who aren't even using their real names (and for good reason in this realm where ID's can be stolen, etc.) aren't my first choice for data! The old timers I know here are even taken with a smidge of salt, because I'm shooting MY gun and it may not be quite the same as theirs. Guns DO vary, even among the same make and model and barrel length, so the only real way to know what works in a given gun is to try various loads and see.

The only thing I can add as to using J-data for cast, is that in some calibers, cast MAY produce either more OR less pressure than a J-bullet, and for someone who's not very experienced, the ONLY way to approach it intelligently is to GET MORE DATA, or either start extra low and work up, but in certain circumstances, even that can produce problems, like stuck bullets in barrels, or excessive pressures.

Smokeless powders burn in a certain way and at certain speeds at certain pressures and that way is designed into them by the manufacturers. Using them outside the original design parameters CAN often be done, but may well also produce less desirable traits, like incomplete burn. Many powders in use today can, at the point of maximum pressures, begin spiking pressures very disproportionately when used above the point where they burn best and most consistently.

There's just no way to become an experienced reloader without getting all the data you can get, and reading as much as you can. When you do that, things start to really come together, and you start to be able to guesstimate things with pretty reliable regularity, but it's a long haul to get there, and NOT doing the due diligence is a good way to NEVER getting there, so just read all you can as often as you can, and NOTICE what you find in various sources that tend to jive consistently. You'll have many questions along the way, of course, but that's just part and parcel of the learning curve with any subject, this or any other. But this one's a LOT more FUN, so it really shouldn't be drudgery to do this necessary research. The real key is just simply noticing things, and thinking through to the end any questions you have. Excellent way to learn about anything, really.

Good question, and I hope the guys here have helped all the newbies and budding guys "the way." This really IS the best single source available for info on these subjects, and it's due to all the good, experienced and knowledgeable guys who frequent the site. They share their knowledge and experience with any who'll listen, in an effort to learn more themselves, and to help others like we've all been helped through the years. But never use them as an excuse to not get the books and manuals that we ALL really need. Get 'em as soon as your personal economics allow.

Young shooters are often financially challenged, and there's nobody here who won't chime in with help, but a few really DO seem to take advantage of their generosity as an excuse to NOT do their own due diligence, and that's treading on dangerous ground! Sooner or later, that kind of approach is always going to cause problems, and we all hope they're as minimal in consequence as possible, but one CAN glow up guns, and kill other bystanders or themselves with the wrong loads or loading mistakes.

That ain't no small thing, and if any of us EVER abandon the caution always called for, even among us experienced types, bad things can and DO happen! So newbies and budding loaders MUST approach it not with fear, but with due consideration and good, reliable info, and the best way to get that is from manuals, and from reading them thoroughly from cover to cover. Get 'em when you can, and get 'em all! You'll never regret it if you do. You might regret it if you don't. I wish all decisions in life were this easy!

[runfiverun]

OLA::bigsmyl2:
I'm enjoying the back and forth.
a new reloader should pay attention to the window of opportunity we are providing.
learning to read what is going on is also something that comes with experience.
in a rifle load it is quite easy to mistake some low pressure signs for high pressure , and lowering the load even further could potentially lead to a bigger problem.

I have been watching a couple of newer guy's recently ask why their velocity went down when they added more powder, they had stopped getting flat primers the step before.
man oh man how do you get them to understand they already seen high pressure and are pouring more into the case but are not getting the velocity usually associated with it.

[Ola]

R5R.

Oh now I understand why you are so hesitant. Here reloading is not very common and people who start reloading are usually pretty smart. They read, ask and think before dipping the powder can. I'm used to teaching them.

So we must not make it too easy for the beginners?:-P Yeah, I can understand it. The hard road is the safest road in reloading.

But I'm pretty sure we could make a almost idiot proof checklist for them.. If we really wanted.
That checklist would eventually be REALLY long..