Not happy with accuracy of cast lead bullet - .357 CN

[Mgr2]

Hi all.

I have been experimenting with cast lead bullets lately, in my .357 Big Boy Steel. The rifle is very accurate with XTP, FMJ and SP 158 grain bullets, over Winchester 296, Hodgdon HS6 or Hodgdon Universal powders. With high- and midrange loads with these powders it can print groups of 1.5 to 2.5 inches or better at 100 meters, from a rest. Very happy with the accuracy of the jacketed bullets. However with cast that is a different story.

I bought some (RCBS I think) 158 grain CN-PB (see pic below), sized to .358, and have tried various loads with the same powders, but accuracy is very poor. At best I get groups of 5 inches at 100 meters, with some flyers all over the target.

I have inspected the bullets very carefully, discarding those that showed any kind of defects, weighed them and sorted them in groups according to their weight, also measured the length of the cases and sorted those in groups. However even with carefully selected bullet/case/powder combinations I am nowhere near the FMJ bullet accuracy. Is this to be excpected from cast lead bullets, or is this particular design not suitable?




I also cast my own, and have tried out the Lee .358 158 RF, and saw a somewhat better accuracy, however not much.



Any tips would be appreciated .

[ssonb]

I have had some problems with home brewed bullets with my BBS 44. The 245 gr keith style worked very well until the velocity went above 1400 fps then I would get leading problems and the accuracy suffered. I finally Turned to powder coating the cast bullets and now I can detect no accuracy difference between the PCCL and copper jacket.....Now the 300 gr castings for some reason even with PC would not shoot right ,,,Some guns have their own preference for what bullets they like to digest.

[DAVIDF]

Rifles in particular can be very sensitive to the sizing of cast. Have you slugged or measured the groove diameter of your rifle? The common belief is to use cast bullets sized at .001 over the groove diameter. You can also call Henry and ask them what the groove diameter is supposed to be for Big Boy Steel rifles in .357. It may not be exactly what they say due to manufacturing tolerances, but it will be close enough. It may be that you need them sized at .359 or .36.

[tx gunrunner]

1st of all shooting cast bullets and jackets in the same barrel is a no no . The lead sticks to copper fouling and hurts the accuracy . I never shoot copper plate or jacket bullets in my cast bullet shoot . In my Glocks I have 2 barrel . 1 barrel for cast and 1 barrel for jackets . I hope this helps ...

[ssonb]

Like what txgunrunner said The PC keeps the copper and lead separate and saves a lot of hassle on having to pay attention to the BH of the cast bullet plus get to use the same barrel. I knock um out of the mold into cold water dry, clean and coat for the HV bullet and just lube the LV ones, Just cast whatever lead I have on hand into the proper shape and shoot much cheaper than even copper plated. For a .458 bullet even when I have to buy the lead (about 2.00 a pound) Approx 18, 405 gr bullets per lb, and the cost of the PC it runs under 10cent a bullet.

[Mgr2]

1st of all shooting cast bullets and jackets in the same barrel is a no no . The lead sticks to copper fouling and hurts the accuracy . I never shoot copper plate or jacket bullets in my cast bullet shoot . In my Glocks I have 2 barrel . 1 barrel for cast and 1 barrel for jackets . I hope this helps ...

Strange, but I have had no lead fouling whatsoever. And even with a thouroughly clean barrel the cast bullets are inaccurate.

[ditto1958]

I agree that you need to either slug your barrel, or experiment with bullets that are either .357 or .359 and see if that helps. I'd also try different weights of cast bullets.

[tx gunrunner]

Like what txgunrunner said The PC keeps the copper and lead separate and saves a lot of hassle on having to pay attention to the BH of the cast bullet plus get to use the same barrel. I knock um out of the mold into cold water dry, clean and coat for the HV bullet and just lube the LV ones, Just cast whatever lead I have on hand into the proper shape and shoot much cheaper than even copper plated. For a .458 bullet even when I have to buy the lead (about 2.00 a pound) Approx 18, 405 gr bullets per lb, and the cost of the PC it runs under 10cent a bullet.

I've been cast bullet since 1968 and I even make my own bullet that I use in casting bullets . If you really want to cast bullet the correct way get the book below and read it and NEVER believe anything posted on any forums it is 90% BS .

[DAVIDF]

1st of all shooting cast bullets and jackets in the same barrel is a no no . The lead sticks to copper fouling and hurts the accuracy . I never shoot copper plate or jacket bullets in my cast bullet shoot . In my Glocks I have 2 barrel . 1 barrel for cast and 1 barrel for jackets . I hope this helps ...

Perfect justification for a second Big Boy! My wife needs to read this

[ssonb]

Gonna have to get that book and add it to my collection of reference materiel . I have been reloading for over 30 yrs and casting for about 10, still lernin on the casting and love to experiment. I have no argument with the advice here and I will not post any info unless I have personally verified the results .

[tx gunrunner]

I normally shoot steel and only shoot paper for test targets and sight adjustments . The 1873 target is the 1st and only time I shot 50 yds on paper with this gun . This the 1st and last time I shot the Rossi . I sold it a week later . The 92 is super light but the 73 is super smooth and much faster then the 92 with a straight wall case in 38/357 . My 44-40 I shot in SASS/CAS for 16 yrs was smooth because of the bottleneck brass and 38/357 in a straight wall brass suck in it . The 73 with a short stroke in 357/38 straight wall case is KING . These are not target loads they are loaded for FPS not accuracy