whats the cast boolit "rule of thumb" on loads?

[mozeppa]

if all you have to load is cast bullets and no copper jacketed ones.

AND...there are NO loads listed for your boolit or its weight.

i have 100 grain cone nose cast...and all i'm able to find loads for are jacketed at 90 grains...or 110 grains.

for the 100 grain cast, which load recipe do i use ? ............the 90 jacketed or the 110 jacketed recipe?

in other words ... do i go to the nearest lighter jacketed for load info...or the nearest heavier jacketed
for load info?

am i making any sense here in what i'm asking?

[Harter66]

Makes perfect sense to this ol'wrench grinder .

The guide is to start at the start load of the next heavier bullet .

Until I get a feel for/depending on the gun , boolit and cartridge I may even treat the start load of the next lighter bullet as a max load . Depending on the jacket data and range of the load data .

[Harter66]

As an example I know of a 120 gr boolit load that has a load window of 14-26 gr of Unique . In that particular platform and cartridge I'm good to go with a 14.0 start on 125 gr boolit in a 264 WM in an FN 98 . The 140 gr data is 12-22 gr I think . The 26 sticks as it is what we loaded in 1 1/8 oz 12 ga .

Don't use this with checking it out .

[JonB_in_Glencoe]

you need to be careful when extrapolating Data. There are too many "exceptions" to have a valid rule of thumb, and can quickly get into trouble. If you are unsure enough, that you feel the need to ask a vague question(as you did), I'd think it's prudent for you to ask a specific question, with specific details including caliber, powder, and source of data...ect...

[EDG]

You can extrapolate data fairly easily if you have a large amount to extrapolate from.
1. You probably need 5 to 7 reliable manuals with data for your cartridge.
2. Visually inspect the data for uniformity. Make sure it makes enough sense to pass a sanity test.
That is heavier bullets have a lighter charge or powder and the differences between bullet weights are the same among the manuals.
Then throw out any outlier data. Any data that is significantly higher or lower than the rest should be discarded.
3. Take the rest of the data and average it. Average the heavier bullet data and the lighter bullet data. Then you make an educated choice based in the averaged data.

you need to be careful when extrapolating Data. There are too many "exceptions" to have a valid rule of thumb, and can quickly get into trouble. If you are unsure enough, that you feel the need to ask a vague question(as you did), I'd think it's prudent for you to ask a specific question, with specific details including caliber, powder, and source of data...ect...

[RogerDat]

I was told that for cast lead bullets if forced to use jacketed load data then start with 60% of the jacketed max. Would be enough to not squib and lodge in the barrel and well under max for lead. Got this when I called a powder company looking into powder equivalents and load data for a heavy .303 British. Was using the ADI tables for data and then the ADI equivalents table get US brand that was same as ADI manufactured for Australian consumption under their own brand name.

Multiply max grains of jacketed by .6 to get 60% (easy way to plug into calculator).

Best is to keep looking because there is a good chance someplace the load data exists. Everything I have read indicates too little powder can make for poor burn & low power due to insufficient pressure. Just as pressure can spike rapidly past a certain point in a powder weight, so too it can drop off a cliff below a certain point. Bullet stuck in bore is an alternative way to blow up a firearm.

[JonB_in_Glencoe]

DO NOT reduce H110 or Win 296 by 60%

again, I will state, there are too many "exceptions" to have a valid rule of thumb.

[dragon813gt]

DO NOT reduce H110 or Win 296 by 60%

again, I will state, there are too many "exceptions" to have a valid rule of thumb.

You can add a bunch of other powders that shouldn't be reduced that much. In the case of W296/H110 the last info they published said not to reduce by more than 3% if only a max load is given. Published starting loads are safe and you should not go below them. Unfortunately Hodgdon took this info off their site when they switched to the current reloading data center interface. You'd think they'd have these warnings front and center like they used to.

In life in general rules of thumb are an easy way to screw things up quickly.

[mdi]

Just a couple thoughts; First, keep looking, there is load data for just about every cast bullet somewhere, just find it. And another hint, find a load in your loading manual before you acquire components. Extrapolating load data isn't for the faint of heart or the foolish...

[Harter66]

There are a pretty finite list of candidates for a 100 gr TC with 90 and 110 gr data available . The 110 let's out 380 ,but leaves it wide open for 9mm and a host of 32s and 30 Carbine . It's not even really a question in a rifle .
His other active thread is about miss measured AA5 in a 9mm with no data sources to cross check .

If we are up to cast bullets and using them in alt cartridges there a pretty good chance that we wouldn't be using a half case of H110 with a standard primer .

Does every bit of generic information have to be disassembled until it looks like the I before E except for ...... nevermind there's as many exceptions as there are applications for the rule .

[Der Gebirgsjager]

True, all true. But, in the example given by the OP, I think that it's certainly safe to "split the difference" on the powder charge when you have two published loads and one is for a bullet 10 grains under and the other is for 10 grains over using the same powder.

[DougGuy]

Not so fast.. First and very important, look at the heavier boolit, see if you can determine how far down in the case the base of the boolit is seated when the round is assembled to the published COA. Then, measure your boolit, determine if the base of the boolit is in a similar place, THEN you can begin to extrapolate data from the heavier boolit to your lighter boolit.

You want to avoid a situation where the load you intend to arrive at, has the base of the boolit seated deeper than the published load since this would reduce case volume below the boolit and when this happens all bets are off as far as "generalizing" a powder charge from a different load.

[dragon813gt]

Not so fast.. First and very important, look at the heavier boolit, see if you can determine how far down in the case the base of the boolit is seated when the round is assembled to the published COA. Then, measure your boolit, determine if the base of the boolit is in a similar place, THEN you can begin to extrapolate data from the heavier boolit to your lighter boolit.

You want to avoid a situation where the load you intend to arrive at, has the base of the boolit seated deeper than the published load since this would reduce case volume below the boolit and when this happens all bets are off as far as "generalizing" a powder charge from a different load.

This is why QL is very helpful. It will tell you exactly how much case capacity you have. Like an computer program it's GIGO. But when you feed it the right information it makes working up loads a safe experience.

[W.R.Buchanan]

OK guys Exactly what caliber are we talking about?

Is this a 6MM rifle or a 9MM pistol cartridge? or a .380 or 9x18.

Kind of makes a big difference.

H110 is not a suitable powder for any of those.

It is hard to believe that there isn't any data readily available for what you are trying to do, Whatever that is?

Goto www.loaddata.com or get a Cast Boolit Loading Manual like the Lyman one.

There will be data for every weight boolit for your particular cartridge there is.

Randy

[jonp]

Not so fast.. First and very important, look at the heavier boolit, see if you can determine how far down in the case the base of the boolit is seated when the round is assembled to the published COA. Then, measure your boolit, determine if the base of the boolit is in a similar place, THEN you can begin to extrapolate data from the heavier boolit to your lighter boolit.

You want to avoid a situation where the load you intend to arrive at, has the base of the boolit seated deeper than the published load since this would reduce case volume below the boolit and when this happens all bets are off as far as "generalizing" a powder charge from a different load.

^^ I was just going to type something similar but DougGuy beat me to it. When approaching a bullet that has no data I choose a similar profile then the lowest amount of charge of the next higher bullet weight, reduce 10% and start off paying close attention to my chrono for odd spikes or readings.

[gwpercle]

With just a little more information I would be glad to look up some cast boolit data for you, I have several manuals.
Why some think a lack of information will help get correct answers I will never understand.
Gary

[Oklahoma Rebel]

one said " keep looking, there is data for everything out there" I have looked and looked and looked, for 9.3X62 285gr cast, cant find any data for any powder ( would like to use imr4895 or varget), what now? min charge for 285 jacketed X .90??? thanks-Travis

[Rcmaveric]

I would have looked for a cast bullet of equal weight with cartridge of equal case capacity. You start dropping jacketed loads with slow powders and your gonna start a fierce debate about sudden ignition. Lee's modern Reloader manual 2016 edition gives an amazing section about how to reduce loads. I am not gonna quote what it says because I loaned that manual to a friend and never got it back. I need to buy it again. Only 16 bucks and well worth the information.

Sent from my SM-G925T using Tapatalk

[rking22]

If your looking at 380 9mm type situation I'm more concerned about the case capacity difference than 10 gr of bullet wt. In 243win the different weight isn't an issue at the load levels for good cast performance and neither is the case capacity. Now, 1/10 inch deeper in a 9mm case can turn a start load into a max load right quick! I agree, keep researching , there's most likely some pressure tested data for your bullet somewhere, else quickload for a sanity check.

[mozeppa]

ALLOW ME TO CLARIFY.

100 grain cone nose for a .380 sig sauer......you pick any powder you want i have most all varieties in the pistol range.