help with the 41 mag

[Southpaw 72]

Complete leading disaster. Straight wd ww , Jakes scarlet ceresin lube. 17 gr. of aa9. About 1345 across the chrono. Been using jakes in my 454 with decent results, but it is a complete failure in the 41. Bullet is rcbs210 swc. Too hot of a load for the alloy, or different lube?

[felix]

Load is OK for a "normal" lot of WC820/AA9. ... felix

[x101airborne]

throat to bore difference.
Has nothing to do with the boolit its self.
Slug the bore, measure the throats. Open as needed. Then fire lap the bore. I just did this to a used blackhawk I purchased and it helped immensely.

[Southpaw 72]

Boolits are a snug fit in the throats, about .015 over bore size. How do you firelap? Or is there a way I can polish the bore?

[bruce381]

try diferent lube I shoot 41 same boolit with WW and use Lars BAC sized .410 no problem tho I use WW 296 @ 17-18 GR

[geargnasher]

Add 1% tin next time. Did the boolits age before you shot them? Scrap that lube and make some of Felix's stuff or use BAC as has been recommended. Personally I'd go with ACWW, but I've also shot some amazing groups at long range after reluctantly trying some really hard, well-fitting boolits.

Gear

[leadman]

I shoot a 41 also. I water drop and use gas checked boolits for that velocity. You can invert a gas check in the mouth of the case and let the boolit push it in when it is seated. I have done this many times. Dave AScovill worte this up in Handloader many years ago.
Also a little slower powder like 296/110 will work better.
I use Carnuba Red for most of my boolits. When I go for high velocity I use LBT Blue Soft.
I have shot the Lee 240gr plain base over 1,400 fps with no leading.

[Southpaw 72]

Add 1% tin next time. Did the boolits age before you shot them? Scrap that lube and make some of Felix's stuff or use BAC as has been recommended. Personally I'd go with ACWW, but I've also shot some amazing groups at long range after reluctantly trying some really hard, well-fitting boolits.

Gear

I waited two weeks before I loaded them. I'll try different lube before I start tinkering with my alloy. What does the tin do to the alloy?

[plainsman456]

The tin makes it a little harder.
I shoot the 41 in a Blackhawk and a Marlin 1894s and use 2500+,with the boolits made out of ad/ww.

[geargnasher]

Tin forms an intermetallic bond with antimony in approximately equal proportions, making an intermetallic "element" called Sb/Sn with unique properties. The short version is a little tin toughens the alloy slightly and reduces the brittleness of the Sb/Pb alloy a whole lot, which in turn reduces it's tendency to fret off small particles in the bore from simple abrasion. Under-tinned ternary alloy tends to create and "antimony wash" in the barrel, and is also more prone to actual leading from either metal-to-metal friction or gas abrasion/deposition from a leaky fit in the barrel.

Your age time is plenty. If the antimony goes below 2%, often much more time is needed. What you have is probably ready to shoot the next day or two.

Gear

[fcvan]

The worst leading I ever had was with a S&W M57. I tried a different lube and it went south. I scrapped that lube and went back to my old standby. The M57 was relatively new then so I shot a lot of 1000fps loads with gas checks to help 'break her in.' Now she shoots plain based at 1250 with good old Javalina or my home made loob. I still use gas check loads in my Marlin but never had a problem with leading even when it was new. Frank

[Southpaw 72]

Tin forms an intermetallic bond with antimony in approximately equal proportions, making an intermetallic "element" called Sb/Sn with unique properties. The short version is a little tin toughens the alloy slightly and reduces the brittleness of the Sb/Pb alloy a whole lot, which in turn reduces it's tendency to fret off small particles in the bore from simple abrasion. Under-tinned ternary alloy tends to create and "antimony wash" in the barrel, and is also more prone to actual leading from either metal-to-metal friction or gas abrasion/deposition from a leaky fit in the barrel.

Your age time is plenty. If the antimony goes below 2%, often much more time is needed. What you have is probably ready to shoot the next day or two.

Gear

Thanks for the explanation in laymans terms, a metallurgist I am not.

[Mavrick]

You can listen to Gearnasher, the extra tin will also ease casting.
I use the RCBS 210 quite a bit, and have one of the cavities HPed. My leading almost stopped when I started sizing to .413, in my M57 6". I've dip-lubed with 45-45-10 and Felix's, but mostly use BAC and Red Carnuba. Red Rooster and Angel Blue have gone downrange in velocities of 850-1000fps with Unique and 1275-1425fps with #9, 2400 or WW296.
Have fun,
Gene