Using CB Bullets in your 10mm

Glen72 · February 05 2013 05:42:22 AM MST

Has anyone been reloading this type of projectile for there 10? I was going to try them but was thinking about the leading effect in the barrel.
Any corrective thoughts on this adventure?
Going broke and looking for alternatives, maybe making a carbide cleaner for the rifling to keep the barrel clean?

sqlbullet · February 05 2013 08:12:33 AM MST

Search is your friend:

http://10mm-firearms.com/reloading-10mm-ammo/who-shoots-lead/

Lots of us shoot lots of cast bullets in our 10mm's. 99% of what I shoot is lead.

Some comments on leading:

First thing you have to recognize is everything you have been told or read about lead bullets is wrong. And I can prove it. You have been told and have read that soft lead bullets will lead up your bore and be a pain to clean. They can't be driven very fast, usually 800 fps or slower.

Do you own a 22lr? Most of us do. And all we shoot through them is dead soft lead for the most part. Ever have issues with leading? Even with hi-velocity stuff moving 1200+ fps I have never had issues with leading in a 22. And most of the "copper jacketed" 22 LR out there has a jacket so thin you can cut it with a fingernail.

So, why don't we have these terrible issues with leading in the 22 LR? Simple...The bullet design is such that it will always fit the bore. They are almost always a soft lead, heal crimp, hollow-base bullet. The soft lead + hollow base means the base of the bullet will expand to seal the bore. And that means no leading 99% of the time.

Leading is almost always caused by bullets that are smaller than the groove diameter of the gun. This allows hot pressurized gas to vent around the bullet, superheating the sides of the bullet and the bore. The result is the lead melts and solders itself to the barrel of the gun. Hard bullets are worse than soft bullets because a soft bullet can obturate, or bump up a thousandth or two and fill the bore if it is undersized a little. A hard bullet won't do that.

So, first is fit. You must, and I mean MUST, drive an oversized soft lead slug, like a big fishing weight, through your barrel and measure it. Your bullets should be .001" larger in diameter than this measurement.

For my Para barrel and my new Schuemann barrel this is fine. They both measure .399", and most commercial cast bullets are .401". But for my Witnesses and my Glock I have a problem. The both measure .401", meaning I need .402" - .403" cast bullets. Try to find them, I dare you.

And this is the biggest reason folks get turned off by lead. They buy commercial, extremely hard lead bullets that are nominally .001" over spec for the caliber of their gun. But they don't ever actually measure their bore and find out it is already over nominal spec. The bullets lead horribly, so they tell all their friends that lead bullets don't work and are a pain and never to use them.

I would add this little bit of advice. After you slug your bore and track down (or cast) lead bullets of the correct size, and then load up some rounds, you need to pull a loaded round and measure the bullet. Many a reloader has been frustrated by leading despite carefully slugging the bore of their gun because their perfectly sized bullet was swaged down when it was seated and crimped. Early Lee Carbide Factory Crimp dies for 9mm and 40 S&W were especially guilty of doing this. The more recent ones have a less aggressive carbide ring and reports in general they work fine, but pull a bullet and measure to be sure.

Now, in 10mm dead soft lead WILL still lead your gun even if the bullet fits. This is because the operating pressure of 10mm Auto exceed the elastic deformation limits of pure lead. You bullet will strip in the rifling and you bullet base will be deformed, both of which will lead to poor accuracy even if they don't leave lead in your barrel.

In general I have found clip on wheel weight (COWW) lead (BHN of 10-12) to be the minimum hardness for most 10mm loads. I personally cast my own bullets from scrap isotope lead which is almost identical to COWW lead. I water quench the bullets from the mold which increases the hardness to about 22-24 BHN. They are harder than they need to be, but I never burn my hand by accidentally grabbing a hot bullet, and they don't get dinged up very easily. These bullets will fragment when they hit anything hard though, so they are not great for hunting or defense.

For hunting or defense I add 1% of tin to the mix and air-cool them. The resulting bullet will mushroom nicely but hang together even if it hits steel.

I have rambled on a bit, but encourage you to try cast bullets in your 10mm. But measure you bore and use a bullet .001" larger than you measured or you WILL have leading to deal with.

siberian505 · February 05 2013 08:20:31 AM MST

very good lesson on cast. my size die was a.401, now after some work it is .402. I do use a LWD barrel in my 20 mostly for better chamber support.

The_Shadow · February 05 2013 08:24:02 AM MST

Good write up sqlbullet! ${$default_cheesy_smiley}$

Mine are usually sized to 0.4015", lube also plays an important role in the procees of shooting them thru the bores.
Some lubes smoke more than others, probably because of poor bullet fit also.

sqlbullet · February 05 2013 08:35:13 AM MST

Shadow is right about lube. I make my own these days, but used lots of Lee Liquid Alox when I was starting. That lube is smokey, mostly because the base of the bullet gets lubed too I think, but it worked for me.

If I were still buying I would buy White Label Carnuba Red lube. If I were still tumble lubing I would buy their xlox as it is a bunch cheaper than the Lee lube. http://www.lsstuff.com/lsstuff-stuff

Glen72 · February 05 2013 06:14:04 PM MST

Your write up was so good i'm going start looking for some molds.
Are you saying i'm lazy? You are right! Never ever gave it a thought but, I wouldn't have been able learn from such a good write up.
Thanks!

Danimal · February 05 2013 07:02:52 PM MST

Don't have any experience with CB in .401, but I bought a couple K's of .430 a few years back and I was impressed with them.

I've since switched to missouri bullet co as they're local, and I'm too lazy to cast my own.

DM1906 · February 05 2013 11:32:37 PM MST

Quote from: Glen72 on February 05 2013 06:14:04 PM MST
Your write up was so good i'm going start looking for some molds.
Are you saying i'm lazy? You are right! Never ever gave it a thought but, I wouldn't have been able learn from such a good write up.
Thanks!

Don't worry about the molds, just yet. Get at least a couple hundred pounds of lead, and a steady future supply, first. Don't be picky, get what you can, as much as you can. It's not nearly as easy to come by as it once was. You can buy the rest of the equipment as you need it. Buying lead is cost-prohibitive. You're better off buying bullets. The greatest expense of reloading is the bullets. Cast your own, and the cost is 1/4 of before, or better. I reload for $1-3 per box, any of a dozen calibers, depending on the cartridge and performance level.

Glen72 · February 06 2013 05:06:30 AM MST

Again with some sound advice, I will be starting my collection.
I have as much fun reloading as I do shooting, to cold to work in the garage on projects.
Again thanks..

sqlbullet · February 06 2013 08:27:56 AM MST

If you like reloading, you will like casting. Same type of work, same "made it myself" satisfaction. And as DM1906 says, it is very cheap.

He is also right about the difficulty in getting lead. Used to be about any tire shop was glad to have someone come empty their WW bucket. Now, not so much.

I didn't start casting for many years because I didn't want to scrounge lead. I finally mentioned my desire to the right friend, a nuclear pharmacist, and now I have plenty. But finding a good lead source is definitely the key.

For molds, I suggest starting with Lee molds. They are very inexpensive and work OK. Once you have some casting under your belt, and can better determine what you really want, you can look to more expensive molds if you want. All of mine are Lee to this day, save one.