Reducing 9mm leading?

[Deus Machina]

Been getting some stubborn leading in the barrel of my CZ PCR.

The recipe I use is 2.9 or 3.1 gr Red Dot, behind a 125gr LRN cast from wheel weights in a Lee mold, and just recently changed to a 124gr tumble-lube mold.

Lubed with Lee liquid alox, dried, and tossed with just a little corn starch to keep from gumming up my dies.

Leading has been mostly further down the barrel, and while I haven't noticed any difference between the 125gr non-TL and the 124gr TL cast bullets yet, but I have been shooting the two together in the same session.

 

[zxcvbob]

Have you tried using talcum powder instead of cornstarch?

That's a pretty light load. I load 9mm much hotter than that (IIRC, I loaded Red Dot a lot closer to 4 grains with 124's but I don't remember the exact amount) and I don't get much leading at all -- I wonder if you're too low? I'm using commercial cast bullets. Will start using my own bullets once I get these all used up.

 

[LiveLife]

I use Promo with Red Dot data to load Missouri Bullets 125 gr 9mm bullets (0.356") using 3.8-4.3 gr at 1.125" OAL. I get minimal leading in Lone Wolf barrels / Glocks.

As zxcvbob posted, bump up your charge and see if the leading decreases.

I have never heard of corn starch/talcum powder being used with bullet lube - maybe some others who cast bullets can comment.

 

[Randy1911]

Usaually when you get leading farther down the barrel it is a sign of running out of lube on the bullet. Try some wax lube bullets with the same load and see what you get. I load a 124 gr. LRN wax lube bullet with no leading at all.

 

[Deus Machina]

The leading isn't overly bad, but it's stubborn and streaking, not like the light coat of vaporized lead from the base burning.

The corn starch is to keep the alox, which covers the bullet's nose, from building up in the dies.

I'll try talcum and see if it changes. Otherwise, is it perhaps from the increased time in barrel, from the light load? I'll try tacking it up to 3.3 or 3.5 (My Lee manual says max is 3.1, but lists a low pressure) and checking.

I'll also try more of the TL-style bullets, and see if they indeed do have a noticable difference from the non-TL style. And grab some lubed ones from the next gun show to try.

Thanks for the suggestions, guys.

 

[Walkalong]

Use a pan of Alox to dip the bullets in and keep it off the nose.... Use a lubrisizer.... Quit using cornstarch (or anything else), and clean your dies. Bump up the charge .1 or .2.

 

[floydster]

I shoot a ton of cast bullets in my pistols,9mm,38 Spl.,.357 Mag, 40 S&W, 38 Super and 45 ACP.
With all my cast bullets I put a few drops of Alox in a baggie with a handful of the bullets of choice, shake it up, lay out on wax paper overnite.
Very little leading in all my guns, any I do have, a few swipes with a Copper chore boy sleeve around a brush takes it right out.
Been doing this for years

 

[243winxb]

Lee Instruction from Link Below.

Mr. Lee said >

Cast bullet leading

A clue to what is causing the leading is where the leading first begins to appear. If it appears near the chamber, chances are that bullet diameter or hardness are the cause.

A diameter too small and/or too hard an alloy will allow high pressure gas to leak past the bullet, which erodes the bullet and leaves leading near the chamber.

If the leading first appears on the leading edge of the rifling (if you imagine the bullet being pushed through the barrel, you will note that one edge of the rifling does most of the work of imparting a spin to the bullet. This is the edge you see when you look through the barrel from the breech end) the bullet might be too soft, and/or the velocity too high.

If the leading appears in the second half of the barrel, the bullet is running out of lube. You should see a star shaped pattern of lube accumulate on the muzzle. This is an indication that there is a little excess lube.

Liquid Alox application

Best results in applying liquid alox are when the alox is heated before applying, or thinned with paint thinner. This makes it flow more easily, and results in a more even coat. One technique is to boil water and pour it into a coffee mug, and then drop the bottle of liquid alox into the mug for about five minutes.

Place your freshly cast bullets into something about the size of a Cool Whip bowl and drop a few drops of liquid Alox on the bullets. Mix the bullets around until they are all coated. Lay the freshly coated bullets on some wax paper to dry. Liquid alox will usually dry enough overnight to reload the next day, depending upon the humidity. Tacky bullets can be dusted with powdered graphite.

If you subscribe to the "more is better" line of thought, your coated bullets may never dry. Don't go for a "golden" color but rather just a light varnish. If you discover that your bullets are sticky the next day, you can get by with using a little less the next time. Keep reducing until the "stickiness" is gone by the next day.

If you are sizing your cast bullets, it is necessary to lube them first. Because the sizer will remove some of the surface of a larger diameter bullet, you may need to re-lubricate the bullets after they have been sized.

Many of our bullets are of the "TL" or Tumble Lube design. These bullets have many shallow grooves that are perfect for allowing Liquid Alox to adhere to a great amount of surface. It has been reported that the accuracy of these bullets is high.

 

[ArchAngelCD]

Usaually when you get leading farther down the barrel it is a sign of running out of lube on the bullet. Try some wax lube bullets with the same load and see what you get. I load a 124 gr. LRN wax lube bullet with no leading at all.

I agree, when the leading is down the barrel you are usually running out of lube before the bullet leaves the barrel.

 

[TonyT]

I have only used 147 gr. cast lead bullets in my 9mm with W-231 at 900 fps. I did not expereince any leadfing with commercial cast bullets which have been sized and lubed with grooove full of hard lube.

 

[Fatelvis]

As an earlier poster stated, where the leading occurs is very important in determining the problem. Is the leading towards the chamber or muzzle?

 

[greyling22]

I was running a similar recipe with leading issues for so long I assumed it was normal. then I started shooting paper and realized my bullets were tumbling because the rifling was stripping the bullets. I switched to a slower powder and most of my problems went away. then I went to a harder lead bullet and the rest went away.

Lesson Learned: just because the manual says you can run the load with lead doesn't mean it works with YOUR lead. or gun.

 

[LiveLife]

just because the manual says you can run the load with lead doesn't mean it works with YOUR lead. or gun.

True. When they test the "lead load data" I think they are only concerned with the maximum chamber pressure generated, not how much leading will result in your barrel.

 

[armoredman]

I use the 124 grain tumble lube Lee mould, and with LLA I get no leading, usually over mild loads of Accurate #7. I also don't cut the LLA, and warm it in a coffee cup full of hot water before use, swirl in a Tupperware bowl, (sorry, Mom), and dry overnight on wax paper. Works OK so far in my CZ pistols.

 

[MrWesson]

If your having problems with leading I would look at the alox first. I use a mix of xlox(cheaper same ingredients of lee alox) and Johnsons paste wax(carnuba floor wax) and it cuts down half the smoke and leading has disapeared in my 9mm's. Also bump your charge to around 3.5-3.8.

heres a link to the process to make the lube
http://castboolits.gunloads.com/showthread.php?t=67654

 

[PO2Hammer]

Instead of starch or talc, try powdered mica. I've used it with good results with liquid alox.
http://www.midwayusa.com/viewproduct/?productnumber=290522

 

[evan price]

I load Red Dot and 124 9mm's with 4.0 grains of powder. I think your load is too light. Also, back off the corn starch. I use powdered mica or graphite. Works great, no leading in my 9's with water-dropped wheel weight alloy and ALOX.

 

[rklessdriver]

I also think your load is too light. I don't know about the Lee Alox lube thou.

I'm loading 3.5gr Red Dot under a 124gr LRN (Missouri Bullet Small Ball).

No leading.

I tried to reduce my loading down to 3.0gr Red Dot once. It wouldn't operate either of my BHP's or my Star 100% and I got some very stubborn leading.
Will

 

[bdixon]

One thing I noticed that drastically improved leading in my sig's barrel was using a flat based boolit instead of a beveled base one. I have the same molds that you're using and I could never get them to work well. I ended up buying the 105 gr swc .358 lee mold (so I could use it in both 380 and 9mm) with a flat base and it works much better. I always water drop my 9mm boolits to keep them from being sized down in the brass.

I still get a tiny bit of leading towards the end of the barrel, just a couple small streaks, but it's good enough for me. 9mm has been really hard for me to figure out...