[Head Space]

I am new to Glock reloading but not reloading other pistols and rifles. When I read data in the 10mm forum I notice many like hard cast bullets. Along with the upper velocity ranges in a 10 is there a problem with leading? Are the cast bullets hard enough that leading isn't a problem? When casting one's own bullets what hardness do you look for? Finally is there a favorite solvent for barrel cleaning? Thanks for the look, I realize there are a lot off questions so thanks for the time.

[_The_Shadow]

Very soft lead can leave deposits at the higher pressures and velocities of 10mm. Having a bullet style that holds enough lube and quality of lube can assist with less fouling!

Usually bullets cast from wheel weight alloy is hard enough for the 10mm bullets. Some actually go a little harder alloy. Most of the time I don't get any leading, but sometime very minor streaks of fouling do occur. This cleans up easily with Hoppe's #9 and bore brush wrapped with a patch.

Bullet size helps and so does the bullet lube. I size to 0.4015" and have been using Rooster Lab Red Zambini lube, but I see it is not as readily availible. I may start using the Magma lube (cheaper and solid sticks) in my Star Sizers when I run out of the Zambini Red.

Sometimes it trial and success or error!

[dm1906]

As counterintuitive as it may sound, a larger diameter bullet will almost always cause less leading, than a smaller bullet, as long as the right lube is used. It isn't the contact of the lead bullet with the bore that causes leading (although it can with a poor bore quality). Bore leading is caused by adhesion. The methods of preventing/minimizing leading are isolation (coating, plating, jacketing), or ablative contamination (lube). Bare lead, lubed bullets use ablative contamination. Essentially, the goal is to use a lube to coat the bore to prevent particulate lead and lead vapor adhesion. It isn't necessarily a purpose of "lubrication", as lead in itself is an excellent lubricant, and doesn't really need help against smooth steel. By contaminating the steel surface with the lube, lead will not adhere to it. Anyone familiar with welding or plating can appreciate this. The process is ablative, as it is effective as long as the lube contaminant remains long enough, as it is burned off by the heat. Volume of lube is much less important than distribution. A smaller bullet in a bore will pass much more combustion gas around the bullet, creating a condition of heat exposure to bare lead and un-lubed bore surface, creating the leading (essentially plating the bore). A larger bullet (to a degree) will create a much better seal at the base, minimizing this condition. Bullet alloy and hardness changes this formula somewhat, and as it turns, is also counterintuitive. Bullet harness selection is more of a terminal performance factor than in-bore. Harder bullets resist deforming more, therefore are more resistant to gas sealing, and if the hardness is attained by the alloy, will have less exposed lead. Softer alloys are more malleable, but have more exposed lead. The reasons behind the means is much more extensive than just this. It's a science of chaos forced into compliance.

[21Glock]

Originally Posted by dm1906

As counterintuitive as it may sound, a larger diameter bullet will almost always cause less leading, than a smaller bullet, as long as the right lube is used. It isn't the contact of the lead bullet with the bore that causes leading (although it can with a poor bore quality). Bore leading is caused by adhesion. The methods of preventing/minimizing leading are isolation (coating, plating, jacketing), or ablative contamination (lube). Bare lead, lubed bullets use ablative contamination. Essentially, the goal is to use a lube to coat the bore to prevent particulate lead and lead vapor adhesion. It isn't necessarily a purpose of "lubrication", as lead in itself is an excellent lubricant, and doesn't really need help against smooth steel. By contaminating the steel surface with the lube, lead will not adhere to it. Anyone familiar with welding or plating can appreciate this. The process is ablative, as it is effective as long as the lube contaminant remains long enough, as it is burned off by the heat. Volume of lube is much less important than distribution. A smaller bullet in a bore will pass much more combustion gas around the bullet, creating a condition of heat exposure to bare lead and un-lubed bore surface, creating the leading (essentially plating the bore). A larger bullet (to a degree) will create a much better seal at the base, minimizing this condition. Bullet alloy and hardness changes this formula somewhat, and as it turns, is also counterintuitive. Bullet harness selection is more of a terminal performance factor than in-bore. Harder bullets resist deforming more, therefore are more resistant to gas sealing, and if the hardness is attained by the alloy, will have less exposed lead. Softer alloys are more malleable, but have more exposed lead. The reasons behind the means is much more extensive than just this. It's a science of chaos forced into compliance.

I've been using Froglube on my G21SF and will use it on my new Gen 4 20. Using homegrown WW cast bullets with LEE Liquid Alox. After my range session and some Froglube, on my G21, haven't shot the 10mm yet, I can make a few passes with my tornado, spiral brush and whatever little fouling is left from shooting is gone and she's clean as a whistle.
Froglube is the greatest at doing it all.

[Any Cal.]

I do hope that things continue to work that way for you, but would say that there is a chance things will change when you start shooting a cartridge with 2x the pressure and 1.5+x the velocity...

From the bit I have done, it seems to be an experimentation thing. Learn the principles, like DM1906 mentioned, then experiment with what you have until you find something that works, or comes close to it. My current lead load leads a bit, but in such a way that it does not seem to affect accuracy and is easily removed, so I am fine with it. You can get lead to shoot perfectly clean when everything is perfect, but it may require compromises on powder selection, bullet speed, etc.

[WeeWilly]

I don't cast, although Any's new casting thread has me leaning again.

In my store bought experience of loading and shooting lead, bullet fit seems to be the biggest factor, as long as I don't push the un-gas checked versions too hard.

I always seem to get less lead from semi's than revolvers, I suspect it has something to do with the throats, gaps and forcing cone variables.

For a round like a 10mm, at least the way I like to load them, gas checks seem to be the best invention since Cordite.

I just use some copper Chore Boy wrapped on a bore brush to get most of my lead out. For real disasters, that Lewis kit works pretty well.

[Yondering]

Originally Posted by WeeWilly

I just use some copper Chore Boy wrapped on a bore brush to get most of my lead out.

+100 on this. Best invention since smokeless powder.

If you're only shooting cast bullets, don't clean the bore with solvent; that just takes away the lube film from the bore. Scrub it with a brush, as WeeWilly described, and stop there.

[Yondering]

Originally Posted by dm1906

Bullet harness selection is more of a terminal performance factor than in-bore.

+1 on this too. I think most people don't realize this. Softer bullets seal the bore better. This is balanced, of course, by the need for enough bullet hardness to not strip out on the rifling. I've found air cooled wheel weights works pretty well for most 10mm loads, but leading is greatly reduced or eliminated by using gas checks too.