Lube fouling?

[aussie460mag]

Hi all,

I have tested my new cast boolits in my S&W 460 mag and have observed some odd fouling in the barrel it starts about 2" from the forcing cone on the groves as they start to take shape (gain twist rifling) after about an inch the fouling then moves to the lands for the rest with the grooves being clean and shiny. anyone had this before? the fouling looked excessive but was easily removed patch out, after the barrel was clean the next 5 shots didn't really group, but once fouled up they pulled back into 4" at 25 using open sights

I am using lee 300gr GC mould (310gr lubed with alu GC) water drop WW alloy with 34gr of adr 2205 (4227?) for 1480 fps, I panned lubed with 3 parts bees wax 1 part lithium grease, then tumble lubed with lee liquid alox (figured i needed all the lube i could get as the lee only has 1 lube groove)

[geargnasher]

Gain twist in a .460?

Is the fouling lead, aluminum, or just black stuff? Can you show us a picture of the cleaning patches that removed the stuff?

Gear

[RobS]

Using straight WW's, sounds like it could be antimony wash or it could be a small amount of fowling from the aluminum GC. Hard to tell from this angle.

[aussie460mag]

Just black stuff and only on the lands (after the first bit in the groove), patches came out black, the grease also contained a small amount of moly and was dark grey in colour, there didn't seem to be any metal in the bore, it almost looked like burnt grease, i'll try and get a photo next range trip

[Huntducks]

Try burnt powder.....

Clean barrel vs dirty i'll take dirty every time for accuracy.

Ever heard the term (fouling shots)

[RobS]

Just black stuff and only on the lands (after the first bit in the groove), patches came out black, the grease also contained a small amount of moly and was dark grey in colour, there didn't seem to be any metal in the bore, it almost looked like burnt grease, i'll try and get a photo next range trip

If it's coming out with a patch and is not leading or causing accuracy decline then I wouldn't worry about it if you are liking your end results (the holes in the target). Also I don't think you'll need the tumble lube as an extra; there is plenty of lube groove for lube with the Lee design.

[Doc Highwall]

Ball powders leave a residue that is different then other powders.