- Location
- In the shadows of the Rockies
Some range time today with a favorite rifle in the collection - my custom Sako AV 458 Lott with a Leupold VX-3 1.5-5x20mm scope. Feautures a 23" 1:14 twist Heym barrel. My hunting load is the 300gr TSX at about 2500 fps using 80.0gr of IMR4895 which a mild load in my rifle only.
The 300gr TSX has a b.c. of only 0.23 but this load shoots flat enough for use on heavy game out to 300 yards. The less expensive Hornady 300gr HP shoots to about the same impact point at 100 yards as the 300gr TSX.
For a further reduced load, I thought I would try the Speer 400gr SPFN bullet and 2400 powder to duplicate the standard 45-70 405gr load. No data in the Lyman Cast Bullet Handbook for the 458 Lott so I used the 458 Win. Mag. data for the 385gr cast bullet and 2400 powder for reference.
33.0gr of 2400 with dacron to keep the powder against the primer resulted in relatively low pressure but chronograph results were a bit erratic ranging from 1448 to 1535 fps, and affected accuracy accordingly.
Shot way low with the scope zeroed for the 300gr TSX hunting load. Aiming with the top of the thick vertical portion of the cross-hair at 100 yards it shot about zero and 3" right. Going to try Blue Dot next which produced excellent accuracy at relatively low pressure in my 45-70's with Remington 405gr jacketed bullets.
The 300gr TSX has a b.c. of only 0.23 but this load shoots flat enough for use on heavy game out to 300 yards. The less expensive Hornady 300gr HP shoots to about the same impact point at 100 yards as the 300gr TSX.
For a further reduced load, I thought I would try the Speer 400gr SPFN bullet and 2400 powder to duplicate the standard 45-70 405gr load. No data in the Lyman Cast Bullet Handbook for the 458 Lott so I used the 458 Win. Mag. data for the 385gr cast bullet and 2400 powder for reference.
33.0gr of 2400 with dacron to keep the powder against the primer resulted in relatively low pressure but chronograph results were a bit erratic ranging from 1448 to 1535 fps, and affected accuracy accordingly.
Shot way low with the scope zeroed for the 300gr TSX hunting load. Aiming with the top of the thick vertical portion of the cross-hair at 100 yards it shot about zero and 3" right. Going to try Blue Dot next which produced excellent accuracy at relatively low pressure in my 45-70's with Remington 405gr jacketed bullets.
