Cast bullet in place of jacketed. Dangerous?

[Jaak]

I could not find an answer to this question with any quick Googling so I'm asking here.

Can you substitute a cast bullet in a recipe that calls for a specific jacketed bullet as long as the mass of the bullets are the same?

I understand that driving a cast bullet to jacketed speeds will cause leading very quickly and that it may not work worth a damn because of many different factors involved, but will things explode?

I'm asking because I cast a bunch of 158grain bullets but they all came out in the 160grain range. I can't find a recipe in my books for a cast 160grain bullet with the powder that I want to use, but I can find one for a jacketed 160grain. Would there be any harm in using the jacketed bullet recipe with the understanding that it may not be ideal?

[jim147]

Unless you are using a powder that has the same start and max listing just start at the lightest load for the 158 and work up from there. Those 2 grains of bullet weight won't even be noticed.

[44Blam]

You can use jacketed data for a basis. Just start low and chrono the rounds to make sure that you are getting the velocities that you expect.
Ultimately, the thing to keep in mind the case volume. So if your COL is the same and the bullets are a similar shape, the data is probably pretty close. If your COL of your lead bullet is shorter, you need to start with a lower charge because the reduced case capacity will generate higher pressures.

[Larry Gibson]

Jaak

This question comes up frequently, i.e. "can a cast bullet of equal weight to a jacketed bullet use the jacketed bullet data", or visa versa. I've done a lot of pressure testing of various cartridges, handgun and rifle, attempting to answer that question. I've not come up with a definitive answer and I really don't expect to. There are just too many variables such and jacket hardness, alloy hardness, actual bearing length and seating depth (not to be confused with the OAL of the cartridge), etc. In pistol/handgun cartridges the seating depth appears to be the critical factor, not necessarily the weight of the bullet.

Additionally I've found that with a given cast bullet varying in weight by a few grains there isn't as much difference in pressure with a given load as we might assume. My suggestion is; if you have data for the bullet you are using then use that data regardless of a slight variation of bullet weight. As always start low with the 'start" loads for that data and work up.

[fredj338]

If you want a safe answer, it depends on the load data. At max, everything you change matters. So I would never plug a cast bullet into a max jacketed load without dropping & working it back up. If your jacketed load is midrange, swapping cast for jacketed in the same weight isnt going to affect things much. OAL & bearing surface will matter more.

[tankgunner59]

I had that same question about my Winchester Model 94AE. With good advice here I emailed my question to Hodgdon and a tech answered the next day that the start load in my manual would work with the 8202 powder. So my advice is to contact the powder maker and pose your question, be as specific as you can.

[Mk42gunner]

It also greatly depends on the cartridge. Normal handgun rounds (even from a rifle) you are probably okay, high velocity rifle rounds may be a very different story.

I will say that I don't think I have ever had a mold drop a boolit to the advertised weight, even when I was using the designated alloy.

Robert

[243winxb]

Use lead data from 158 gr. https://www.thehighroad.org/index.ph...d-bullets.265/ lead vs jacketed.

[Land Owner]

Harm? No harm.
Probably a lead dust cloud at your muzzle when pushing a lead boolit at jacketed bullet velocity.
Hammering the air with an unshielded lead boolit - at jacketed bullet speed - is a waste of components.

[JonB_in_Glencoe]

maybe share some specific details, like what powder and what caliber and the load.

[243winxb]

More from link

[reddog81]

For all intents and purposes a 160 grain lead bullet is a 158 grain bullet. Bullet weights can vary due to alloy content.

I’d be more concerned about variations in load data due to different bullet shape/profile than 2 grains of lead.

[P Flados]

In recent years I have become convinced that case fill % or load density is the most important variable for getting results that are consistent with published loads where you are going to make a component substitution. As noted by Larry Gibson this is not just OAL. Note that in addition to seating depth, variations in case capacity can also affect fill %.

I also agree with Larry in regard to bullet weight being a "minor" variable in the puzzle. Batch differences in powder probably matter more.

However, even when you ensure you are not exceeding the published load fill %, the other variables are still there and can potentially stack up to cause problems. This is where the "start low and work up" comes into play. However, in a lot of applications (see case 3 below) I feel this does more for a "feel good" thing than actually protect your gun.

Case 1: If your gun can handle pressures that will stretch primer pockets without hurting the gun (good bolt actions, TC Encore in 30-06 or smaller diameter brass, etc), working up loads while watching primers is a no big deal kind of thing.

Case 2: If your gun shoots a 55,000 psi cartridge the same or bigger (case diameter) as your cartridge, working up loads while watching primers is still ok, but requires more care. You may be getting in to "proof load" stresses on your gun before you decide your primer looks bad. I recommend backing off a little from the max load that looks OK for your regular loads in this situation.

Case 3: The gun is of a lower pressure rating than case 2. I do not feel that watching primers has near as much value as many seem to think. Unless you can figure out exactly how much pressure your chosen primers require to flatten (a tid bit probably only known by primer makers), why should you assume it to be any less than 70,000 psi (5k above the highest pressure applications your primers can be used in).

Sticky cases are also bad thing and you can bulge a cylinder about the same time you notice sticky extraction.

If you are into case 3 and you feel your gun is stronger than the average gun made for the caliber, loading up to "book max" is probably reasonable provided your components match pretty good with the load data and your fill % is less than the published load. However, to the extent possible only use recently developed data with pressure values in psi or data otherwise known to be conservative.

If you are into case 3 and you want to be on the safe side, just plan on staying below "book max" and keep your fill % is less than the published load.

[Hanzy4200]

My experience, handgun yes, rifle no. Like mentioned, start on the low side. Cast actually will get higher velocity than the same charge on jacketed. Better gas sealing. To an extent.

[Soundguy]

Unless you are using a powder that has the same start and max listing just start at the lightest load for the 158 and work up from there. Those 2 grains of bullet weight won't even be noticed.

Fully agree.

[45DUDE]

I agree with post 2 & 4. When I get through casting I fill my pot back up and check to see what the boolit weighs and add what is needed for the mix for fine tuning. What ever the boolit weighs I adjust the powder charge. I made a 148gr wc weight 136gr just to see if I could.

[mdi]

I believe the definative answer is Mr Gibson's post. The last sentence of Mr Gibson's post is the key to any extrapolation/experimenting...

[Burnt Fingers]

You're getting yourself all twisted around the axle for no real reason.

2 gr difference in boolit weight isn't going to make a bit of difference...in a nominal 158 gr boolit.

I don't even bother to weigh my boolits. If the mold says it's a 200 gr boolit I use 200 gr data and forget about it.


A little-known fact here. The famous H&G 68 boolit that's supposed to be a 200 gr actually comes in closer to 210 gr.

[GregLaROCHE]

I’ve often started with starting loads for jacketed bullets, but made sure my alloy was fairly hard. From there you can start working up. Always keep on top of sighs that are going well.

[1hole]

Your question is a good one but reloading is more of an art than a science. I mean, we really can't make many iron clad statements about much of anything without personal testing.

BUT:

1. - I've been doing this since 1965 and my experience has told me that cast loads will always be at a lower pressure and higher velocity than a jacketed load with the same powder charge because no lead alloy has yet been made that equals the hardness of a jacket. Well lubed lead bullets tend to slide through the bore easier/faster than jacketed bullets of the same weight and powder charge.

2. The only high pressure cartridges (for common handguns) that I know of are the 9mm and 10mm; they are quite touchy to small changes because of their high pressures and small cases. All other cartridges are far less twitchy at their upper limits. Thus, normal variations in cast bullet weight/shape/hardness such as yours can safely be ignored.

3. Normal small seating depth/OAL variations (say, maybe +/- 50 thou) from book data for moderate and low pressure/small case handgun cartridges (i.e., all but the 9/10mm) are virtually meaningless. I set all of my bullets and boolits so the crimp groove is right and shoot them without even checking a book OAL.

NOTE: That does NOT mean insane variations in seating don't matter. Just don't seat so a hot loaded bullet nose is flush with the case mouth (unless it's a full wadcutter and no one loads them very hot) and you'll be okay. I have to say all this because someone always jumps in to say that some folk will do some crazy things like burying a bullet so deep it compresses the powder charge and then blame others for their own stupid results if things go wrong!

4. Trying to gage excessive chamber pressure by looking for primer flattening is equal to a witch doctor examining the entrails of a chicken; meaning that flat primers rarely tell us anything useful. Flattened primers were somewhat helpful back when most of them were convex but I've not seen any new dome top primers since the mid sixties. Since then primers come to us with flat tops so we can easily blow our guns from together if we are expecting flat primer tops to warn us. But, legends die hard and looking at primers sounds good so it's easy for it to keep it going. ??

(Most truly flattened primers are caused by excessive headspace anyway; if the headspace is right it takes a LOT of over pressure to do much more flattening than the makers!)

The ONLY signs of over pressure I trust in a revolver is sticky cases and/or pierced (blanked) primers; THOSE are sure signs of over pressure!

MY top charge limit for autoloaders is my books. Even tho some book charges are too much it's very uncommon for a book load to produce a KABOOM! the first time it's fired! BUT, not all guns have read all of my loading books so I strive to stay aware of things like perceived recoil and how/where the ejected cases land. Nothing good comes from reloads at the ragged edge of safety so I'll immediately stop and back down a bit if things don't seem right.

So far, in my five plus decades of reloading for a lot of guns in a lot of cartridges, I've never had an accident and only a couple of instances of getting a little too hot. One was a too happy old Lyman book max charge of Unique under a 250 grain SWC fired in my S&W .44 Magnum. The recoil was sharp and I'm not gonna tell you what my chronograph said but Elmer Keith would have been proud of me! The R.P. cases were stuck pretty tight so I backed off ... way off.

My rambling point is, there are too many variables in guns and components for anyone to honestly tell you anything in much detail or with much accuracy. Just stay well within the envelope and you won't need to get uptight about small bullet differences. Until you have at least a few hundred rounds of experience with your new bullets stay well inside book powder charge limits and even then don't trust the books completely. After you learn what to expect with known safe loads you might want to creep your charges up in small incraments, like maybe in .2 gr. steps.

At the end of the day, reloading safely isn't memorizing and following an infallible list of lock-step dos and don'ts. It's mostly incremental experience thoughtfully tempered with patient common sense and a total concentration on each step as it's performed at the bench and fired at the range.

Good luck!

"Let's go Brannon!"