Starting cast reloading

[hoosierdome]

Looking at getting into making my own bullets. Going to start with my 45-70 and marlin 444. Have slugged both barrels there .459 and .432. Thinking that maybe I'd but some cast bullets of different sizes, shoot them and find out what would be the correct size bullet molds to buy. Would this be a good idea? yes, no

[tacklebury]

Might give you some insight into what your gun likes.    Typically, you should slug your bore and pick sizes .001 larger to ensure good gas seal.  I've been looking some at Western Bullet, because he has the mold number and manufacturer listed.  The one thing to keep in mind is that the alloy you use, ie. wheel weights, pure lead or #2 Lyman as examples, will harden at different speeds and can drop different sizes from a mold.  LBT's Veral states that if you send him slugs from your gun, he'll make a mold that will shoot well size wise from your gun based on the slugs.    If you aren't sure, there is some information on slugging in the NEF/H&R Centerfire FAQ IIRC. 

[bilmac]

I think you may be making the process a lot harder than you need to. You are talking lever guns here, not precision bolt guns. These are modern standardized barrels. I would say that the guys here can tell you what will work, and 9 times out of 10 you can bank on their recommendations working.

My own experience with the 45-70.  The Lee 450gr bullet doesn't work well in my Marlin. It even occasionally keyholes. My gun doesn't like Lyman 457191 very well either. It does best with 457124. My accuracy increased a lot when I started shooting the bullets unsized and hand lubed with white lithium based auto chassis grease. It will shoot about 2 1/2 " at 100 yds with a reciever sight with full house loads. With this bullet cast hard it will penetrate forever. I carried it as a bear stopper in Alaska. We couldn't find a single birch tree that would stop this bullet, we had to line up two to catch the bullet.

[Dezynco]

You probably will not find a bullet mold that is .001" oversized based on the measurements from your slugs.  The .001" is a "rule of thumb".  The .459" measurement you got, for example, is after the bullet "bulked up" to fill the grooves of the rifling.  Any good .457 or .458 bullet mold will do the trick for you, just vary the hardness or softness of the alloy to get the best accuracy.  Remember that the bullet's base tends to spread out when you light the fire, thus filling up the rifling. 

I'm a big fan of the 520gr. Lyman 457125 cast with 20/1 pure lead and tin.  That's probably a little harder than wheel weights (not sure), but wheel weights will probably work fine for you with almost any good bullet mold.

[jhalcott]

 With those big bullets an alloy of straight air cooled wheel weight MIGHT be a bit hard. I have used that alloy for a BOLT action 45-70 with great success. I never had any leading issues either! But cutting the WW with pure lead should help the bullet "bump up" to fill the bore. I would certainly start with WW and test it for accuracy and leading. HEY, YOU need the practice anyway ,right!?
http://www.lasc.us/CastBulletNotes.htm
  Go here for some more info on alloys

[hoosierdome]

Thanks I'll get a couple of molds so I can starting getting into casting.