Casting Breakthrough with the 145-SWC. Effective on other moulds as well.

Smaller than expected bullet diameters of the 145 mould are affecting accuracy. Testing has shown that fullsized 360 bullets are best. 

The seam diameter ranges from .3591-.3594 in.  Across the seam typically ranges from .3584 to .3589. That is not good for achieving the best groups possible. 

First, the bottom line results.  The diameters now, after running a series of tests. measure .3598 to .3601 on the seam and .3593 to .3595 across the seam.  That's as dropped from the mould, before any aging grows or expands them.  (The effect of aging is the subject up an upcoming post.)

The final results are yet to be proven at the range, but that's coming soon.  So far the best groups have been 1.24 inches at 25 yards, with the undersized bullets.  From a rest of course, using my Red Dot Taurus 66, with a 6 inch barrel.

Lessons learned: Alloy temperature and mould temperature are absolutely critical. The alloy solution is easy, the Lee pot turned on full worked the best.  This is much hotter than most folks recommend, much.  Preheating the mould to 360 degrees also is critical.  The first cast will drop good bullets, then you must keep it from getting too hot.

First some data, then the process.  

The Lee pot is numbered 1 through 9, going all the way to what I'll call 9.5.  Casting at the different numbers, using the same one cavity and casting back to back, the diameters are in the chart. (click on it for a bigger view)

The numbers on the bottom are number of bullets cast in each test.  With more test bullets as the diameters increase.

The green line is the pot set to full hot, it's also is the one with the mould at 360 degrees.  This gives the maximum size, until the mould is too hot.  At that point size decreases, as you can see in the graph.

I ran a quick test and found that holding the mould on a wet rag for 5 seconds, than pausing for a couple of seconds, drops the temp 15-20 degrees.

Taking the lessons learned and putting together a test session produces the great results detailed above.  As a matter of fact a full casting session produced bullets even bigger.  All the way to .3601.  That's amazing.

The process that produces these fully sized bullets is repeatable and works on other moulds too.

The steps to follow are:

1. Get the alloy fully up to temperature before starting to cast.  Set to 9.5 then don't start casting until the pot cycles off.  This takes much more time than usual
2. Use a hotplate to get the mould to 360.  Use a basic kitchen thermometer with a flat bottom and stick it  into a middle cavity.
3. If needed, use the alloy in the pot to add heat to the mould if needed, dip the mould into the hot alloy.  Use a damp rag to cool it if it's too hot.
4. Start casting, (note: if one or two cavities vary in size, don't cast them.  Use the 3 or 4 most consistent and largest cavities. More on that in a future post as well.)
5. For the first third of the pot, every three casts cool the mould by pressing it onto the damp rag for a 5 count, remove it from the rag and wait another 2 count
6. Resume casting
7. The bullets look shiny when dropped and then show some marking as they cool.  Watch closely and you learn to tell from their "look" if the mould is too hot or too cool
8. After the first third pot it works best to cool the mould after 2 casts

That's it in a nutshell.  I suggest you do a similar set of tests and see how it works for you and your alloy.  Then refine the steps and the timing to work best for you.  

This test alloy is 98% lead and 2% solder, my preferred for all 357 magnum handgun bullets.

Next, the 145 bullets are aging for a week as part of another test.  The affects of the sizing/lube die, followed by the bullets enlarging will be documented in an upcoming post.  The range test is coming in the next few weeks.

Stay tuned and shoot well.

Update on 200 SWC, 145 SWC and also H110 Powder (most accurate loads update included)

The 360-200-SWC boolit has now proven itself with the best groups of any boolit so far.  With the ability to shoot between .5 and .6 inches from 25 yards it's incredibly accurate over 3.4 grains of 700X.  It's also a nice shooting light load.

The 360-145-SWC is hanging on the list with 1.2 inch groups.  This mould is a bit confounding.  However I've noticed that casting temperature and managing mould temperature is very critical.  I expect to post the results of alloy & mold temperature affects on boolit diameter, based on this mould.

The 200-SWC is a 2 cavity mould therefore casts boolits with a very consistent size.  The 358-429 is a outstaning 5 cavity, with 1-2 cavities that vary just a bit but has produced .6 inch groups.  The 145-SWC is dropping the smallest diameter boolits, at least most of the time.  When striving for the best accuracy, moulds with 2-3-4 cavities are more consistent and much easier to work with than moulds with 4, 5 or 6 cavities.  Casting with the 3 or 4 most consistent cavities promises to provide the tightest groups, more on that in the future.  The trade-off is throughput and how long it takes to cast 500 or 1,000 bullets. The best case is 4 or 5 cavities that cast equally.  When shooting groups less than 1 inch, and trying to break the .5 inch barrier, it requires extreme precision.

Magnum powders are now moving up the accuracy list.  The Lyman Cast Bullet Handbook got the load for the 358-429 right.  11.8 grains of H110 under the soft 6 BHN lead produced 1 inch groups with no hint of leading.

Below is an update to the top accurate loads.  The velocity isn't from a chronograph, but based on the recipes.

Rank	Mould	Weight	Group	Charge	OAL	Velocity
1	360-200-SWC	200	0.57	3.4, 700X	Groove	660
2	358-429	168	0.58	4.7, HP-38	1.620	900
2	358-429	168	0.58	5.1, 700X	1.620	1,200
3	158-SWC TL	158	0.61	3.5 HP-38	1.600	810
4	358-429	168	1.00	11.8, H110	1.620	1,260
5	158-SWC TL	158	1.10	5.1 HP-38	1.600	1,129
5	148-WC TL	148	1.10	3.5 HP-38	1.400	928
6	360-145-SWC	145	1.20	3.9 700X	Groove	1,020
7	358-429	168	1.30	10.3,2400	1.620	910
8	140-FN-LBT	140	1.40	5.8 700X	Groove	1,347

Update: 145 SWC Testing & 200 SWC Testing

I ran into a delay (besides the weather, which closed the range for days) due to a casting problem.  Based on early results I expected this boolit to be very accurate and group less than 1 inch.  As testing proceeded I could only get 1.2 inch groups.

Rather than blame the mould, I started reviewing the process, what may have changed and also started measuring the boolits more closely.  I discovered that for some reason they were slightly undersized.

The root cause: A new casting pot from Lee heats hotter than my old one.  This increase in alloy temp also heated the mould too much.  This is my fault for not double checking everything with a new bottom/pour furnace from Lee.

With alloy that was already hot, it heated the mould too much as well.  With the mould preheated on a hotplate, look at the graph of the boolit size as the mould is overheated (no frosting though).  As usual, click on the graph to see it full size:
 

The graphs shows the boolit diameter in sequence as 9 boolits were cast.  They start good and fall off as the heat builds.

Monitor the affect of alloy temperature and mould temperature on your diameters.  It has to be hot, but don't get to hot and end up with undersized boolits.  They just aren't as accurate.

The upside is that the only tests affected are the 145 SWC and early 200 SWC.  I have a great solution planned and once implemented and verified I’ll post it.  It's much more than just turning the pot down.  I want accuracy so it needs to be consistent.

Upcoming posts for additional accuracy tests:

• Results using H110 magnum powder will be coming in the next few weeks. 
• In the works is (already started for that matter) tracking the shrinkage of 357 boolits as they age.  When pursuing the best accuracy possible, it all makes a difference.  Especially for that event or day at the range when you want your “best of the best” loaded in the cylinder
• Oh, also coming is test results with a new-to-me Dan Wesson with a 6 inch and 2 inch barrel.  It has a different twist rate than the Taurus, more coming about that…  First I’ve gotta get all the lead out of the new revolver.  Enough has been removed to cast a 145 boolit, and there’s more!  My wonderful wife came to me on my birthday and said she’d like to buy me a gun.  Wow, I found the Dan Wesson and bought it.  After sitting at UPS for days due to icy roads it finally showed up at the Range/FFL.  It’s a Monson made model 15-2, what a nice trigger. 
• Ummm, there is that custom mould too.  Those results are a month or so out as the custom sizing die (for just $34) is needed as well.
• Did I mention my wonderful wife.  She puts up with all this and enjoy going to the range every so often too.  I really enjoy those range trips.

357 Magnum Accuracy Ladder, for Revolvers

Putting all the data gathered after a few thousand test boolits into a useful format is something I’m working on. First up is a list of diameters and alloys, starting with the most accurate. The bullets designs proven to be the most accurate all react to diameter and alloy changes very predictably.

357 Magnum Accuracy Ladder, base on results from tests at 25 yards off a rest.

Find the size and alloy hardness you are using and what will improve your boolit's accuracy.  Number 1 is the most accurate combination and number 6 has the biggest groups.  Other alloys and size combination's haven't proven to be nearly as accurate as this list:

1. 360 BHN 6 (pure lead with 1%-2% solder)
2. 359 BHN 6
3. 360 BHN 11 (WW or lead with antimony & tin)
4. 358 BHN 6
5. 359 BHN 11
6. 358 BHN 11

One point to clarify from earlier posts:  I referred to the alloy tested as 7-8 BHN, the Lee test kit doesn’t go lower than 8.  Then I was pointed to a very helpful chart that puts it at 6.2 BHN (thanks kelbro).  So all the other Blog posts are really talking about 6.2 as well, please make the adjustment when you read them.

While there is overlap that is not evident from the list, it still holds true at the range.

• That means there may be a few #2 groups that are better than a few #1 groups. 
• However the best #1 groups are always better than the best #2,
• and most of the #1 groups are better than most of the #2. 

Hope that makes sense.  Good shooting.

Quick and short update on the 145 SWC (full results to be posted soon)

A few folks contacted me and asked for any info that I may have for this mould.  They received their NOE moulds and want to get started.  So here is a quick update:

Assuming you read the rest of the blog and know that for highly accurate results soft and fat bullets (large anyway) work best.  The mould is dropping 99% lead with 1% tin at .3585 to .3595.  Pretty good as they are designed to drop WW at .360.  If possible go with an alloy as close to 98-99% lead with the rest some solder or tin.  If you all you have is WW, use that.  They both shoot some good groups, but the softer alloy produces slightly tighter groups off a rest, about 75% of the time. Softer is still more accurate.

The boolit seems sensitive to crimp, so a light to medium works.  If accuracy becomes a bit random you might be lose or tight.

Crimp in the groove and use either3.9 grains of 700X or 2.7 grains of 700X.  They are two very different loads and both standard pressure 38 Special loads.  4.0 would be the max for standard pressure. 

Let me know how this works out.  Hearing results off a rest or off-hand is always good.  Knowing a bit about your revolver is very helpful too.

I tested in a 357 using 357 brass, but these 38 special loads are the best so far.  I'll post more results to the blog as soon as I get final testing done

I'm also starting the same process with the 200-SWC so I'll post that too.

Note: I currently use a Lubrisizer with a .360 die.  Most of the time it doesn't do anything to the boolit except lube it.  If you pan-lube or tumble-lube try loading and shooting without sizing.  If they don't cause any problems like jamming the cylinder or making it rough to cock the hammer you are good  If they do then size to .360 and you'll be good.

Shooting Cast Bullets Over 1,000 FPS in a 357

Recently I've come across a lot of advice against shooting over 1,000FPS.  One even suggested that leading would quickly build and cause serious safety problems.  Another claimed that cast lead bullets melt at 1,200FPS.  Of course these claims are all false.  Two current Most Accurate Loads are rated (no chrono handy) at 1,120FPS and 1,200FPS.  Neither have leaded the barrel at all.

Another cast bullet myth is that loads over 1,000FPS require hard cast lead.  This is commonly accepted by many, if not most caster-handloaders.  The same two favorite loads are most accurate with very soft lead boolits. 7-8BHN, which is very soft.  In truth I can't measure the hardness of lead this soft as the Lee Hardness Tester starts at 8BHN.  The alloy is 10lbs of pure lead with 1 ounce of solder for tin, to help mould fillout while casting.  This is very soft, and it works very well over 1,000FPS.  Leaving a clean shiny barrel after 200 rounds or more in one session at the range.

With a good bullet design, like many SWC's, that fit the cylinder & throat, 1,300FPS and more, can and does work well.  That's with soft lead, not water dropped wheel weights or boolits hardened with any other method.

Some quick tips to shoot faster than 1,000FPS with lead:

1. Use a SWC from 158 to 200 grains
2. Avoid hard cast
3. Softer works better, BHN 8 is better than BHN 11-12
4. Bigger diameter is better, .359 is good, .360 is best (as long as your gun will chamber it)
5. Swaged or undersized bullets may work just fine, but may need a coat of Lee Liquid Alox to help lube them

The most accurate bullets bullets work the best at all velocities, especially over 1,000FPS.  Look at the info at 357 Magnum Accuracy is About Semi-Wadcutters

Check out the other posts about alloys and accuracy in a 357 magnum.  Note I can't stress enough that the softer lead is more accurate more often than harder alloys.  While it's very possible to get good groups with WW and even water dropped WW.  They do have more flyers.  The soft boolits will out-shoot the harder 7-8 times out of 10.

So don't worry about the 1,000FPS being a limit for your plain base boolits.  Bevel base can work, HBWC's are another matter, light loads only.

Off topic and just for fun, here is a picture of what promises to be a great 357 revolver.  Dan Wesson of CZ USA is releasing a new 715 this year.  Is that sweet or what!

The Most Accurate Boolits and Loads for 2010 (a best of .6 Inches at 25 Yards)

All testing was done in a Taurus 66SS6 for 2010.  That's a 6 inch 357 magnum revolver with at 16.5 inch twist rate.  The objective is to find the most accurate boolit (cast bullet) handload's at 25 yards.  Why?  Because it's fun to shoot great groups.  Using a rest is a way to remove the shooter from the equation and to better evaluate the boolits/load/gun performance.  A superbly accurate handload does translate to great  off-hand groups too.  It just takes range time and a lot of casting, handloading and shooting, which is the most fun of all when pursuing accuracy.

It's worth a reminder, there are plenty of boolits that are accurate up to 15 yards.  When moving out to the range maximum of 25, most of them didn't even group at all.  While groups (center to center) of 2 inches or less are good, I'm looking for 1.5 inches to make the list and better than 1 inch to keep the mould.

It helps with cash flow to sell moulds to buy more to test.  It's a money losing proposition, but it is a lot of fun.  And that's what this is really about.  Casting, handloading and shooting for fun.

I'm currently testing a 358-145-SWC that looks very promising.  However accuracy testing isn't complete yet.  I'll add more on that in the future.

The most accurate alloy in all testing continues to be very soft 7-8BHN.  I use pure lead with 1 to 2 oz of solder.  If anything, the alloy is softer and not any harder.  The most accurate size is 360.  There are actually 6 loads listed as there is a dead tie

1. 358-429, 168 grain Keith. OAL of 1.620 loaded over 5.1 grains of 700X or 4.9 grains of HP-38. Both loads have a best group of .6 inch with the 700X being more consistent. My mould is from NOE and is a joy to cast with.
2. 358-158-SWC TL, from Lee. OAL of 1.60 loaded over 3.5 grains of HP-38. This is a great deal and is a tumble lube design from Lee. Crimping into the second groove works best in the Taurus. This mould can produce a bunch of boolits fast, assuming a 6-cavity is used. The best groups are slightly bigger but still less than 1 inch.
3. The same 358-158-SWC TL from Lee over 5.1 grains of HP-38 groups just a bit bigger, but not much.
4. The 358-148-WC TL from Lee also grouped at 1 inch. OAL of 1.40 over 3.5 grains of HP-38 is an awesome wadcutter load and can group right at 1 to 1.25 inches on a good day.
5. 358-429, the 168 grain Keith, OAL at 1.620 loaded over 10.3 grains of 2400 can group at less than 1.5 inches.  It is the first magnum powder tested to be this accurate. It isn't a high-power load, but is the best grouping with this powder.
6. 140-FN-LBT, from Lead Bullet Technologies. Crimped into the groove and loaded over 5.8 grains of 700X grouped just under 1.5 inches. This is a near max load and the most accurate for this mould.

That is the top list for 2010.  These exact recipes may not be the best in your 357 revolver, however they should get you close.  It takes a bunch of patience and testing to fully develop the most accurate handloads for your 357 magnum, it's worth the effort.  I hope this can help you get there a little more quickly.  Just saving time and not wasting it on trying to alloy and pressure match should be a big help (see previous posts listed on the right).

In 2011 the refinement and testing will continue.  There are more moulds on the way and maybe a surprise or two in the works as well.  This Most Accurate list will evolve over time.  Let me add, the early 358-145-SWC results will upset this list once testing is completed.

Just for the record.  I'm not out to prove some theory is right or the best, or to disprove practices such as "alloy and pressure matching for accuracy".  I cast, load, test, measure, record results and then do it over and over.  The analysis of the results takes a lot of time.  I'm always force ranking the best results to the top of the list.  In the end the results speak for themselves.  If a "commonly accepted" practice doesn't work, I'll say so.  If it does work, I'll also say so.

Gotta prep for more casting in the morning so time is short.  These 145-SWC's are working out very well.  Stay tuned for more info.  Shoot well and be safe.

Additional Comments on Alloy & Pressure Matching for Accuracy, the Myth

Details and background can be found in this prior post. 

I noticed some interesting data from my test records: All data is from testing with my 357 magnum, a Taurus 66, 6inch:

With a 358-429 168 Keith bullet: the most accurate loads & alloy:

700X at 28-30,000 PSI wiht BHN 7-8
HP38 at 18-20,000 PSI with BHN 7-8

These two loads are capable of groups less than 1 inch at 25 yards, from a rest.  The reason I favor 700X is the consistency of the tight groups.  It's just a bit better.

With the same cast boolit, the most accurate load with the 2 different powders is with different pressure levels.  It turns out the most accurate alloy was the same for both pressures.  That makes the comparison very relevant to disproving alloy and pressure matching for accuracy.

The most accurate load for a 158 SWC is:

HP-38 at 24-25,000 PSI with BHN 7-8

This is another pressure level for the same alloy and is the most accurate load I've found for a Lee 158 SWC TL cast boolit.

Looks to me that the most accurate loads depend on "boolit design & weight" matched to the powder.  The pressure ranges from 18,000PSI to 30,000PSI for the same alloy.  This pressure range is not even close to the 10,370PSI the formula from Lee provides.

When pursuing the best accuracy, the calculations don't work in a 357 revolver.  Different pressure levels have proven to be the most accurate with the same alloy, when using the most accurate powders.  Maybe I'll have to refine that claim, however magnum/slower powders just don't beat or even equal 700X and HP-38 for accuracy.

Pressure and Alloy Matching for Accuracy. Fact or Fiction in a handgun?

The engineering on this topic is fun to read about and for discussion. There are BHN charts, lead deformation charts, calculations to provide obturation pressure, accurate-pressure and a way to determine the maximum pressure for cast boolits. However taking it to the range and validating something like "matching pressure to BHN for accuracy" to me reveals the truth of this widely accepted and commonly promoted & quoted “claim”.

The reason I even bring it up is there are plenty of articles and books about this that get read and then recited as fact.   Many people are trying to figure out what’s wrong with their gun because of their bad results at the range.  This concept is often promoted by pundits and then is passed along as fact in various online forums by folks that have assumed it's valid.


But is it?

First, the Context

My goal is the best accuracy possible and all my comments should be read with that in mind.  What I’m about to cover may not/will not apply to someone who has decided they need a max charge of H110 with their 158 or 168 boolit and want to then make it a bit more accurate, keeping it at the max charge.   


I have yet to get the best accuracy with full house loads therefore don’t work with them much, but hope to in the future.  But using a download charge of 10.3 grains of 2400 (168 Keith) is not bad with 1.2 inch groups at 25 yards very possible.  It’s a far cry from a max charge though and was derived by searching for the most accurate 2400 load, not trying to achieve maximum velocity.  


I hope that made the point and helps clarify the goal of this blog. 


What is Pressure and Alloy Matching for Accuracy?

Finding information that describes the approach is pretty easy.  Modern Reloading by Richard Lee is one of the better known sources so I’ll briefly give his formula.  Note that he tested with rifles and not handguns, just like many other proponents.  Richard Lee never claimed this works in handguns, as far as I know so this isn't a slam against him or the book.  From that, many others have assumed it applies to handguns too, they are the ones that promote this as fact:


BHN*1422*.9=Accurate-pressure for cast bullets, called Max pressure in the Lee book, another key formula is:
BHN*1422=Alloy-strength and part of the information distributed by Lee, also;

BHN*1920=Maximum-pressure for cast bullets (this isn't based on the Lee book and is much higher than the Lee alloy strength formula)


Based in these, the accurate-pressure for my BHN 8 alloy is 10,370PSI, the alloy-strength is 11,520PSI and the maximum pressure is 15,360PSI.  Using the same formula for accuracy the best BHN for a 30,000PSI load is roughly BHN 24.


Compare these numbers to the results. 


Testing in a 357 Magnum for Accuracy, Results 


After testing several thousand boolits of different hardness, different diameters, different OAL, with and without gas checks I have proven beyond any shadow of a doubt that, first, one of the most accurate loads with a 358-429, 168 Keith in my 357 magnum is:

A 700X 30,000 PSI  load is most accurate with BHN 7-8 (< 1inch groups using 700X) 


This is 3 times the ideal matched pressure/alloy and is 2 times the maximum pressure.  The results are starting to prove that pressure matching is a hoax, at least in a 357 Magnum revolver.


Now the question is, does lower or higher pressure perform best with correspondingly lower and higher  BHN?  If not, pressure matching isn't for real and is disproved,

The most accurate BHN with other pressures and using HP-38 (slightly bigger groups by .25 to .5 inch bigger at 25 yards, still <1.5inch which is very good) are:

A HP-38 10,000 PSI load is most accurate with BHN 7-8
A HP-38 20,000 PSI load is most accurate with BHN 7-8 (this equals 700X, but isn't as consistent)
A HP-34,000 PSI load is most accurate with BHN 7-8

Any increase in BHN opens the groups and is less accurate for each of these loads. The harder the alloy the bigger the group.  The same BHN at all pressures is the most accurate with the same or similar powders.  That's worth talking about in another post as it turns out to be important.

 

Matching or increasing the alloy BHN with the pressure caused bigger groups.  Accuracy suffered!

I’ve tested a bunch and let me say this isn’t my entire database.  But it is one striking example that I trust makes the point. 


The Conclusion

This completely disproves Pressure and Alloy Matching for Accuracy, in a 357 Magnum Revolver.  It isn’t even helpful when trying to achieve better accuracy.   

Added: I've been told that once an accurate load is worked up, the alloy and pressure is matched.  This interpretation of pressure and alloy matching is limited and mistaken in this context. That's simply the most accurate charge for a given power with that bullet.  

To test this, change to a different powder (especially one faster or slower) and work up the load.  There's a good chance it is most accurate at a different pressure.  

Which pressure is correct for that alloy, according to the formula there is only one, but in practice it changes with the powder used.

Alloy and pressure matching does use peak pressure as the measurement.  That's what is being addressed here.  If someone tries to complicate the issue by pointing out the pressure curves change with a powder change, knowing that fact doesn't make the pressure-alloy matching valid or predictable. It means the most accurate load is at different peak pressures for different powders.  The most accurate powder is most often at a pressure very different than derived by alloy-matching.

It also means the most accurate load for a given powder must be worked up the old fashion way.  By shooting and measuring groups at the range.  Not by using pressure and alloy matching formulas.

Does matching work in other handguns?  I’d be speculating as I haven’t proven it doesn’t.  It wouldn’t be outrageous to assume another revolver or even a semi-auto would be more like my 357 Magnum than a rifle though.

I'm not claiming that BHN 7-8 is the most accurate alloy in every gun, there are many other factors are at play.  My test results indicate that bullet design and how it fits in the throat/barrel grooves is more important.  Powder choice is critical and tied in importance with fit, as it can and will limit just how tight the groups are (past 15 yards).   Followed by alloy and last of all, diameter (that relationship is important to understand, more coming in a future post).

With the right bullet, like the 358429 Keith loaded at 1.620, any diameter bullet shoots at any pressure without leading (in my Taurus 66 at least).

Though fatter boolits give smaller groups at the 25 yards (my test standard as that's how long the range is).  This is not common knowledge or commonly accepted.  However I’ll post more on other myths soon. 

CLOSING POINTS

After several thousand boolits of testing across alloys, moulds, OAL, crimp, etc... the results are in as far as I'm concerned. At one time I tried to achieve accuracy using pressure & alloy matching.  I accepted this "matching connection w/pressure" concept as valid, it caused me to spend many hours and many boolits trying to figure out what was wrong with my boolits, my gun, or my casting approach. In hindsight it was a good learning experience. But I wish someone just let me know up front...

Those that write about this concept, those that I've read, have extensively tested with rifles ONLY.  I'll try it again if I ever get interested in rifles.  But for my revolver, and probably handguns in general, working up loads based in starting recipes and testing the other variables (including loads) is time much better spent. Alloy/Pressure Matching for Accuracy is fiction in this case.  If you cast for a handgun, it's most likely fiction for you too.

The last word: Pressure isn't an important part of the equation when loading for accuracy.  Knowing what the PSI or CUP is really doesn't matter.  You and I already know that 5 grains of HP-38 is higher pressure than 3 grains of HP-38.  Beyond that, it doesn't matter what it is, as long as it's safe for gun.

Taurus 66SS6 (357 Magnum, 6 inch barrel) and Tasco Red Dot

This gun is the most fun to to shoot tuned cast and handloaded ammo in.  Great feel, doesn't break the bank and very accurate.  With older eyes the Red Dot works out great.  Glasses that are needed to focus on iron sights make them tough to shoot at 15 and 25 yards.  The targets are just to blurry.  The Red Dot doesn't magnify at all and is large enough so both eyes can look through it, focus on the target and still see the dot.


For accuracy testing my rest is an old rolled up rug with tape holding it together.  It moves a bunch and isn't the best but it inexpensive and seems to work well enough.  To help compensate for my error I shoot 4 groups of 5 rounds each when testing at the range.  I measure the groups and record them, always force ranking the best to the top of the list.

My Taurus with some test results from earlier in 2010:

168 Keith Boolit, an Excellent Design

I've spent a lot of time buying, casting, loading, testing, and then selling moulds.  The design that keeps rising to the top as consistently accurate is the Keith.  For instance the 168 or a SWC which is fashioned much like a Keith. Everything else gets sold off unless it can group less than 1 inch at 25 yards.

The best so far is a 168 Keith cast from a Night Owl Enterprises (NOE) mould.  I really like it, as it has the plain base, squared off large grease groove and 3 equal size driving bands.  I suspect the crimp groove is modified a bit from the original design of Elmer Keith, but it works well and that's what I care about.  Most important is the 1 inch or less groups that it is capable of. Off a rolled up carpet rest.  That's pretty good in my book.  The best group is .6 inch measured center to center.  I judge the mould, the design and the final boolit by how well they perform and this is excellent performance.

I grabbed a few that I cast this morning and took this picture:

There's at least one that's rounded and will be recycled, but this should give you a good idea of how they look.  As a footnote: these are 10 lbs of pure lead with 1 oz of solder for tin.  This is consistently the most accurate alloy in my 357 revolver.

A 145 SWC from NOE just showed up so sometime in the next month or two I'll post those test results.

The Lee 158 SWC TL is also an incredibly accurate design when loaded in 357 brass and crimped into the second TL groove.  Lee Alox works well as a lube, but I prefer the shiny barrel left by a conventional homemade lube such as Darr lube. Since I force rank the boolits, even this mould got sold off to help fund testing another.

Right behind the 168 Keith and the 158 SWC from Lee is the 148 TL Wadcutter from Lee.  It's very accuracte, however it groups slightly bigger.  So it got sold too.

The various other boolits like the 105 SWC, the 158 RF (flat nose) and several other flat nose designs didn't group well at 25 yards.  So they all got sold too.  Some are from high end mould makers and are costly.  If they don't group less than 1 inch, they are sold.

I'm looking for the best accuracy in my Taurus 66, 6 inch revolver and can't imagine starting a casting session excited about using the second best or third best mould.  It takes some time to cast, lube and handload so why not use the best most accurate boolit all the time  I'm sure I'll find something I really like and may end up with 2 or 3 keepers.  But they will have to have something very special about them, or they will all get sold.

The NOE 168 Keith is very special, it's a keeper.  I'm looking forward to casting and testing the 145 and begin evaluating it.

Find the most accurate design that works with a good throat fit and everything else works better.  Once you get something capable of less than 1 inch, work with it, practice with it and enjoy the results.  Even shooting off-hand the groups are excellent, that's actually how most of my 1,000 rounds a month are shot.

More Accuracy Tests, Keith 168 Bullet with 700X Powder

I did some testing for accuracy today and thought I post the picture of the best group of the day.

This is with the same 358-429 Keith bullet previously mentioned in the 357 mag post.  They were cast yesterday and test at 7-8 BHN today.  OAL is 1.620, lubed with Darr and 360 diameter.  On paper the velocity is 1,200 FPS.  It shot great, felt great and no signs of leading.  Although more rounds are needed to verify the clean shiny barrel is for real.

700X with this bullet produced a .6 inch 5 shot group measured center to center.  This 5.1 grain load equaled the best HP38 load so far.  That's early results with very limited testing.  I'm looking forward to shooting more of this load.  Hope the lead doesn't get much harder with age as the groups get bigger when it does.

This is good as 700X is one of my favorites, it can be extremely accurate.  It's a flake powder that meters well in my Dillon powder drop.  It worked well with Lee auto-disks before I switched to a Dillon Square Deal B.  Some folks report feeding problems, but if you want a great fast powder that's bulky, give it a try and see how it works for you.

Results from extensive testing, in pursuit of accuracy.

Working on accuracy in my 357 magnum Taurus 66, 6 inch barrel is great fun and an excellent hobby.  My goal is to obtain the best accuracy possible with cast bullets, or boolits in some circles.  Let's get started.

Accuracy can be achieved in all the moulds tested at a distance of 15 yards and less.  The big news to me is that some bullets that are accurate at 15 yards completely lose it at 25 yards.  On the other hand, everything that is accurate at 25 is extremely accurate at 15, that I did expect.

The loads and bullets listed are all capable of 1.5 inch groups or less at 25 yards.  Everything else didn’t group at all and won’t be the focus of this update.

The most accurate rounds to date are all using 357 brass as the length is critical.  The alloy for each bullet on the most-accurate list is 98% lead and 2% tin (more about alloys later):

1 - 358-429 Keith from NOE Moulds, .360 diameter at 168 grains over 4.9 grains of HP-38 and OAL of 1.620.  Groups of 1 inch or less are possible with this combination, with a best of .6 inch.  This bullet is big and may not fit in all revolvers.  It almost sticks out of the cylinder.  This is barely a +P load and was pan lubed with Darr lube.  Lyman lists 4.6 grains as the max standard pressure charge for 38 Special.

2 - 358-158-SWC tumble lube from Lee, unsized (roughly .3595) at 158 grains over 3.5 grains of HP-38 and OAL of 1.60.  Groups of 1 inch are possible with a best of .7 inch.  This is crimped into the second groove to get some length and is a 38 Special load.

3 - 358-158-SWC tumble lube from Lee (same as above), this time over 5.1 grains of HP-38 and the same 1.60 OAL.  Groups from 1 to 1.5 inches are possible with this light 357 load.

3 – 358-148 WC tumble lube from Lee, unsized (around .3595) at 148 grains over 3.5 grains of HP-38 and OAL of 1.40.  This is a tie for third best with groups from 1 to 1.5 inches and is a 38 special load.

Key factors to achieving tight groups, in the order of importance, at least in my view, are:

1 – Bullet design with good throat fit and the correct OAL.  Best accuracy is achieved with designs that help to center and align the boolit with the barrel, sometimes this requires a long OAL.  Not all revolvers will work well with these exact OAL’s, however keeping the bullet nose approx .03 inch from the front of the cylinder can sometimes help.  The Keith is actually .01 inch from the face, not much, and it’s accurate.

2 – Next in importance is the alloy.  This list is short.  The most accurate is BHN 7-8, a little bigger grouping with BHN 11-12, and even bigger grouping with BHN of 16 and greater.

3 – Last in the critical tuning controls is diameter.  Another short list, the most accurate is .360 followed by .359 and then .358.

Powder is key and HP-38 works well with lead.  I expect other powders may work as well but haven’t verified or tested very many.  I'll also be testing more with 700X which is another proven favorite.

Added later:  Crimp is also important.  A good medium to firm crimp results in the best groups.  It's also very important that bullets don't pull out a bit and lengthen as as may prevent the cylinder from advancing. You will need to experiment with this to see how it works with you die set.  Too lose and the bullets pull and groups are bad, too tight and groups are bad, just right and the groups get tighter.

I wanted to highlight what worked the best and won’t go into the thousands of bullets that didn’t work quite so well.  Accuracy with Magnum powder testing is ongoing and the results aren’t all that impressive so far.  Gas check didn’t improve or even duplicate the best results, so these are all plain base cast bullets.

The bottom line: soft and fat bullets loaded to fit the throat (sometimes long) over lighter loads are very accurate.  Bullet designs that don’t fit the throat well just aren’t as accurate as those that do.

Sorry to go so long, I tried to keep it short… ttyl

P.S.  Best accuracy for TL bullets is with LLA (used on all TL test bullets) with 2 medium coats followed with motor mica.  This is different than the light coating, or mixing the LLA with mineral spirits or Johnson Paste Wax that others seem to have good results with.

P.P.S.  Sizing to throat size and/or .001 to .002 over groove are not very accurate in my revolver.  These suggested sizings can be found in various places and didn't work.  Water dropping them didn't work either.  My revolver's throats slug at .358 and it has a .357 groove.

P.P.P.S. My rest is a rolled up carpet (taken when my wife wasn't looking) with some tape around each end.  Achieving decent groups off-hand will take many more thousands of boolits.

Multi-forum Poll: Most Popular Powder for Handguns

Below is a chart of the poll results. On several different forums I asked the same question.  Each person could vote for up to 3 favorite powders.  A total of 1,571 votes from 555 voters make up the chart.  It's interesting data, it did change which powders I plan to test next in my 6 inch 357 magnum revolver.


The question posed on each forum:

Please select up to 3 powders that you use the most when loading for handguns

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The selections are heavily influenced by what I load. Sorry if your favorite is missing from the list.

By favorite, I mean the one you use the most of. You buy it more often than the others. If you really love a powder but don't buy it because it fills a niche you can vote for it if you'd like.

The reason I suggest 3 votes per person is to allow for a fast, medium and slow powder. However vote as you see fit.

Again, this is for handguns. You should be able to change your votes if you think it through and change your mind.


Click on the graph to make it larger: