Shiloh Rifle Forums

beltfed wrote: ↑Tue Sep 24, 2019 7:47 am I suggest start with the idea of using a harder alloy for your bullets
especially if you are looking at long tapered ogive such as Elliptical, or even long "money" nose.
At least 16+1.
Then you will need to check out whatever ctg /Brass and chambering reamer dimensions
before you try to answer the question of the bullet/mold diameters with the chosen alloy.

Generally, good to have bullet a couple thousandths
larger than groove diameter.
For the most part, it is Very important to have bullet drive bands to fit fire formed brass
and any freebore in chamber. A bore ride front body should ride on the lands, not be engraved by them.
If the bullet is too small for the FF brass and freebore, you will get gas cutting.
Example:
I just went thru a first round of shooting available bullets thru my 38-50RH:
I have on hand two molds: they both cast bullets at about 0.376-0.377.
Groove dia via chamber cast is about 0.3773" or so. Fire formed brass is about 0.379" I.D.
First result: fair to decent accuracy.
BUT LEADING with initial smokeless loads and no wad under bullet .
This equates to gas blowby and cutting.
Now, I am into Paper Patch bullets with patch to 0.379 base bands and patch to land of about
0.366-0.367"


beltfed/arnie

Coltsmoke wrote: ↑Tue Sep 24, 2019 3:21 pm I would go with a .376 dia. If you go with a bigger dia. the lead on the base band where the rifling pushes through is moved to the rear of the base and forms little fins hanging off the rear of the base. The bullets do that anyway, why add more to it. A bigger dia. bullet has to squeeze down smaller and can contribute to friction leading on top of the rifling in front of the chamber. If a .376 bullet needs to bump up a thousandth I don't think it will have a problem doing so, but with your measurement I don't see why it would have to do that. Just my opinion, but you know what they say about opinions.