onondaga
posted this
16 October 2012
http://www.castbulletassoc.org/view_user.php?id=2102>Ben: Your bullets look like the sizing die only touched them on the mold parting line. They seem to be shooting fine, It may be that your alloy is soft enough to upset and fill the bore upon firing. That works, But really oversize bullets will work better. Bullets that drop .357-.3585” from a mold are not made bigger in a .360 sizing die. If you just tumble lube bullets that drop .360” from the mold that would be better.
Even if the bullets are a little snug to chamber with your loads, your rifle will size them with no pressure problem like oversize jacketed bullets pose. Cast bullet alloys are way softer than copper and even the largest will size fine upon firing.
Slugging a bore won't tell you your chamber size but will give you a good groove to groove bore measurement. .003-.005 larger than the G to G bore diameter or the largest bullet diameter that will chamber is usually the best you can do.
If you haven't slugged a bore before, search Google videos and watch 5 or more different "slugging a bore" videos. some are silly wrong but watch a bunch and you will get a good idea of how to do the slugging. Most importantly, use pure lead, a very clean bore that is then greased and a greased ball about .100” or more larger than your bore. A 45 cal. lead round ball is about perfect for a .357.
You can slug a chamber throat but it takes careful steps of driving the slug in to a specified depth from the chamber end, then driving it back out. This is well worth it if you really have difficulty fitting bullets. It tells the story and will end all guessing about bullet diameter needs for your rifle.
Chamber casting alloys are great too and the alloy material is re-usable.
You can even make a non reusable chamber casting mix with garden sulfur 3 parts and powdered graphite one part that is melted gently and poured into the chamber that has been prepared with mold release and plugged with rammed cotton just forward of the leade.. It is easy to do this on a Handi-Rifle compared to a bolt or lever gun that can get really messy if you over-pour.
You lucked out with your first bullet, but the measurements from slugging and chamber casting will eliminate the hardship of trying other bullets that are wrong for your rifle. Bullets that fit the throat with a gliding feel and are seated out far enough to engage the lands .010 past just kissing them are what really works with cast bullets in single shot rifles like the Handi.
Gary