oldandslow
08-01-2013, 02:16 AM
Greetings casters, 8/1/13
My problem was with the nose of my 30-06 boolit, AccurateMolds #310-180-F (gas checked), twisting off at velocities of 2200 ft/second. The same boolit would hold together and retain 96% of its weight at 1845 ft/second when recovered from water soaked paperback books (Jane Fonda' My Life My Way, SAT Study Guide, Federal Tax Code, etc.) bought for $0.50 each at my local Salvation Army store.
Many helpful posters have recommended various options such as keeping the velocity down, adding more Tin (Sn), Antimony (Sb), arsenic or Copper (Cu). Below are the results with increasing tin, antimony and copper percentages in my base alloy.
Rifle and load data- Howa 1500 30-06, 1:10 twist, with 200 rounds of jacketed bullets before lead testing. Powder-40 grains 4064, Winchester LRP, Winchester Brass, boolits are 0.010" off lands.
Alloy type
Base alloy- 97.1% Pb, 2.22% Sb, 0.435% Sn ------ retained wt.38%----Ice water dropped----BHN 20.9
Base alloy plus 2% Sn-----------------------------------40%---------------70 deg. WD-----------14.3
Base alloy plus 2% Sn ----------------------------------63%----------------IWD------------------16.6
Alloy #1- 94.9% Pb, 2.7% Sn, 2.3% Sb, 0.11% Cu---73%----------------70 deg. WD-----------15.4
Alloy #1-------------------------------------------------58%---------------- IWD------------------15.4
Alloy #2- 93,5% Pb, 3.9% Sn, 2.3% Sb, 0.27% Cu---85%---------------- 70 deg WD-----------15.4
Alloy #2------------------------------------------------- 71%----------------IWD-------------------15,4
Alloy #3 92.5% Pb, 3.7% Sn,3.5% Sb, 0.25% Cu----48%-----------------70 deg WD-----------15.4
Alloy #3 ------------------------------------------------56% ----------------IWD-------------------13.4
Alloy #4 83.65% Pb, 8.2% Sn,7.7% Sb, 0.45% Cu---79% ----------------70 deg. WD-----------15.4
Alloy #4 ------------------------------------------------61%-----------------air cooled-------------14.3
So in summary the base alloy with almost no tin functioned poorly. Adding tin helped moderately and adding copper to make the tin plus copper percentages about equal to the antimony percentages helped a bit more. However I don't see any alloy that meets my goal of a consistent retention of weight high enough for both my paper punching and pig hunting at velocities of 2200 ft/second. I think my mold's long, heavy and unsupported nose is too heavy for medium velocity 30-06 loads. I've ordered another AccurateMold, # 310-185-L-gas checked with much less nose forward of the driving bands and will give it a try.
Any other comments or suggestions?
thanks- oldandslow
My problem was with the nose of my 30-06 boolit, AccurateMolds #310-180-F (gas checked), twisting off at velocities of 2200 ft/second. The same boolit would hold together and retain 96% of its weight at 1845 ft/second when recovered from water soaked paperback books (Jane Fonda' My Life My Way, SAT Study Guide, Federal Tax Code, etc.) bought for $0.50 each at my local Salvation Army store.
Many helpful posters have recommended various options such as keeping the velocity down, adding more Tin (Sn), Antimony (Sb), arsenic or Copper (Cu). Below are the results with increasing tin, antimony and copper percentages in my base alloy.
Rifle and load data- Howa 1500 30-06, 1:10 twist, with 200 rounds of jacketed bullets before lead testing. Powder-40 grains 4064, Winchester LRP, Winchester Brass, boolits are 0.010" off lands.
Alloy type
Base alloy- 97.1% Pb, 2.22% Sb, 0.435% Sn ------ retained wt.38%----Ice water dropped----BHN 20.9
Base alloy plus 2% Sn-----------------------------------40%---------------70 deg. WD-----------14.3
Base alloy plus 2% Sn ----------------------------------63%----------------IWD------------------16.6
Alloy #1- 94.9% Pb, 2.7% Sn, 2.3% Sb, 0.11% Cu---73%----------------70 deg. WD-----------15.4
Alloy #1-------------------------------------------------58%---------------- IWD------------------15.4
Alloy #2- 93,5% Pb, 3.9% Sn, 2.3% Sb, 0.27% Cu---85%---------------- 70 deg WD-----------15.4
Alloy #2------------------------------------------------- 71%----------------IWD-------------------15,4
Alloy #3 92.5% Pb, 3.7% Sn,3.5% Sb, 0.25% Cu----48%-----------------70 deg WD-----------15.4
Alloy #3 ------------------------------------------------56% ----------------IWD-------------------13.4
Alloy #4 83.65% Pb, 8.2% Sn,7.7% Sb, 0.45% Cu---79% ----------------70 deg. WD-----------15.4
Alloy #4 ------------------------------------------------61%-----------------air cooled-------------14.3
So in summary the base alloy with almost no tin functioned poorly. Adding tin helped moderately and adding copper to make the tin plus copper percentages about equal to the antimony percentages helped a bit more. However I don't see any alloy that meets my goal of a consistent retention of weight high enough for both my paper punching and pig hunting at velocities of 2200 ft/second. I think my mold's long, heavy and unsupported nose is too heavy for medium velocity 30-06 loads. I've ordered another AccurateMold, # 310-185-L-gas checked with much less nose forward of the driving bands and will give it a try.
Any other comments or suggestions?
thanks- oldandslow