Have a 66-1 that I wish to try at low velocity with Wheel weight cast bullets sized to .359". The cylinder ball ends measure .3575" from a pushed through slug.

Is the .359" bullet safe to shoot in this situation? Haven't measured the 5-groove bore. Anyone have a guess on that number?

Thanks

If you are casting pure wheel weights IMHO you won't have any problems with shooting a cast bullet that is sized to 0.359". As usual, start at the lower end of the powder weights and work up. ....

+1 on Big Cholla's post. .359" bullets should give no trouble in a 66, either in .38 or moderate .357 loads.

Larry

It will be perfectly safe to use your .359 bullets but you may find that
your model 66 chambers will be a very tight fit for your cases with
.359 dia bullets in them. Load a few and try them before you end up
with a lot of handloads that will not chamber in your 66.

Its safe but pointless shooting 0.359" bullets, the throats will size them to 0.3575". As noted, a softer bullet may bump to fit your bore, but low pressure loads with clip ww probably not. If the bore is 0.357", it wont matter. Size to 0.358" & go shoot.

__________________
NRA Cert. Inst. IDPA CSO

+1 on the above with the "Soft Bullets" but.........

you may get better accuracy if at .358 dia, with a little less friction and pressures.

Stay safe.

It's pretty hard to accurately measure a soft slug that was
pushed through a five groove bore. .357-.358 would be a
good guess but it really doesn't matter. I've used .359 dia
cast bullets of the current magma type cast of very hard
alloy in my .38 and .357 plinking loads. I ordered them
from an online vendor in .359 dia thinking that accuracy
would be improved, it wasn't, one of many learning
experiences along the way. As I said above chambering can
become a problem. Some handloaders may not realize that
a revolver cyl can be used to size their cast bullets. Any hard
cast lead bullet is way softer than your steel revolver cyl. I
suggest that you choose one chamber of your cyl, clean well,
tap your bullets through gently from back to front with a
soft rod like wood or nylon, load and shoot and don't worry.

I would size to .358 if I had that diameter die. .359 is the closest I've got on hand. The loaded niners drop right in.

Thanks all for your responses.

Yep; you will always get best results from the largest cast bullet diameter that will still allow easy chambering of the loaded cartridge. Pressure will not be affected.

Flame on!!!