Lead vs Jacketed Bullets

[JC676]

There seems to be a fairly large difference is published loads of lead bullet data vs jacketed bullet data when both bullets are the same weight. For example, using a 158 gr LSWC (.357 Magnum), my Speer manual (#14) lists 6.0 grs of Unique as the maximum load but for a 158 gr jacketed bullet, the same manual lists 7.7 grs as the max load.

I understand that driving lead bullets much over 1,100 fps can lead the barrel. But if the lead bullet is of a sufficient BHN (say 17-19 in .357 Mag) I wouldn't think leading would be much of a problem. So is there any other reason one shouldn't, using a very hard cast bullet, load it with jacketed bullet data? As you've probably guessed, I'm trying to get more muzzle velocity without having to pay the much higher price of jacketed bullets, but want to do so safely.

I'm just getting back into reloading after a 20 year absence and I'm now loading several calibers instead of just the .45 ACP. I never had to do much experimenting with the .45 because 5.4 grs of W231 was not only accurate, but according to the chronograph, gave a muzzle velocity that duplicated the muzzle velocity of my carry load.

With retirement on the horizon, I plan to spend a lot of time loading and shooting but I want to do things the correct (and safe) way.

Thank you in advance for any and all replies.

Regards,
Jon

 

[45Colt_Man]

A lead bullet is easier to drive down the barrel than a jacketed bullet. Does not require as much powder to achieve the same velocity. Yes BHN can and does affect the leading. Hope this helps as there are lots of variables.

Dana

 

[Jimbo357mag]

A lead bullet is easier to drive down the barrel than a jacketed bullet. Does not require as much powder to achieve the same velocity. Yes BHN can and does affect the leading. Hope this helps as there are lots of variables.

Dana

If that were the only factor then it would take more powder to reach MAX PRESSURE with the lead bullet. I believe as you get to very high pressures and velocities the lead bullets deform, melts a little along the sides, and has more drag than a jacketed bullets. Gas checked bullets are more like jacketed bullets. And of course the harder lead bullets work better at high pressure and velocity.

If you look at lower pressure and velocity data you will see in general that lead and jacketed bullets require about the same powder charge to get the same pressure and velocity. As you get into higher pressures and velocities the lead bullets have more drag in the barrel.

Just my opinion. What do I know? I'm kind of a novice compared to some on this forum.

...Jimbo

 

[sixshot]

That lead SWC is most likely a swaged bullet (quite soft) & can lead your barrel if you lean on it too hard. If you want to drive a cast bullet at high speed then you want a harder bullet, something that won't "skid" in your barrel & leave it full of lead.
Shooting hard cast bullets at high speed is very easy to do & as you mentioned its much cheaper, also its much easier on the gun. Pretty hard to wear out a barrel shooting proper cast bullets.
The rule for cast bullets is, don't shoot a soft bullet fast & don't shoot a hard bullet slow, so if you have good bullet fit in the throats & a bullet of correct hardness for the velocity you want, well, you are going to be a happy shooter.
The question that comes up is.....what is considered a hard bullet, there's really no stock answer. Lyman uses their #2 formula & it is usually about a 15 hardness, plenty hard for most applications, if you really want to push them fast then either make your own from water dropped wheel weights, Linotype or something equal or you can buy them from one of the many custom casters out there.
Perhaps the finest custom cast bullets are from Cast Performance, you get what you pay for! Also Rim Rock bullets & Mt Baldy are 2 very good ones but there are several if you do a search. Buy them from some of the bigger sporting goods stores & you won't have to pay the freight.
Good luck! If you need some to start, give me an addy & I'll give you some.

Dick

 

[TRanger]

My own Speer manual shows data for the soft swaged lead bullets only. The loads are quite mild. A cast bullet of sufficient hardness can be used with heavier loads, generally with less pressure.

 

[JC676]

Gentlemen,

Thanks for the replies! I have good, hardcast lead bullets that have a BHN between 17-19. It seems to me they should be able to safely withstand powder charges that are listed for jacketed bullets, but I'm certainly no expert which is why I made my original post.

I carry Buffalo Bores Heavy .38 Special +P load which drives a 158 gr bullet close to 1140 fps from a 3" SP101 barrel as my self defense load. Since I can't find any data that comes close to that in the .38 Special +P section of my Speer manual, I thought I'd try to "load down" to that muzzle velocity using the .357 data (in .357 cases) so I can train with something almost identical to my carry load. When I still couldn't find data in a reputable manual that would accomplish that with a lead bullet I got to wondering why. The other problem I've run into with this project is that right now I'm limited to Unique and AA#5. If data from 158 gr jacketed bullets is used, I can come close to my desired result with Unique and I can hit it dead on with AA#5.

Anyway, thanks for listening.

Regards,
Jon

 

[Jimbo357mag]

Gentlemen,

Thanks for the replies! I have good, hardcast lead bullets that have a BHN between 17-19. It seems to me they should be able to safely withstand powder charges that are listed for jacketed bullets, but I'm certainly no expert which is why I made my original post.

I carry Buffalo Bores Heavy .38 Special +P load which drives a 158 gr bullet close to 1140 fps from a 3" SP101 barrel as my self defense load. Since I can't find any data that comes close to that in the .38 Special +P section of my Speer manual, I thought I'd try to "load down" to that muzzle velocity using the .357 data (in .357 cases) so I can train with something almost identical to my carry load. When I still couldn't find data in a reputable manual that would accomplish that with a lead bullet I got to wondering why. The other problem I've run into with this project is that right now I'm limited to Unique and AA#5. If data from 158 gr jacketed bullets is used, I can come close to my desired result with Unique and I can hit it dead on with AA#5.

Anyway, thanks for listening.

Regards,
Jon

Downloading the 357Mags to that level should be no problem with those two powders. If your lead bullets are hard (which they are) you just have to find the right charge weight.

BTY hard cast bullet data is usually a little less than jacketed data. Softer lead bullet data is a lot less than jacketed data. But every case is different. The following start loads are close to what you were looking for I think.

From my Lee book:

158gr lead --- Accurate #5 --- 8.1gr ---1192fps --- 9.0gr Max --- 1354fps --- 39,100CUP

158gr lead --- Unique -------- 6.2gr --- 1188fps --- 6.8gr Max --- 1295fps --- 33,900PSI

I hope this helps,
...Jimbo

 

[Rick Courtright]

I have good, hardcast lead bullets that have a BHN between 17-19. It seems to me they should be able to safely withstand powder charges that are listed for jacketed bullets, but I'm certainly no expert which is why I made my original post.

Hi,

Since you've got a choice of .357s or .38s, downloading .357s sounds more sensible than uploading .38s to me...

Several reasons come to mind, but one of the foremost is safety: IF you choose to load hotter .38s, be they industry standard +Ps , or something trying to duplicate the Buffalo Bores, which may be even hotter (I dunno, but BB has been know to warm up some of their offerings), you want to make sure you have everything well labeled and nobody's ever gonna stick some hotter stuff in a standard .38 than it should be fed.

But there are other issues, including the leading, and pressures w/ lead vs jacketed bullets. What I was taught about using lower powder charges w/ lead had to do w/ obturation, the expansive sealing of the bullet into the grooves of the barrel. Supposedly lead does a better job than jacketed, so pressures CAN go up rather rapidly in some cases. It's always best to stick w/ the books' recommendations cuz there are times when recipes act pretty much in a linear fashion, but others where "just a little more" creates spikes. W/o proper testing equipment, we don't know which is what, despite innumerable Internet posts about "there weren't any pressure signs."

So you kinda have to figure out what to do based on a concern for both safety and performance, and will find there's almost always some kind of compromise!

Back to your bullets and their BHNs: it's been posted here many times over the years, but there's an old "rule of thumb" formula that says you need a minimum pressure to obturate the bullet properly to help avoid ONE of the many causes of excessive leading. That formula is 1422 x BHN = pressure. So your 17 BHN bullets would require about 24kpsi to obdurate properly. This formula's not carved in stone, but what you'll notice is if you're loading only 15-18kpsi (a bit warm for .38s, pretty mild for .357s) you could actually have bad leading problems cuz your bullets are loaded too lightly! Just the opposite of the "never drive 'em past 1000 fps" kinda recommendations often seen.

Do you have a chronograph? That'll tell you a lot: chrono your favorite factory ammo, then gear your loads toward duplicating it. Chances are you'll be able to find a satisfactory load w/o too much trouble...

Good luck!

Rick C

 

[JC676]

Downloading the 357Mags to that level should be no problem with those two powders. If your lead bullets are hard (which they are) you just have to find the right charge weight.

BTY hard cast bullet data is usually a little less than jacketed data. Softer lead bullet data is a lot less than jacketed data. But every case is different. The following start loads are close to what you were looking for I think.

From my Lee book:

158gr lead --- Accurate #5 --- 8.1gr ---1192fps --- 9.0gr Max --- 1354fps --- 39,100CUP

158gr lead --- Unique -------- 6.2gr --- 1188fps --- 6.8gr Max --- 1295fps --- 33,900PSI

I hope this helps,
...Jimbo[/quote]

Jimbo,

Thank you so much for the above info. That is exactly what I've been looking for... some guidelines to use with the hard cast bullets. The only manual I had that gave powder charges capable of producing the velocity I desired was a real old one (Speer #Eight) and I was very leary of using that data since I know lots of powders (including Unique) have been "reformulated" since that data was published.

I very much appreciate you responding to my post.

Regards,
Jon

 

[JC676]

Rick C.,

Thank you for such an informative post. I was under the impression that the only concern with lead bullets was potential leading if they were driven too fast. Obturation is new to me, but if lead "grips" tighter in the barrel than jacketed rounds do, I can see where that could cause pressure to rise.

Thanks again for responding.

Regards,
Jon

 

[flhr62]

I am guessing Rick misspelled on accident, but the word is obturate.

 

[Rick Courtright]

I am guessing Rick misspelled on accident, but the word is obturate.

Hi,

Oops... yes, it was accidental. I think I fixed it!

"Obdurate" describes MY behavior sometimes, not a bullet's...

Thanks for keeping an eye on me!

Rick C

 

[flhr62]

You are welcome Rick. I have read enough of your posts to know that you had just misspelled it. There is alot of misspelling on here including myself. Normally I would not even have pointed it out, but since JC676 had never heard of it, I thought he might want the correct spelling. Mark.

 

[tomiswho]

Wouldn't it be nice if a powder company would publish tables that indicate the BHN of the cast bullets? And have some for swaged and some for cast?

 

[Chief 101]

Wouldn't it be nice if a powder company would publish tables that indicate the BHN of the cast bullets? And have some for swaged and some for cast?

some reloader manuals specify alloy comp.

 

[GP100man]

A good guesstimate can be done useing the lee hardness tester , it gives a psi for the bhn measured .

If we know that the mean pressure is 35,000 for the 357 & ya gonna get 1350fps , then ya have a boolit bhn for 17,000 ya can look for 800 -900 fps before the boolit leads or strips .

I know it`s not an exact , cut & dried thing there`s just too many variables!!!!

BUT it`s a little better than a WAG !!!!

 

[Rick Courtright]

Hi,

While we're talking about the effects of hardness on leading, remember the lube being used can be very effective in preventing (or creating!) leading.

Most of the commercial cast bullets I've purchased have very hard lubes. I 'spose that helps 'em ship better, but they have to be driven harder to make the lube "work." W/ lighter loads, some have been pretty bad in the leading department.

At the other end of the spectrum, Ol' Elmer liked pushing his bullet pretty fast, and most of us who load the .44 Mag have heard of/and or used "Elmer's load" which is actually hotter than anything in today's books.

If memory serves, Elmer generally used a 16:1 alloy (16 parts lead, 1 part tin), which has a relatively high tin content, but isn't all that hard (antimony, missing from this alloy, is considered by most sources I've read to be the more important part of a bullet's alloy for contributing hardness.) W/ that bullet he also generally used a lube that was very high in beeswax (probably higher than the 50-50 alox mix we consider one of the "standards" today) and was pretty soft compared to most of those we use these days.

End result was he loaded some pretty warm stuff, yet never reported leading problems!

So we shouldn't toss out a change in lube as another of the possibilities when dealing w/ leading.

Rick C

 

[Chief 101]

I got lazy 4-5 years ago and bought some cast 44 cal boolits from Oregon Trail. They have the hard lube and bevel base. I got the 240 gr which I put out there at around 1400fps and the 200 gr one which I use at anywhere from 850-1200 fps. With about 500 rounds of testing and load development with these I did with these I never encountered any leading problems. Knowing the purposes for these lead slugs, I did have them sized properly. The 200's are .431" and the 240 are .430". I also have been casting for many years and use a lot of linotype and wheel lead in my own hardcast boolits. I still shoot 30 cal cast for whitetail hunting at 2kfps, no leading in the Winchester 94. There is a lot of good info on this thread and if you pay attention, good shooting with lead is possible and in my case most desirable.

 

[duct tape]

The rule for cast bullets is, don't shoot a soft bullet fast & don't shoot a hard bullet slow, so if you have good bullet fit in the throats & a bullet of correct hardness for the velocity you want, well, you are going to be a happy shooter.

Digging this old thread up to ask this question rather than starting a new one. Help a lead newbie - is the problem with shooting a hard bullet slow lack of obturation and then leading? or is it sticking a squib in the barrel?

Thx.

 

[Chief 101]

i

s the problem with shooting a hard bullet slow lack of obturation and then leading?

That would be my interpretation of the problem....others may disagree.