Necessary to Size These?

[RedRiver]

My lee .45 230 grain RN mold casts to .452, except for the very base of the bullet, that is .455.

My Springfield barrel slugs out at .4505 in the grooves. Will that larger diameter at the very base cause me issues if I don't put them through the sizer?

[243winxb]

A loaded round may not chamber. Some springfields require .451" diameter to fit the leade of the barrel. The Lee may needed to be seated to a short OAL to chamber. Load 3 dummy rounds, see if the chamber. Mixed headstamp brass may add to the problem with large diameter bullets.

[Bzcraig]

Sure seems like you'd have to bell the case mouth way too much to keep from shaving the boolit when seating. I would size to 452 which will also give you a nice round boolit with a good fit to your bore.

[beagle]

I'll agree on the belling. If you can get them to enter the case mouth without shaving, when you seat, the base will probably be swaged down by the case. I've noted this in both 9mm and .30 Carbine loads./beagle


Sure seems like you'd have to bell the case mouth way too much to keep from shaving the boolit when seating. I would size to 452 which will also give you a nice round boolit with a good fit to your bore.

[runfiverun]

I got nothing post 3 and 4 hasn't covered.
you might swage the base down in the crimp die too but you'll probably distort it in the process.
I'd just size them and be done with it, or mill the mold down.

[rancher1913]

when in doubt, size :Fire:

[JonB_in_Glencoe]

SNIP... except for the very base of the bullet, that is .455.

RedRiver,
Welcome to the forum,
If that's just flashing, it's probably no big deal and could possibly be rectified by better fitment or adjustment of the sprue plate.

[mdi]

Are the bullets "bell bottoms" (taper to .455") or is there an edge as Jon B suggests? If there is a short taper, I'd size them, if it's "flashing" I'd fix the mold...

[DougGuy]

You would definitely want to size those, as even a few tenths misalignment in the parting lines might create enough interference in the throat that they won't plunk.

Another thing, Springfield and many other mfgrs don't put enough freebore in the throat of the barrel to chamber a round seated out to the COA specified in the loading manuals, and if they do have much freebore, it is often no bigger than .451" which creates problems galore for using cast boolits in the gun.

Very typical to need the barrel throated for using with .452" cast boolits but it is an inexpensive, one-time fix that will make it run with cast like a swiss watch afterwards.