Consistent bullets for accuracy?

[Wilson]

After casting 7,000 bullets last weekend I feel like I’ve got the basics pretty well down. My loads are working very well for their intended purpose, that is supplying my wife and myself and seven kids (only 3 are my own) with ammo to practice and shoot Steel Challenge and Practical Pistol matches.
I’d now like to know what we can do to build a more consistently accurate cast bullet? At last Wednesday night’s shoot the bull’s-eye was 4” in diameter at 15 yards.
My alloy is straight wheel weights, I’m using a Lee 20# bottom pour pot set at around 850 degrees, a Lyman mold 147 grain 4 capacity (part # 2670637) for 9mm and a Lee 6 cavity mold, 125 gr # 356-125-2R for .38. I’ve slugged my 9mm barrels and found them to be .354 and .355. I size my 9mm .356 and my S&W Model 19 revolver .357. I water drop all bullets.
What are the little things to consider when trying to cast a very consistent bullet for accuracy?

[Bret4207]

My Smith 38 and 357 all get .359 boolits. You can try non-water quenched, different seating depths, different loads, primers, etc. If your boolits are coming out visually good -the bases especially, and a group of 25 are all within reasonable weights, then the rest is finding the best load for each gun. No one load will usually found to be "best" in all guns. You have to play around a bit, find an acceptable, for you, level of performance and decide when to call it good. If nothing you shoot demands better than 4" at 15 yards ... only you can decide what YOUR criteria are. Each individual gun is a law unto itself when looking for THE LOAD.

[CJR]

Wilson,

For revolvers, it's more important to size the bullets to fit the throats of the cylinder than to size the bullets to fit the barrel. Ideally, the bullet diameter should be 0.0005 inch less than the cylinder throat diameter.

Likewise, many bullet shapes, both cast and jacketed, do not have form stability, i.e. after leaving the barrel the bullet starts jawing and the bullets flys a cork-screw path where its diameter opens up as range increases. This was documented by Dr. Mann and his book,"Flight of the Bullet". On form stable bullet shapes, the jawing motion gets damped out, aerodynamically, and the bullet flys a smaller diameter cork-screw path and is more accurate.

Finally, many current handloading guides indicate the most accurate load based only on the variation of the measured muzzle velocity and not groups fired on paper. Result? You can have very uniform muzzle velocity, with low standard deviation, but lousey groups on paper if the bullet shape is not form stable. This inconsistency has been well documented by many respected researchers; Ken Waters, etc. There have been many cast bullet designs, brought out in the past, that proved over time to be very inaccurate and they were then dropped by the manufacturer.

The best advice seems to be to buy the bullet design that has proven over time to be the most accurate, and then for revolvers to size the bullets to fit the cylinder throats to within 0.0005 inch. Sometimes it also helps to reduce the diameter of the resizing button in the resizing die so that the bullet is held tighter. This promotes better powder burning and hence better accuracy.

Hope this helps.

Best regards,

CJR

[44man]

The way your boolits are cast usually won't effect things much as long as they look good and the bases are good. Since you shoot very close ranges, you could even have some bad looking boolits mixed in there without a problem.
The first question to ask is to your gun! Does it like the boolit?
After working with alloys and hardness, diameters, loads and all kinds of powders and the boolit still will not shoot, it is time to take a critical look at the boolit design and weight.
I have a few for my guns that just won't shoot no matter what so the molds stay in the drawer. One thing I never will understand is when I have two boolits that look almost the same and weigh the same but one shoots like crap and the other is a one holer.
A boolit that my guns like can be accurate with a variety of powders with a little workup. With a good boolit I have even changed alloys and hardness all over the place and it will still shoot. POI might change but groups will still be tight.

[HeavyMetal]

Looks like your getting some sound advice already! I'm also glad to hear your getting the casting thing down pat.

I will suggest you find Ken Waters 9 mm Luger Pet loads update in the May 1982 issue of handloader Mag.

This article has been an eye opener for me and has been my standard reference for the 9 since the day I first read it!

Ken "discovered" some intersting information concerning the 9 mm case's. When you get the article please pay close attention to that section of his article as it is really the "heart" of making a 9 shoot!

If you can't find a copy or a copy of pet loads PM me your addy and I'll mail a copy to you!

As for the .357, good advise about matching boolit to cylinder throat has already been given and I will second it! The choice of the Lyman boolit was probabely made based on the "best shape" for a reload concept. Good Idea! However I think some time on a sand bag and playing with diameter of the boolit is called for before you continue using it!

I think playing with case's in the 9 and boolit size in your 357 will net you what your looking for. I'd make the time to do the needed research before I'd play with different powders.

Change one thing at a time and then test it is the best advice I can give you!

[Boomer Mikey]

44man's advice is excellent for your application... keep trying different bullet designs to find the one your gun likes.

Bullets must seat in cases without shaving lead and there should be enough bullet pull tension that a primer alone can't pull the bullet from the case.

Lots of times a specific bullet is excellent in many guns of the same type for the same application but slight variations in molds from the same manufacturer will make or break a bullet's accuracy potential... the Keith designs are a good example of how excellent designs became average by design changes for the purpose of easier manufacturing. Some times it's just a bad run of molds.

Try to get some bullets or borrow molds from friends that shoot the same discipline well and network with them to find out what generally works best. Most of the guys and gals are happy to help.


Boomer :Fire:

[Wilson]

How do you check the size of the throats of the cylinder? Do you slug each one like you do the barrel?
What are the best bullet designs that have been proven over time to be the most accurate for the .38 Special? …the 9mm?
What do you use to measure 0.0005 inch?

[CJR]

Wilson,

You can use soft fishing weights to slug the cylinder throats. A micrometer would then be used to "mike" the slug's diameter. For 38 revolvers the Keith bullet is pretty accurate. For 9 mm, the flat nose truncated bullet is also very accurate. The 9mm truncated bullet design was developed by the Air Force, with help from Smith & Wesson and Hornady, and then extensively fired for accuracy. The Air Force scientists then scaled up the 9mm to 45 ACP which is also accurate.

Hope this helps.

Best regards,

CJR

[Bret4207]

Well, first off you don't need to worry about sizing to .0005. That's 5 ten thousandths or half a thousandth. There isn't a sizing die made that'll guarantee sizing within a half a thousandth. My best advice would be to size as large as your cylinder throats will handle, within reason. If your barrel is .358 and your cylinder throats are .359 then size to .359. If you have a freak where the cylinder is .005 over barrel size then split the difference and size .002-.003 over barrel size at maximum. Yes, you slug each cylinder thraot like you do a barrel, or use pin gauges.

The most accurate design? For the 38/357 up to 25 yards a wad cutter works well. Over 25 yards aerodynamics play havoc with the WC and a more streamlined design works better. The plain old round nose 358311 works and do the SWC and TC designs. It depends what your gun likes. This is where CJR's stability comes into play. Depending on your barrel, load, alloy, temperature, humidity, wind, elevation, and a bunch of other things each gun will decide what it likes best. Some guys have guns that shoot great all year with a certain load, others have summer loads, winter loads, loads for the snubby, loads for the long barreled gun. It depends on the shooter and gun. Only you can decide when you've reached the stopping point.

Some good designs for the 38/357 are the Lyman 358311, 358477, 358156GC, 358429. RCBS, SAECO, Lee, NEI and the custom makers all make good designs. There are reams of published info on accurate shooting loads and how to find them from Dr. Franklin Manns "The Bullets Flight, from Powder to Target" written around the turn of the 20th century to the latest information found today on the web. I'd look at the recent loading manuals and information found in places like this board. Keep reading and researching and you'll come to your own conclusions and that's what will lead you in the right direction.

[runfiverun]

pick one gun. fix how it shoots then move on to the next one.
if generic worked, we all would be buying commercial and shooting more and casting none.
i have 3 9mm's and 3 boxes of 9mm brass.
two will shoot the same load,but like different hardness boolits.... and i am still working on the third one.

[dardascastbullets]

After casting 7,000 bullets last weekend I feel like I’ve got the basics pretty well down. My loads are working very well for their intended purpose, that is supplying my wife and myself and seven kids (only 3 are my own) with ammo to practice and shoot Steel Challenge and Practical Pistol matches.
I’d now like to know what we can do to build a more consistently accurate cast bullet? At last Wednesday night’s shoot the bull’s-eye was 4” in diameter at 15 yards.
My alloy is straight wheel weights, I’m using a Lee 20# bottom pour pot set at around 850 degrees, a Lyman mold 147 grain 4 capacity (part # 2670637) for 9mm and a Lee 6 cavity mold, 125 gr # 356-125-2R for .38. I’ve slugged my 9mm barrels and found them to be .354 and .355. I size my 9mm .356 and my S&W Model 19 revolver .357. I water drop all bullets.
What are the little things to consider when trying to cast a very consistent bullet for accuracy?

Hi Wilson,

To cast high quality match winning bullets requires a great alloy devoid of impurities, a consistent casting speed, and consistent mould temperature. Along with those attributes, the sprues must be on center, the bases and all fillets must be without flaws, and the sprue must be cut clean without gouging. All of these points if met will produce very high quality cast bullets that will have very little variance in weight distribution. Walla, a match winning cast bullet!

I trust that this information will help you.

Matt

[Wilson]

Thanks too all. I'll try and apply some of the above suggestions soon.
Best Regards,
Bill Hickman