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Load work up question

2K views 18 replies 5 participants last post by  Mr_Flintstone 
#1 ·
I'm still in the beginning stages of reloading, and I made a mistake at the store. I was at a local gun store buying some bullets, and I picked up a box from the row that had 150 gr LFP. When I got home and opened the box, I realized that I'd actually picked up 158 gr JSP.

While this won't cause a problem loading 38 spl, my intention was to load some 38 LC. There doesn't seem to be any data for jacketed bullets in 38 LC, and the data I I'd have is for lead. As I don't want to go buy another box of bullets, I started reading my Lee manual. It gives the load work up formulas as:

10% change in bullet weight causes -4% change in velocity, and 8% change in pressure.
10% change in charge weight causes 8% change in velocity and 20% change in pressure.
10% change in case volume causes -3% change in velocity and -13% change in pressure.

I started with a low 38 spl load using 158 gr FTX and 3.5 gr Titegroup @704 fps and 12400 CUP. Hornady says I can use JHP interchangeably with JSP or FMJ with the same weight.

Using the formulas, if I change the case volume -15.2% from 23.7 gr to 20.1 gr, I get 14848 CUP and 736 fps. To get back to the original pressure, I change the pressure by -16.5% resulting in a charge weight of 3.2 gr @ 686 fps at 12400 CUP.

Recalculating for the max charge, I started with 3.9 gr Titegroup @ 798 fps and 15900 CUP, and got a new max charge of 3.6 gr Titegroup @ 779 fps and 15900 CUP.

I don't have software to check these values, so I'd like some opinions from you guys. Do these seem like reasonable values? I'll be shooting them in a modern 38 Special that is +P rated.
 
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#2 ·
For a new reloader extrapolating load data from different bullet loads can get dangerous. Powder charges aren't linear in pressures and will react differently under different circumstances. How much is a box of the proper bullets vs. the cost of a new gun? Or mebbe some finger damage? Maybe an extreme example, but who knows? I'd put the box of 158 JSP on the shelf and buy the proper bullets...

(I have been reloading for over 30 years off and on. I reload jacketed, cast, solid copper, PCed and plated bullets in 10 different cartridges and I won't try to figger load data from a different bullet/powder combination. I haven't had a squib since 1970 and never a KABOOM).
 
#3 ·
I have to agree with mik. The Lee formula's sound good and make sense in theory but not all powders will act accordingly. Just as you can't accurately average percentages, "powder charges aren't linear in pressures" to quote mik.

While I do believe and have proven to my satisfaction that powder charges can safely be extrapolated that has come after over 55 years of handloading for well over 100 different cartridges both common and nearly unknown. It is something I never do on a percentile basis. That's asking for trouble I fear.
 
#4 ·
Thanks guys. Like I said, I'm new at this. I figured since it was in the manual it was good. I never loaded any of these. They may have worked... May have blown up. I called Hodgdon, but they couldn't provide any help. I'll probably just use these for 38 special and .357 mag. I have load data for those.

On a side note, does anyone have experience with the Trail Boss reduced loads formula? It says that you can measure to the seating depth of your bullet, mark the case, fill with powder and measure. Take 70% of this value and use as a starting load for any pistol/rifle straight walled brass/bullet combo. Although it doesn't specifically say so, I suspect this is for lead or cast bullets as well.
 
#5 ·
You are starting off - so take it easy, grow some more whiskers and go by the book absolutely. Don't go trying the 'rocket science approach', unless you are tired of your body as it is.

I am curious about your question about Trailboss in a .38 Special. I guess I don't understand what leads you to this powder. A couple of terrific powders for the .38 Special are Unique and Bullseye. They have been proven for a great many decades. If the powder and charge isn't listed in your published reloading manual - don't use it.

Don't be 'figuring and guessing' - start with the load listed as a "Suggested Staring Grains" and work your loads up until you find the load you and your weapon like. Go slowly and carefully and NEVER exceed the "Maximum Grains" listed.
 
#7 ·
I use some Trail Boss and trust the information on Hodgon's web site. They either developed it or had it developed for a specific purpose so if they can't be trusted, who can? I'm 95% a cast bullet shooter and I use their data for cast bullets. Used as described and instructed on their site I've had no problems.

Soundguy uses more Trail Boss than anyone I know so perhaps he can offer his experience.

I'm like Jim in that I'm curious why Trail Boss in the 38 Spl.? Classic, tried and true loads with Bullseye or Unique are pretty mild of report, generally accurate and light of recoil. 'Course if a fella is just curious and wants to try them all I can say is I've been guilty as charged more times than not.....:D
You can rest easy guys. I'm not going to go all willy-nilly loading stuff up. Right now I have all the reloading data I need, and I don't foresee needing any custom loads any time soon. I've always lived by the motto "if you don't know about it, ask about it." It doesn't mean I'm going to go do it.

Since you're curious, I've been using the Trail Boss (published loads) for really light target loads. I have some really bad tendinitis in my right arm and hand right now, and it's just easier to handle the 38 spl popcorn loads until everything heals up. I just happened to notice the reduced loads guide the other day, and thought that using 70-90% available case capacity seemed a little high; at least a lot higher than published Trail Boss loads.
 
#6 ·
I use some Trail Boss and trust the information on Hodgon's web site. They either developed it or had it developed for a specific purpose so if they can't be trusted, who can? I'm 95% a cast bullet shooter and I use their data for cast bullets. Used as described and instructed on their site I've had no problems.

Soundguy uses more Trail Boss than anyone I know so perhaps he can offer his experience.

I'm like Jim in that I'm curious why Trail Boss in the 38 Spl.? Classic, tried and true loads with Bullseye or Unique are pretty mild of report, generally accurate and light of recoil. 'Course if a fella is just curious and wants to try them all I can say is I've been guilty as charged more times than not.....:D
 
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#8 ·
I planned on resting easy...:D Given the arthritis in my thumbs I understand completely.

Trail Boss is a fast burning powder manufactured to be very bulky, take up a lot of space. As I understand it the powder was largely aimed at the Cowboy Action crowd and designed to do that very thing, take up a lot of space to circumvent the possibility of a double charge. It certainly does that and in turn develops lower velocities. I kinda like the stuff and use it for reduced loads in big ol' cartridges. Reduced in regard to velocity and recoil because it certainly isn't a reduced volume powder charge. It's also one of those powders that doesn't play by the Lee formulae.
 
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#9 ·
The .38 Special sounds like a good choice for you. Sometimes you need to adjust your shooting to your body's needs. I gave up shooting a lot of the bigger stuff when Ole Doc opened me up and put me back together like a Leggo Set.

I've never been a huge fan of super-dooper rifle or pistol loads anyway - but having said that, I did have a .458 Winchester Magnum (that killed at one end and maimed at the other). I do still occasionally shoot my .45/70 Carbine, the ARs and M1A, but my pistol loads are either target grade 9mms, or cast loads with the .45 Colt and .44 Magnum - and both of those are mid-range.

Have you thought about trying .38 wad cutters for your target shooting? Last time I saw those lead bullets in bulk, they were pretty danged cheap. You can work up some very nice, accurate ammo with those, and shoot about as inexpensively as it gets. They are also very mild in recoil.
 
#12 ·
I don't mean to take a crack at Mr. Flintstone but, doe's it sound ridiculous to use the types of formulae he's quoted from Lee to load?

There are enough good load data manuals, powder manufacturers' data, and reliable magazine published (ex. Hand Loader) to provide proper work up loads........why bother to take the risks associated with extrapolation??

I'm honestly surprised to know that Lee would print such stuff.
 
#13 ·
I don't mean to take a crack at Mr. Flintstone but, doe's it sound ridiculous to use the types of formulae he's quoted from Lee to load?

There are enough good load data manuals, powder manufacturers' data, and reliable magazine published (ex. Hand Loader) to provide proper work up loads........why bother to take the risks associated with extrapolation??

I'm honestly surprised to know that Lee would print such stuff.
If you're aware of, and could tell me where to find a good source of reliable load data for 38 Long Colt, I would be most appreciative. So far the only load data I can find is for 150 grain lead and 125 grain lead. I have searched through every manual at the local gun stores, and they just don't publish much for that particular round. I did find an old Sharpe manual from 1937 that had a few, but most of those powders are no longer made, and I have no idea what Bond-A and Bond-B bullets are.
 
#15 · (Edited)
The Trail Boss formula from Hodgon works fine. As I said previously they developed it so I have no doubt it's safe. Evidently you mis-interpreted it. It's 70% of the weight according to the volume. Seems obvious to me you fill the case with Trail Boss to that level, the base of the bullet, weigh it then use the 70% factor. You WILL NOT get 12 grs. of Trail Boss in a 38 Spl. case. I use 22 grs. in my 450/400 NE case and it's about an 80% load. You can probably put 6, 38 Spl. cases in the 450/400 case. Trail Boss is hugely bulky.

There is also formula's for other powders that work just as well. The one developed for IMR-4198 in old Black Powder Express cases is one that comes to mind and it's been proven so often it no longer bears mention. Accurate 5744 also has a safe formula for load calculation. However, to apply any formula to every powder for any cartridge case is pure folly.

Loading manuals are great. So great that I believe it mandatory a handloader have several. Howsomever, there is an unending list of cartridges out there for which no data has ever been developed, ever, period. Among a lot of others I enjoy making, loading for and shooting those old cartridges and if a fella is going to do that he better learn how to extrapolate loads and learn to do it correctly and safely. It has been done safely for over 100 years and can still be done safely but you better have the knowledge and experience to do it. How do folks believe such great cartridges such as the 22-250, 25-06, 35 Whelen, 219 Zipper, 219 Donaldson Wasp, some of the now popular 6.5's and a host of others came about? Somebody had to start somewhere and it wasn't an ammo factory. Experienced and knowledgeable handloaders did the ground work. It is not something beginners should undertake. Nor should someone who has just loaded for common cartridges with a recipe taken from a manual, pulled a lever and never progressed beyond that level. Burning rates of various powders and how they react to pressure, interior ballistics, how bullet weight and twist effect combustion and pressure, strengths and weaknesses of various rifle and handgun actions, when they were made and for what purpose, the effect and relationship that chamber, throat, bore and groove dimensions have with and on combustion and pressure and a heck of a lot more little factors need to be known and well understood before that first load is extrapolated from known data for an unknown cartridge. Until a person can explain all that, understandably, to a 10 year old, LEAVE IT ALONE!
 
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#16 ·
I appreciate the intent first part of your reply. I made an oversight on the measure. From measurements and calculations I made last night, The load range for 38 special with the 125 grain bullets I have using Trail Boss would be 3.1 to 5.0 which is just about the same as the published loads.

As to the rest of your reply, there's no need to get preachy or talk in a demeaning manner. I'll assume it was unintended. I have worked as an engineer, chemist, and more recently as a mathematics and physics teacher. I am well aware of the risks involved in reloading; hence my questions. I know from past experiences that you only build something if you're sure it is stable; you only mix chemicals together that you are reasonably sure won't kill you. There is a learning curve involved in tackling any new endeavor, and as I am undertaking this one alone with only published manuals and internet forums for support, I read what I can and ask questions about what is unclear. You "learn" before you "do". The problem I am encountering is that In my previous work, there are set guidelines, rules, and protocols in place that are widely and easily accessible. Reloading manuals are diverse, and sometimes give conflicting information about procedures and load values; some based in fact, and others in conjecture. As far as internet forums go, it has been my experience that it is like infiltrating a cult where everyone is tight lipped and don't want to give up any information voluntarily. It seems divided into "us" and "them"; like there is a perception that people should already know everything, or they are too stupid to do anything other than follow recipes, and sometimes not even that.
 
#17 ·
I haven't looked at Hodgon's formula on their web site for a while but I want to remember it might not be completely clear as to their meaning. Easy enough mistake to make, for anyone, including yours truly.

Mr. Flintstone, the second part of my post was not directed at anyone in particular and certainly not you specifically. Nor was it intended to be preachy or demeaning but, certainly emphatic. It was based on my experience and that of thousands of others that extrapolating a load can be done and done safely, with complete confidence. Something many preach totally and completely against evidently being either ignorant of how to do so or unwilling to learn. It isn't something to be entered into lightly or without much experience, knowledge and study of the cartridge/rifle combination in question. It certainly isn't for the less than attentive or reckless. Given your credentials and background no doubt you will grasp the details quickly and comprehensively.

To take a cartridge that hasn't seen the light of day in over a century, form the brass, work up a load and put the old piece back to its intended use serves up a satisfaction I don't get from any other kind of handloading or shooting. When I started handloading all those decades ago I didn't expect to end up doing that kind of thing but it sure is fun and what an education.
 
#18 ·
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Mr_ Flintstone, you opened your original post "I'm still in the beginning stages of reloading."

You didn't divulge anything about your age or background.

I think responses you took as "preachy" are from long time, experienced hand loaders stressing "abundance of caution" about doing something that can be dangerous.

I hope you won't be too offended to stick around long enough to learn this forum is different from other forums devoted to shooting. To the contrary, anyone here is willing to freely share their knowledge and experience with anyone else. Seldom will you see a post here by a person who doesn't know from experience what he/she is talking about and willing to go to great lengths to answer questions.
 
#19 ·
I'm not offended, and I fully intend to stick around. After thinking about it, I realize that you don't know me, and you are only interested the safety of those just beginning.

I started with the .38 caliber line because it is so versatile, and after I become more acquainted with everything, I fully intend to pick your collective brains about other calibers.
 
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