Possible first sign of leading

[Clinton]

I've been casting boolits for about a year or so and thus far have avoided any serious leading. However after the last trip to the range I noticed the bore of my 1903A3 seem to take twice as many patches to get it clean and even then did not come out as clean as I like. Although I could see no leading in the bore with naked eye I believe I may have had a bit of leading. I ran some Chore Boy through the bore wrapped around a cleaning brush and this seems to have removed it because the patches are finally coming out clean. Does this sound like leading to you all?

Just so happens this also occurred right after hitting the highest velocity I have achieved to date with a cast boolit at 1750 fps. That is also where accuracy fell drastically apart. I've been tumble lubing with straight LLA (1/2 tbs per 100 boolits) and I'm thinking that maybe my lube has failed me. I'm going to relube that same batch and see if it is just a case of not enough lube. Thoughts?

[Yodogsandman]

Depending on your alloy, it could be antimonial wash. A velocity of 1750 FPS is very doable with Lee Liquid Lube. Are you allowing your boolits to age harden after casting? I like to wait at least 3 weeks (21 days) for Air Cooled for better BHN consistancy. If your velocity was a little higher, say 1850 FPS, I'd suggest oven heat treating and cold water quenching your boolits before lubing. Was that a chronographed velocity?

[Clinton]

They usually age for 1-2 weeks just because of my work schedule. I do water drop them as I cast them. The velocity was somewhere around 1750. I didn't record it because the accuracy had fell apart so badly.

[Yodogsandman]

1-2 weeks is fine for water dropped boolits. Yeah, lube some more.

So, what's your alloy?

Do your boolits fit good between the end of the case mouth and the beginning of the leade into the rifling lands?

[Clinton]

Just straight COWW. Yes the boolit fits the throat well and leaves marks all the way around the boolit from the case foward when chambered. The mold im using is not a tumble lube boolit mold and I've noticed the lube grooves were never "full" of lube but it hasn't been a problem up until this point. I doubled the amount of lube I was using and will see how they do now.

[Yodogsandman]

A slower powder could help, too. Are you maxing out, pressure wise, using a faster type powder?

I understand that Ranch Dog advocates dipping the boolit grooves in LLA and he's shooting at impressive velocities.

Check out Ben's Liquid Lube thread, I've run my 7.62x51 to about 2500FPS using it. Others, like 35 shooter, have done more testing and have been getting great accuracy up to 2500 FPS by triple coating boolits with it. Coat them first and size, then give them two more coats.

[Clinton]

No the best accuracy I've seen so far has been with IMR4895 and Varget. Good info thanks.

[Clinton]

More lube seemed to do the trick. Accuracy has come back even at higher velocities. Average velocity of this group was 1869. The bore is still being a bit stubborn to clean though. Maybe just something I have to live with. A few swipes with Chore Boy cleans it right up.
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