Frosty versus Shiny

[grumpy one]

I used to try for shiny bullets, either because they look nicer or because Lyman says they are best. Recently I cast a batch of frosty ones, letting the moulds heat up then keeping them that way. On limited data so far, I now think frosty is better.

First, consistency of weight. I got shiny bullets while the moulds were warming up, and when I inspected and culled, then weighed and categorised the bullets I found the good-quality shiny ones were at least one grain lighter (175 and 180 grain bullets) and had greater weight variation. I finished up rejecting all of the shiny ones because of this. The hot-cast frosty ones fitted into a weight range of 0.2 grains - I ended up abandoning the weighing process as a waste of time.

Second, consistency of hardness. All bullets were air cooled. Four weeks after casting, using an alloy that is probably 1.3% tin, 5% antimony, I tested five each of shiny and frosty bullets. The shiny bullets averaged 24.5 BHN, standard deviation 4.9. The frosty bullets averaged 13.6 BHN, standard deviation 1.9. In other words, all of my air cooled shiny bullets were effectively quench-cast.

There needs to be more work done on this, including seeing what the hardnesses are after a year rather than a month, and using larger sample sizes, but at the moment I'm disinclined to use shiny bullets in future - it's quicker to put them back in the pot right away, than it is to weigh them first and then do the same thing.

[buck1]

Frosyt boolits stay liquid longer,there by have less air voids.
If its not evenly frosted its not mine. ...Buck

[Bass Ackward]

GO,

What ever floats your boat. Question is what does it get you?

I have taken bullets in 30, 35, 44, and 45 calibers and tried pretty much everything. It seems that as long as you have enough velocity to stabilize them at the twist rate you are running then it doesn't make too much difference.

In other words a 45 caliber, 400 grain bullet a 1400 fps that weighed 8 grains of difference shot identically to good bullets in a 14 twist, but did open some in a 20 twist. There the 14 twist held the accuracy edge. At 2100 fps, both shot equally well from both twist rates this time, but the 20 twist stepped to the front over all.

Might say the same about marginal designs. Marginal bullet designs need to be better bullets to shoot well. A good design that is stabilizing easily might have more room for error.

Hard to imagine how the same mix that could only be 25 degrees difference between shiny bullets and frosted ones could end up that far apart in hardness. I've had my bullets grow in diameter, so maybe we need to mix a batch of your stuff and mine together and see what happens. :grin:

[grumpy one]

Bass, I have been having group-size consistency problems, and I'm trying to minimize the variations in what I'm loading. Every group I shoot is with deburred neck-turned weight-matched cases, using individually-weighed powder charges. Groups at 55 yards vary from MOA (very rarely) to three times that (equally rarely). I've tried relatively hard (24 BHN) and relatively soft (13 BHN) without seeing any effect on the variability of group sizes. Sorting the bullets into weight classes also had no visible effect (at 55 yards - might be different at longer ranges). I've tried a few powders, and I'll have to try more. I have only tried two bullets, both bore-riders (311291 and 309-170-F), and so far it seems the rifles prefer the one with the better-fitting nose, but the difference isn't all that much and the variability is there either way.


I have it in mind to try more consistent bullets, and a couple more powders, and if I still don't get anywhere I may become desperate enough to buy more bullet moulds. So far is the primary influence seems to be choice of powder.

[Lloyd Smale]

theres a real fine line between bullets that are frosty and bullets that are not filled out. Especially in steel molds with big caliber bullets. Hot spots show up on the bullets where the two cavitys are closest in the mold blocks. This is more prone to happen with steel molds and high tin alloys. I like to run my molds to drop shiny bullets and keep the temp right at the edge of frosting. Only exception is aluminum molds which seem to cast better hot.

[hivoltfl]

I'll take mine on the frosty side for all the reasons grumpy one stated.

Rick

[Bass Ackward]

1. Bass, I have been having group-size consistency problems, and I'm trying to minimize the variations in what I'm loading. Every group I shoot is with deburred neck-turned weight-matched cases, using individually-weighed powder charges.

2. Groups at 55 yards vary from MOA (very rarely) to three times that (equally rarely).

3. I've tried relatively hard (24 BHN) and relatively soft (13 BHN) without seeing any effect on the variability of group sizes. Sorting the bullets into weight classes also had no visible effect (at 55 yards - might be different at longer ranges).

4. I've tried a few powders, and I'll have to try more. I have only tried two bullets, both bore-riders (311291 and 309-170-F), and so far it seems the rifles prefer the one with the better-fitting nose, but the difference isn't all that much and the variability is there either way.


Grump,

1. I understand. Figured that was where you were headed. Been down that path many times. Now I only do that extra stuff after I found what I want.

2. This is hard to interpret. Depends on so many things like what firearm and the conditions.

3. Uh huh. No difference from hardness? No difference from weight? Are you choking? If so, it is mandatory that you mold better bullets. Since most bullets are base pour, air is trapped in that area making them vulnerable to it. Longer bullets especially. Bullet deformation occurs as these are closed by pressure swagging and your base moves unpredictably out of square. That's why I also like light bullets per caliber, since weight effects are accumulative on the base and they are easier to mold well. No heavier than needed to reach the lands. Oooppps, that eliminates bore rides huh? :grin:

My results are that the more you try to shove in that little hole, the better your bullets need to be which may result in better average grouping over all, but the wilder your fliers will be.

4. Something to think about. Very few powders are going to take you from 3" at 50 yards, to 1/2". Pick one logical cast bullet powder for rifles like say 2400 to 4198 or equivalents. In other words, I can't go from 2400 to 5744 and expect a major difference. You may need a bold move. You may need a filler. (I hope not too many people read this) But I would stick to one powder until I isolated the problem and reached consistency. Then change powders.

You may be on the right track about your bullets if voids have been the problem for you.

[44man]

If you are getting good shiny boolits, cast the right way and are just short of frosty, that boolit will be a little lighter then a full frosted one because the hotter mold has expanded more and drops a little larger boolit. I would not call the little weight difference a void in the boolit.
When a mold is colder and lead is just dropped in so you depend on the shrinking boolit to pull from the sprue, you will get all kinds of bad boolits. The sprue will start to set up before the boolit can draw in lead from it. Thats why most guys get better boolits when frosted because the sprue stays molten a little longer.
I use a ladle and I hold it tight on top of the mold so the boolit will draw from the ladle, not the sprue. The larger the boolit, the longer I hold them together. You can actually see the lead in the ladle drop as the boolit starts to set up.
If you are pouring the lead stream through air into the mold, you need the mold and lead very hot so the sprue does not set up before the boolit or at the same time. The sprue has to stay molten longer then the boolit! What you have is a very short work window and casting speed is critical. It makes guys cut molten sprues to keep up. The boolit is also still dead soft and can be forced sideways in the cavity with the sprue plate, what happens to the soft boolit when dropped out of the mold? Not to mention lead buildup on top of the mold and bottom of the plate.
I teach a lot of friends to cast and I will tell you the truth---Some guys have ten thumbs and no coordination. It takes me at least an hour before they start to get good boolits. Some don't get it after a year! And what a mess they make, lead all over the place.
Bass is right about powder. Most that apply to the caliber will give decent enough accuracy to find the right boolit, then try different powders.
I am not fussy about shiny or frosted or a tiny weight difference and not even a little difference in hardness and I shoot cast as good or better then jacketed. bullets.

[SharpsShooter]

Another vote for the frost variant. They vary far less regarding weight and diameter than their shiny brothers and if you don't like the frosty appearance, give em a quick swipe with a paper towel and no one can tell the difference.


SS

[44man]

I leave the frost! I think the lube holds better to it.

[1Shirt]

I agree with 44Man!
1Shirt!

[LAH]

I always sold shiny bullets. If you want them frosty be sure they are the same all over. When you frost in spots as Lloyd said you will have a void or perhaps an out of round bullet.............

[axman]

Ill vote for frosty with my lbt moulds and w-wts I've got several 3 shot groups at 100 yds between .625" and .812" in 45-70s, scoped & open sights.

[grumpy one]

When a mold is colder and lead is just dropped in so you depend on the shrinking boolit to pull from the sprue, you will get all kinds of bad boolits. The sprue will start to set up before the boolit can draw in lead from it. Thats why most guys get better boolits when frosted because the sprue stays molten a little longer.


That is a good description of how I cast 311291 in my double cavity iron mould. If I don't cut the sprue until it's been solid a while, I get perfectly formed shiny bullets; if I cut the sprue as soon as it's solid I get a rounded rim on the base due to missing the last bit of filling as the contracting lead draws from the sprue. Either way I get all kinds of weight variation, and as Bass said, I may be getting voids as well, resulting in crooked bases after breech pressure is applied. If I get the mold really hot the frosty bullets fill better and have less weight variation. I find the double cavity iron moulds are considerably harder to heat up, and to keep hot, than a single cavity aluminium mould. Unless I either run the metal very hot or cast really fast, Bruce B style, I find I'm getting lack of base fill-out on one cavity or the other, even after I've been casting for a while.

[grumpy one]

Grump,

1. I understand. Figured that was where you were headed. Been down that path many times. Now I only do that extra stuff after I found what I want.

2. This is hard to interpret. Depends on so many things like what firearm and the conditions.

3. Uh huh. No difference from hardness? No difference from weight? Are you choking? If so, it is mandatory that you mold better bullets. Since most bullets are base pour, air is trapped in that area making them vulnerable to it. Longer bullets especially. Bullet deformation occurs as these are closed by pressure swagging and your base moves unpredictably out of square. That's why I also like light bullets per caliber, since weight effects are accumulative on the base and they are easier to mold well. No heavier than needed to reach the lands. Oooppps, that eliminates bore rides huh? :grin:


My results are that the more you try to shove in that little hole, the better your bullets need to be which may result in better average grouping over all, but the wilder your fliers will be.


4. Something to think about. Very few powders are going to take you from 3" at 50 yards, to 1/2". Pick one logical cast bullet powder for rifles like say 2400 to 4198 or equivalents. In other words, I can't go from 2400 to 5744 and expect a major difference. You may need a bold move. You may need a filler. (I hope not too many people read this) But I would stick to one powder until I isolated the problem and reached consistency. Then change powders.

You may be on the right track about your bullets if voids have been the problem for you.

2. I only own two centerfire rifles, both 30 caliber. The point applies to both of them. Group sizes for good loads (meaning loads that have ever been known to give close to MOA results) are approximately normally-distributed, with the lower extreme being 1 MOA, and the upper extreme being 3 MOA.

3. It seems to me the way I've been pouring may have been causing the weight variation, and the weight variation might be implicated in the group size variation. At the moment it looks as if really hot-cast, frosted bullets have very little weight variation, but I haven't yet tested whether the groups are more consistent.

My point was that the variability of group sizes doesn't seem to depend on whether I fire the whole group with hard alloy or soft alloy, provided I'm using a load that suits the hardness of the alloy I'm using. 44man's description of how an amateur goes about pouring shiny bullets applies to me, and it may be resulting in crooked bases after high pressure is applied, as you say.

4. I have found that some powders seem to give quite a bit more variability of group size than others. The main culprits seem to be W760 and Varget, in both the 30-06 and the 30-30. To my surprise I've found the variability even applies to maximum pressure J-bullet loads in the 30-06 - though the best loads under those conditions are MOA, whereas they are quite a bit worse than that at lower pressures.

[Bass Ackward]

I find the double cavity iron moulds are considerably harder to heat up, and to keep hot, than a single cavity aluminium mould. Unless I either run the metal very hot or cast really fast, Bruce B style, I find I'm getting lack of base fill-out on one cavity or the other, even after I've been casting for a while.

GO,

Ever wonder why one guy can .... and another can't? I do all the time. Sometimes it kills me. Like using LLA. :grin:

What I find is that when I need frosty bullets for fill out with a steel or iron mold, I really have a poorly vented mold when hot. Either my blocks have swelled with heat rising and tightening up the plate too much or the vent lines just close off at the top of the blocks.

I can tell if the plates are too tight because I start to see little bubbles in the sprue every once in a while that tells me all venting is occurring through the sprue. You should never see this if things are venting properly. I want lead flowing in continuously, not air out. All I am doing when I heat the mix that results in frosty bullets, is keeping the sprue soft enough, long enough to vent and then fill.

So I improve venting at the top with a nice stoned bevel on each block half to prevent those two problems. Helps to clean the vent lines with a scribe and I usually do this while I am waiting for the pot to heat up.

Doesn't take much, and then you can turn your heat back down and still get bullet fill out and ones that weigh properly and stay dimensionally correct.

And the best thing about shooting cast? It teaches you about shooting jacketed better.

[Petander]

I just got a sixbanger Lee, my first one.

It seems to easily keep a good, hot temperature for "silky" boolits, not shiny nor completely frosty. Everything looks very good and production is fast. Faster pace = frosty (hot) , slower pace = shiny ( cold) . Maybe neither of those is bad but I´ll probably keep only the silky ones. They also drop very well from the mold, another indicator to keep the pace steady. Still learning the mold, I made about 1000 boolits some hours ago and a couple of hundred yesterday.

I´ll measure and weigh them tomorrow to get more facts. Anyway, this is my first mold that obviously likes to make "silky" boolits. It simply works the best that way. I have one brass mold that likes totally frosty to fill, otherwise I cast shiny. Ooops, another aluminum mold likes "silky", too , a .500 LBT mold.


I like to try what works for a given mold, there´s not a short answer to this I think.

[LAH]

How you been Petander? Have heard from you in a while........Creeker