Lee liquid alox

[doc25]

I'm getting leading with lla in my 9mm. I've used it in rifle before without any problems. Do I need a thicker coat of it? Bullets are unsized out of a lee mould.

 

[c.t.smith]

You could try a second coat but probably you need a larger bullet or a lighter load.

 

[Spawn-Inc]

What's your barrel size and what are the bullets dropping at?

 

[LUTNIT]

It's not a Glock perchance is it? Their polygonal rifling is notorious for leading.

Slug your bore, measure the slugs (preferably with a micrometer), and go from there. Some 9mm molds are .355" and 9mm bores run from .354" to .356" (or thereabouts) so the bullets could be undersized.

 

[periculumnexnecis]

Try the 45 45 10 formula works better than alox alone, less messy too.

 

[doc25]

No not a glock. Cz75 older one. Will try slugging the bore and see what happens. As I understand it leading is usually caused by undersized projectiles. This is leading so bad that by the end of 10 rounds the grooves are full of lead. Does not seem to be an issue with my 357 although I do size the projectiles for that. The 9mm is using a 9mm mold.

 

[LUTNIT]

Leading can be caused by too soft an alloy for a given velocity, too hard an alloy for a given velocity, undersized bullets, too high a velocity for the twist rate, too high a velocity for the lube type, too low a velocity for the lube type, and many other things. It is commonly caused by undersized bullets but I find it most commonly caused by too high a velocity for a given hardness and twist rate (too high an RPM) in my own shooting.

I've heard of CZ's slugging odd sizes; both smaller and larger than normal depending on the age/model of the gun. Also see if you can slug just the throat and see if it's significantly different.

 

[Figure 11]

Doesn't alox have some strange properties, like a limited velocity range? I think the stuff smells horrible so I avoid it. I was shooting 38 (really) special at 1500 fps out of a rifle with rough-assed rifling today and there was no leading. No alox though, just bullets that fit and traditional lube.

 

[doc25]

While I didn't slug it yet I used my vernier on it and measured .350/.360. Almost identical to my 357. 360 is the groove and 350 is the land. Measured at muzzle. Gonna try some .358 cast in it and see what happens.

 

[LUTNIT]

A caliper can have an error up to +/- .002"
Measuring an ID using a caliper is difficult at best; I wouldn't rely on that measurement. If you tried to measure an ID for anything but a very rough estimate in a manufacturing shop using calipers, you'd get some pretty funny looks.

.358" in a .360" groove (if it really is .360") will likely cause issues. You want .001" to .002" above the groove diameter. If the diameter really is .360", you'd want a .361" to .362" bullet.
I'd slug the bore and get a real measurement using a micrometer to measure the slug.

 

[22to45]

To only slightly change the subject, I started powdercoating my cast bullets for my 4570.. I have to size them after I coat them, am very happy with them... I used alox for years, it was ok, but this is better.