FMJ to Lead conversion

[MoreIsLess]

I am thinking about buying some lead bullets next time and loading them instead of FMJ. Problem is the load data tables don't have any listing for the lead bullets I want to use although they do have listings for FMJ's of the same bullet weight, caliber, type. Would the powder weight charge be the same for a lead bullet as for a FMJ if the bullet weight, shape, caliber and everything else was the same?

 

[LiveLife]

I always try to use lead load data for lead bullets as they can vary quite a bit from jacketed load data. I usually reference Lyman #49 reloading handbook also as it has a lot of lead load data.

Hodgdon website has quite a bit of lead load data for Hodgdon, Winchester and IMR powders - http://data.hodgdon.com/cartridge_load.asp

Accurate load data has a lot of lead load data.

Alliant website don't list much lead load data for 9mm and 40S&W but there's plenty of lead load data in 2004 Alliant load data and more lead load data in 1999 Winchester load data.

 

[Salmoneye]

Try these:

http://www.handloads.com/loaddata/

http://www.reloadersnest.com/

Use at your own risk, and always work up to any published max...

 

[LiveLife]

Use at your own risk, and always work up to any published max...

Be careful when using some loads listed on handloads.com with "guest" as source as they are user max loads and not published load data max loads.

I would highly recommend you conduct powder work up using published load data or loads verified with published load data, not merely "internet posted" loads.

 

[RedHeadHunter]

+1 on the Lyman.

Lead requires a different load because it requires a different amount of force to push it through the barrel, this causes different pressure curves. The latest Lee book has a really good section on pressures vs accuracy with lead bullets.

I usually load lead for my light plinking loads. I don't load them hot because lead is a pain to get out of a barrel.


Just for a little more info. some jacketed bullets with coatings or driving bands (Remington Golden Sabre) have less barrel resistance and can usually be loaded a little hotter and get a few more FPS. Some load books have loads specifically for those bullets.

 

[jcwit]

I use the Lyman Cast Bullet Manual.

With that said, I also use other manuals with the loads for jacketed bullets and load light and work up a load from there. Remember lead alloy used and still is used as a bearing metal for many applications. Its much easier to start and send a lead bullet down the barrel than a jacketed.

Also if one uses the correct size bullet, correct lead hardness, correct lube, and correct charge, there is no issue with leading.

And if you do have an issue with leading, wrap a few strands of copper Chore Boy pot scrubber around a worn out brush and a few passes thru the bore is all it takes.

 

[ArchAngelCD]

NO, you should not use the same data for lead bullets that is listed for jacketed bullets. Lead bullets will usually use less powder, sometimes a lot less powder. Be very careful not to cause an overpressure problem.

Like said above, Lyman #49 has a good amount of lead bullet data but the Lyman 4th Edition Cast Handbook has even more. It's not just a reprint of the data in Lyman #49, there is a considerable amount of additional data in the Cast Handbook. For the first time in Lyman history they list data for molds other than their own. It's highly recommended, I wouldn't be without it!

 

[56hawk]

Personally, I have found that any data that is safe for a jacketed bullet is safe for a lead bullet of the same weight. Of course you may get leading with the wrong combination, but I don't think you will have any pressure issues.

 

[ArchAngelCD]

Personally, I have found that any data that is safe for a jacketed bullet is safe for a lead bullet of the same weight. Of course you may get leading with the wrong combination, but I don't think you will have any pressure issues.

I'm sorry to say that is incorrect. You can generate excessive pressures if you use jacketed load data with lead bullets.

Current data on the Hodgdon load data site shows a Max charge of 4.3gr W231 with a 158gr Hornady XTP bullet whereas a Max charge of only 3.7gr is recommended with a 158gr lead bullet. The spread is even greater in the .45 Colt. Pressures can spike with some powders even with slightly higher charge weights so it's really not recommended to use jacketed data with lead bullets.

 

[Walkalong]

As ArchAngelCD posted, no, lead data is different.

Use 5.0 to 5.5 Grs of W-231/HP-38 with any 12 to 14ish BHN (And sometimes higher) lead 200 or 230 Gr RN bullet loaded to 1.260 OAL and all will be well. A good starting point for shooters new to lead.

 

[56hawk]

I'm sorry to say that is incorrect. You can generate excessive pressures if you use jacketed load data with lead bullets.

Current data on the Hodgdon load data site shows a Max charge of 4.3gr W231 with a 158gr Hornady XTP bullet whereas a Max charge of only 3.7gr is recommended with a 158gr lead bullet.

But notice that the 3.7 grain charge is 1,300 CUP lower pressure than the 4.3 grain charge. Also Lyman lists 4.9 grains with a 160 grain lead bullet, of course with an additional 900 CUP of pressure above Hodgdon's jacketed data.

 

[Walkalong]

Some data overlaps, and yes, often times they stop short of max pressure with lead data for various reasons, but to blankly say all jacketed data can be used with lead is incorrect.

 

[56hawk]

Obviously anytime you change any component from a published source you are going to get different results. Does that mean you always have to use the same exact bullet, case and primer to be safe? I don't think so. And I have never seen much of a difference between jacketed and lead bullets of the same weight.

 

[LiveLife]

I try to duplicate the components in the published load data but often cannot as I buy different bulk component items. So I come as close to as I can on bullet type/nose profile so I can have comparable bullet base seating depth, which I consider significant for matching chamber pressures. Of course, using a chrono to measure muzzle velocities will give you the most amount of comparative data to the published load data, but if you shoot at an indoor range, you can't always set one up.

If I am using shorter OAL than published load data (or I have a good idea that the bullet seating depth is deeper), I will often use .2-.3 gr less for start/max powder charges.

As Walkalong posted, some jacketed and lead load data are comparable or same, but it would be safer reloading practice to observe the differences, and they often are.

Be safe.

 

[GT1]

I think the reason lead is loaded lighter is because it is not as durable. Loading to FMJ pressure will(might) lead the barrel, or (might)make the bullet come apart before getting far, generally. I don't think it has anything to do with overpressuring the chamber.

It has already been pointed out that is a bearing material(slides in the barrel easier) and it is higher velocity for a given charge/weight, that contradicts the more pressure situation.

I'm betting it has everything to do with durability of the projectile.

 

[LiveLife]

GT1, no, no and no.

Everyone shot lead bullets in their pistols and rifles until full-length gas checked bullets came along (aka jacketed bullets).

Magnum range lead bullets like .44 Mag are shot without the concern for bullets coming apart.

Leading is result of various factors and covered in detail in this chapter - http://www.lasc.us/Fryxell_Book_Chapter_7_Leading.htm

Glen Fryxell wrote an excellent e-book on lead bullets that is a must read for anyone who wants to get the most out of lead loads (I highly recommend it) - http://www.lasc.us/Fryxell_Book_Contents.htm

 

[homatok]

I'm with Gt1 on this. It is generaly accepted that you can safely use the STARTING load for a similar weight jacketed bullet as the starting load for cast and then work up! If you have no comparable jacketed bullet take the starting load from the next heavyest jacketd bullet as your starting load, i.e. 180 jacketed bullet to get starting load for 170 cast.

 

[GT1]

GT1, no, no and no.

Sorry, no, no, and no aren't valid answers, and those books aren't what we are discussing here.

We are talking about why it is bad to use FMJ data for lead projectiles and how they compare(Read the title). I gave a reasonable answer. I call BS on same charges and projectile weight causing higher chamber pressure just because it is lead.

No worries, though.

Until a ballistics scientist explains that it is so, I will go with my instincts however.

 

[jcwit]

With that said, I also use other manuals with the loads for jacketed bullets and load light and work up a load from there. Remember lead alloy used and still is used as a bearing metal for many applications.

Anyone notice how I phrased this, start light and work up from there?

but to blankly say all jacketed data can be used with lead is incorrect.

I agree with walkalong, and I'm sure he'll agree that I did not make a blanket statement regarding using jacketed data versus cast data.

Actually, blanket statements very seldom hold much water.

 

[LiveLife]

Sorry, no, no, and no aren't valid answers, and those books aren't what we are discussing here.

We are talking about why it is bad to use FMJ data for lead projectiles and how they compare(Read the title). I gave a reasonable answer. I call BS on same charges and projectile weight causing higher chamber pressure just because it is lead.

Fair enough. So, let's compare some load data.

I dug through and looked for jacketed and lead load data that used the same nose shape bullets (FMJ vs lead RN). 1999 Winchester load data lists the following for 9mm 124 gr FMJ/LRN and 45ACP 230 gr FMJ/LRN:

124 gr FMJ W231 Start 4.2 gr (1005 fps) 28,800 PSI - Max 4.5 gr (1060 fps) 32,700 PSI

124 gr LRN W231 Start 3.3 gr (910 fps) 23,800 PSI - Max 4.0 gr (1035 fps) 32,900 PSI

230 gr FMJ W231 Start 4.9 gr (695 fps) 14,900 PSI - Max 5.7 gr (830 fps) 19,200 PSI

230 gr LRN W231 Start 4.5 gr (765 fps) 15,500 PSI - Max 5.1 gr (870 fps) 19,800 PSI

If you compare the FMJ and LRN load data, you will note the max chamber pressures are comparable but the powder charges used are not.

No worries, though.

Until a ballistics scientist explains that it is so, I will go with my instincts however.

That's your choice. But I think there's a reason why they publish separate load data for jacketed and lead bullets.

 

[Walkalong]

I think the reason lead is loaded lighter is because it is not as durable. Loading to FMJ pressure will(might) lead the barrel, or (might)make the bullet come apart before getting far, generally. I don't think it has anything to do with overpressuring the chamber.

I agree with bds, it has nothing to do with the durability of a lead bullet.

Sometimes they stop short of full pressure loads with lead because they are target loads with soft lead, and yes, to much velocity with soft lead can strip the rifling in many barrels, causing leading, but it is nor a durability issue, it is a strength issue with soft lead and holding the rifling. Rifles that shoot soft lead at high velocity use deep rifling.

With a higher strength alloy, lead bullets can take everything the .44 Mag or .500 S&W can dish out.

You are right in one respect, that to much pressure with the bullet listed that they stop short of high pressure with, can cause leading, due to what I described, but it is not because the bullet comes apart, it is simply because it is too soft to hold the rifling at that speed. It is a speed thing. The pressure is trying to squeeze the bullet harder into the rifling. That helps, but the soft alloy just can't take the velocity.

We are talking about why it is bad to use FMJ data for lead projectiles and how they compare(Read the title). I gave a reasonable answer. I call BS on same charges and projectile weight causing higher chamber pressure just because it is lead.

I do not need to read the title, as I am aware of the question at hand. Your answer of bullets coming apart was a "reasonable" guess. It just happened to be wrong.

jcwit described a good way to approach interpolate using jacketed data with lead. (My bold)

I use the Lyman Cast Bullet Manual.

With that said, I also use other manuals with the loads for jacketed bullets and load light and work up a load from there. Remember lead alloy used and still is used as a bearing metal for many applications. Its much easier to start and send a lead bullet down the barrel than a jacketed.

Jacketed data with lead bullets is not always safe. Often times? Yes. Always? No. Period.

Excellent post bds.

 

[StrawHat]

MIL,

Specifically, for what cartridge do you need data?

 

[Salmoneye]

Be careful when using some loads listed on handloads.com with "guest" as source as they are user max loads and not published load data max loads.

I would highly recommend you conduct powder work up using published load data or loads verified with published load data, not merely "internet posted" loads.

I fully agree, and always cross check before I use any load from that site...

 

[Steve C]

There are several issues with lead and the reason data specifically for certain lead bullets can vary quite a bit. First thing to note is that the load and bullet weight being equal lead will shoot faster than jacketed as lead has lower bore friction resistance.

With softer lead bullets load data will often be much lower than jacketed data as will the velocity to avoid bore leading by pushing the bullet too fast. Speer and Hornady data is generally lower as their bullets are swaged and relatively soft compared to hard cast.

Data you find in the Lyman book for cast bullets is generally higher at the max end than the Speers or Hornadys data with velocities equaling jacketed bullets but the top loads are lower charge than the same weight jacketed bullets producing similar or equal velocity. With harder cast bullets light loads can produce excessive leading. If casting your own you can often adjust leading issues with adjust the size of your bullet. When using commercial cast you are stuck with what you buy or can order so obturation of the bullet base by increasing load pressure is often only choice to prevent leading.

Its been my observation that even the most optimistic loads for lead generally max out at approximately the start level of10% below the max loads for equal weight jacketed bullets. Thus a 20% reduction of jacketed data gives you a fairly reliable start load for lead bullets that are relatively hard while not exceeding a maximum lead load of 10% reduction from jacketed bullet max charge. If you are using a swaged or softer cast bullet then further reduction may be needed if there is excessive leading. When you are not using exact data for your bullet, load development becomes more inportant.

 

[earplug]

I have had good results using the Winchester online data. There is lots of data for lead and jacketed bullets.
My older manuals usually state that the lead loads are limited due to leading etc. My Hornady and Speer manuals use their Swaged lead bullets which are not as capable of the velocity/accuracy as the jacketed bullets the companies sell. I think only Lyman's manual has data on cast bullets. Of course various lube, hardness and bullet size have much varience on pressure, velocity and leading and accuracy. I have shot cast bullets from 356 to 360 in the same revolver. Depending on what I wanted the bullet to do they all worked fine.
A cast bullet is very capable whan all factors are considered. A jacketed bullet will give a quick easy solution at considerable more cost.