May I use the same powder (and the weight from the load manuals) as for jacketed bullets if I want to shoot gas-checked/lubed Cast Bullets at full velocities? (e.g. 416Rem at full velocities - 2350fps/400gr. through 2600fps/335gr.) I plan to use Beartooth bullets, which are heat treated to 22 BHN.



Any input is appreciated.



Art

Thats a tough question. First you need a good lube like LBT Blue or Rooster. A hard variation of Felix would be very good. Your boolits will need to be very hard. Find some cast boolit info and start there working up slowly to look for leading and loss of accuracy. Shooting a cast boolit too fast can raise pressures so keep an eye out for this too. Normally a cast boolit can be shot the same velocity as a condom bullet with less powder. I just don't know how fast they can be driven.
Do not reduce loads with slow powder and I can't stress this enough, it is DANGEROUS. This is why I say to look for cast boolit loads to start with, most likely with a faster powder. Once you determine what happens with high velocity you most likely will turn away from this idea.
I went through all of my books with no luck. If I were you, I would E-mail Hodgden or IMR to see if they can tell you what to do.
Somebody here might know too. BE CAREFUL! Thats a big case.

Art,

I know a lot of information was already covered in the reloading forum. Anyhow, here a few more things to consider. Are these loads for target shooting or hunting? The reason I ask is that my personal opinion is that a slightly softer alloy ~bhn 12-14 at 2000-2200 fps will likely work better on game then a harder bullet going faster. Then again, since it�s a 416, you won�t need much upset.

To get accuracy at higher velocities 2400-2600 fps, and no leading, there are several things that are necessary. First and foremost is a bullet fit to your throat and bore. This is often a problem with commercial cast bullets, as they tend to be sized to nominal bore size, ie .416�, instead of a few thousands over, which more barrels seem to prefer, but if you have a tight parallel throat, ie .4165�-.4170�, you won�t want the bullet bigger than the throat, as the round won�t feed. As Bruce mentioned in the other thread, slug your bore and get bullets sized appropriately.

The next item to consider is barrel twist. A slower barrel twist will allow higher velocities then a faster twist before leading. The engraving of the rifling is very violent on a cast bullet, and a faster twist will start sheering the bullet at a lower velocity then a slower twist. 1-12 twist barrels aren�t too rough on bullets, but 1-10 or even faster twists make life difficult. Nothing you can do about this, but something to consider.

Next thing to consider is the pressure of your loads, and the powder speed. Slightly slower powders have a (relatively speaking) more gently acceleration on the bullet, which is good for cast. High peak pressures are also rough on cast bullets, and if you can load under 50 kpsi, or better yet around 40 kpsi, you�ll have a better chance of getting good accurate loads that don�t lead.

Assuming you have bullets fit to your barrel, I�d work up to max loads and see how they shoot. If you are getting poor accuracy and leading, I�d suggest going to a slower powder, and lower your desired velocity by 100-200 fps, ie 400 gr @ 2200-2300 fps.

Good luck and let us know how it works. I think the bigger bores in general are a bit more forgiving when shooting cast. Some guns are easy to get good groups with cast, some you have to fight.

According to various CB manuals, firing a cast bullet of the same weight and bearing surface as a jacketed one using the same charge of powder, will produce lower pressure since the coefficient of friction of the CB alloy is less. With a properly fitted bullet to throat (leade) and a match grade bbl., accuracy is excellent up to ~2,600fps. ...Maven

Hello Art-

First - I'm not an "expert" but I have been at this for a while now. I'll relate my experience to date. I have been working on trying to match factory for a while now attempting to get my .348 Winchester up to "full power" loadings (read that equivalent velocities) as are published for Jacketed in equal weights.

My experience so far is that I have not been able to fully achieve the same velocities without pressure issues creeping in. I suspect bullet hardness & lube are contributors but I have not been able to get from here to there.

I went with slow burners (in the H4831 burning range) and started with slightly reduced starting loads for equivalent weight jacketed bullet loads. In my experience - reducing loads slightly for the slow burning numbers is not a problem, however these loads were still well over 75% loading density. I generally fired one to three shots over the chronograph and then started adjusting powder charge upward trying to get to full velocity. I can get close but in each case, extraction started becoming stiff before I got to the target velocity. In my example, I was trying to get 2200fps range which is listed as appropriate for a 250 gr. jacketed bullet. My cast bullet at 235gr., wearing a GC, 26BHN, and lubed with Gray's #24 gave sticky extraction at around 2100 fps. The same result for H4831, RL-19, and AA-3100. NOTE: The top velocities were achieved using less powder than most sources showed as the starting load for jacketed. In my case - the velocity where I observed sticky extraction with cast came at approx. 1/2gr. below the starting load suggested for jacketed. Based on this - I'd recommend backing off another 5% from starting jacketed loads when you start your development with cast.

I've pretty much decided to back off my desire to match the jacketed bullet velocity and live with a load that'll give me 2000fps without any potential for pressure problems. The difference in trajectory is negligible and my bullet has a large flat meplat so I think it'll do the trick in a hunting situation.

Good luck with your own efforts-

Sky C.

"May I use the same powder (and the weight from the load manuals) as for jacketed bullets
if I want to shoot gas-checked/lubed Cast Bullets at full velocities?"

Art, the main restriction will be pressure, obviously. Pressures generated inside your tube are
mostly due to inertia of the bullet, that is, the resistance to acceleration. Friction and twist
will also play a part, but the mass of the bullet is the prime consideration, safety-wise.

So, strictly based on the pressures involved, using load data for jacketed bullets will work with
cast boolits. Sort of. Whether or not the results will be acceptable for leading and accuracy is
a whole 'nuther story.

All the previous replies to your question are right on -- with caution and prudence, you CAN
use jacketed data as a starting point for your cast shooting, but be prepared to do more
experimenting with your loads. As you try different things, you'll find some combinations work
better than others, and eventually you'll find a recipe that is exactly what you want. When that
happens, it's time to either buy another mold and start again, or buy a new rifle! <GGG>

sky, that is exactly what I have found. Loading for the 45-70 using jacketed bullets at near max loads gives no problem, but if I try to aproach the same loads with the same weight cast boolits I can't extract the cases. Even though the friction of cast is less something happens to the boolit under so much pressure that it raises chamber pressure. I suspect it is inertia where the boolit doesn't move while it is being upset and shortened by pressure before it leaves the chamber. I too, see no need for such speed as I kill deer with revolvers and hard cast, large meplat boolits at around 1150 to 1500 fps and they drop faster then deer hit with 7mm and 30 cal magnums.

I don't believe that friction of the bullet has much to do with bore wear. It's erosion from hot gases, which cause chemical reactions with the steel causing brittle substances like carbides and nitrides to form, also producing hydrogen embrittlement, and very rapid differential heating and cooling of the surface of the steel relative to the underlying substrate, so the surface checks and flakes off in the area of the throat that's exposed to the most intense heat and pressure. (If it were due to friction, the wear would be worst at the muzzle, where the bullet's moving fastest.) The reason cast bullet loads usually effectively won't wear out a bore is that they're usually lower pressure loads than full house jacketed loads. Work up top pressure cast loads, with paper jackets or without, and I'll bet you find bore wear's about the same as with jacketed bullets.

�D?N?ul thanks for the contribution.

My intended use is for practice. I want to duplicate the handling of the rifle when shooting "real" (jacketed), very expensive DG hunting bullets - the recoil/muzzle-movement and, hopefully but less important, trajectory. And my justification is cost and barrel wear. Am I being reasonable?

To all who contributed, thank you all!!!

---

I think you do not understand Cast Bullets. First, You will not achieve the same recoil with the same bullet weight because 1/2 or more of felt recoil if from the jet effect of the escaping gas. Since there is less lateral resistance to a cast bullet as it is swaged and driven down the tube over the same weight jacketed bullet pressure will be less. The lower latteral pressure (friction) is the reason why you will not wear out a barrel shooting CBs. Second. The barrel vibration of the two bullets will be different as there is less torque hence a different point of aim. Third trajectory of the bullet in flight is affected by the bullet shape, you can get cast bullets in the shape of a spitzer (I have one and it is not my most accurate) most companies do not make a spitzer look alike you may find a round nose that will come close. You can shoot most any cast bullet at factory velocities if you wrap them twice with Teflon tape (see Handloader #86 July/Aug 1980) they achieved accurate results at 2700 fps with 30/30, 45/70 .243 7X57. I would suggest you consider cast as a different game that will give you different feel and performance from your rifle. As noted you can patch with paper and shoot with less wear than jacketed, cast with lube is a third choice. Review your expectations and you may find you may enjoy the differences. There is a french phrase for this but (blank) the french. JB

Ricochet, of course you are correct with your comments on throught erosion and pressure. My comments were broad and include shooting older arms with softer steel than today that have over the course of years been shot out with normal loads with jacketed bullets. Barrels described as "sewer pipes" and such. I think it is fair to say that an older collectable arm would maintain what rifling it has with cast bullets even at higher pressure. The effects of pressure and friction are degrading to the bore, I do not know the proportions between the two, No argument that pressure and heat are the most aggressive. There are a lot of older barrels out there with little rifling that shot more or less weak loads by todays standards. I think some of the wear must be from friction. JB

I agree with bfrshooter, grumble said it all. To that let me just add that with the .458WM shooting 485 and 500 gr boolets at full velocity (2100fps or so) there's virtually no difference in velocity or perceived recoil between cast and solids. Most I've done was about 50 in one session. Hurt for over a week. My friend did about 30 in that session - brused black and blue for that week.

Maybe so but I'll add this anyway. Paper patching eliminates leading within reasonable velocity ranges, say hard cast up to about 3000 fps, dead soft or 1:20 maybe 2200 fps or so. Your .416 is likely a good candidate for this due to slow twist rate. I'd guess, and it is a guess, that Lyman # 2 or harder would do find at full velocity regarding accuracy and leading. JMO

Grumble, very well said! Nothing can be added, you said all that needs to be said.

JB, a new perspective on the subject. Thank you. I love this forum, and all you wonderful folks!!!

Art

Art, now you've moved into the realm of opinion. We excell here!

When you're hunting and shoot at an animal, you will just barely notice the recoil or noise.
More like, you notice it, but only incidentally to what you're concentrating on, the animal.
Of far more importance is your aim. You need to know what the particular load you're shooting
will do at the range you're shooting it, and you need to be thinking about windage and elevation,
not recoil.

So, as for opinion (ahem), I'd think that you'd be wanting an accurate load to practice with,
irrespective of recoil. Once you're good with your rifle, it is a matter of only a few rounds
to sight in with the bullet you intend to hunt with. What you'll be lacking, though, is a good
understanding of the ballistics of your hunting round. Cast boolits are usually less efficient
aerodynamically than similar weighted condom bullets, and as a result will perform differently
especially at longer ranges.

IMO, how you hold the rifle and your confidence in being able to hit what you aim at is of
paramount importance in a hunting situation. I don't know your intended quarry or how
special the particular hunt is to you. (I mean, a safari to bag a water buffalo is a lot different
than a deer hunt in the next county.) You'll get the rifle handling techniques down just fine
with practice and cast loads tuned to your rifle. And if you're going for medium game like deer,
the good load you develop for practice will probably be just fine for hunting with a boolit of
that caliber. But, if the hunt is really special, and you want to use the expensive jacketed bullets,
plan to spend a few bucks to learn how they fly. Nothing is harder on the ego than a missed shot
-- don't ask me how I know. <GGG> It can keep you awake for a week thinking about what you
should have done.

In sum, it's possible, but unlikely, that you can match both the ballistics and the recoil of a jacketed
bullet with a boolit. What you CAN do, is become an expert with your rifle with cast, and then
reload and relearn how to shoot it with jacketed.

Art,

I figured that was what you are after. You might not be able to get the accuracy at full patch levels. Personally I'd go for a nice accurate slightly slower load. While the recoil won't be totally identical, it should be close enough. You might even find the loads hitting lower then jacketed loads.

You're after "becoming one with the rifle", and you can do that well enough with 400's @ 2200 fps. You won't notice the increased recoil when hunting. You will notice that you've fired hundreds of rounds through the gun and know how to shoot it. Within 200 fps, trajectory will be within 1-2" out to 300 yds, and pretty much spot on inside 100 yds. Just get a good load, sight as you will for jacketed, and practice a bunch.

I think most folks will agree that it isn't that hard to get a good cast bullet load that is within a couple hundred fps of a jacketed one. Being able to take full pressures in a magnum round can be done, but may require a bunch more fiddling. I'm a lazy caster and loader I like to have easy to make reliable loads. If I have to give up a few fps in the process, so be it.

Paul thanks for the contribution.

My intended use is for practice. I want to duplicate the handling of the rifle when shooting "real" (jacketed), very expensive DG hunting bullets - the recoil/muzzle-movement and, hopefully but less important, trajectory. And my justification is cost and barrel wear. Am I being reasonable?

To all who contributed, thank you all!!!