my boolits weigh more, how to load?

[troy_mclure]

im casting the lee version of Lyman #31141. (.30/06 fp)

the manuals all list this boolit as 170gr, mine weigh out at 180gr(+/-1gr).

the next heaviest cast load is 187gr and is a pointed boolit.

how do i pick a load for this boolit?


i would like to use win748 with this boolit cause i have tons of it, and it is listed for jacketed bullets over 175gr, but its not listed for cast boolits over 175gr.

[chris in va]

Back off your powder charge a bit?

[sargenv]

load them with the higher bullet weight, otherwise back off 10% from the starting load of your bullet (even 20 %) and then work up from there.

[MtGun44]

Very small difference from that wt change. Back down the max charge by maybe 5% or
so. Heavy likely means more lead and less alloying metals. How hard is your boolit?

Rifles usually require a harder alloy than pistols.

[troy_mclure]

its so hard that when water dropped it was neigh inveunrable.

air cooled they are still sturdy, but not like the solid copper they felt like before.

[AZ-Stew]

Troy,

First, don't expect to shoot cast at the same velocity as you shoot jacketed. It can be done, but is what I consider an advanced specialty. If you're hoping to use 748 for that purpose, you might want to check some other data sources.

Second, the difference between your 180 gr boolit and the 170s for which you have data is between 5 and 6 percent. It's not a really big deal. Back off your starting loads 5-10 percent and you should be safe. Work back up from there.

You might want to try some other powders for cast. Usually the faster ones give best results. 2400, 4198 and others in that range are popular. You should be able to find data for your weight boolits in several manuals.

Regards,

Stew