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ChirpinSquirrel
01-12-2012, 05:28 PM
Say I have a bullet mold for a 125 grain .312 bullet. Can I size down to .308 as well?

Also, it seems like I've read the molds drop bullets a bit wider too. So say I have a .308 mold, is it possible it will drop a .310 and I need to size to .308? And then use the unsized bullets for my 7.62x39/54R, and sized for my .308Winchester?

Helen Keller
01-12-2012, 05:33 PM
Say I have a bullet mold for a 125 grain .312 bullet. Can I size down to .308 as well
Yep just have em lubed up first.

and weigh a few here/there afterwords.

ChirpinSquirrel
01-12-2012, 05:42 PM
Cool, thanks

O.S.O.K.
01-12-2012, 10:41 PM
You will find that leaving them sized .001 to .002" over bore size will give best accuracy - so for your .308 caliber loads, size em .309 to .310" and for the 7.62x54 - .312" is fine.

I size .303 Brit boolits .314" (with appropriate mold) for use in them.

Lead boolits are very forgiving and you are almost never loading them anywhere near maximum pressure.

Also, Lee liquid alox makes an excellent sizing lube.

ChirpinSquirrel
01-13-2012, 01:21 AM
Awesome reply O.S.O.K. Iplanned on just rocking the Lee sizer dies and getting the Lee Liquid Alox. Supposedly you don't need to fill the grease grooves with harder grease. Is that true?

O.S.O.K.
01-13-2012, 10:06 AM
Thanks. I love the Lee sizer dies. That's what I've gone to exclusively. The bottom push feature makes for a very true/plumb sizing. I use the liquid alox for sizing and then apply another coat afterwords standing the boolets on their nose or base in a pan to dry. That is all that's needed for super lubricity. I love the stuff even though its messy.

(I say boolets because of this site: ( http://www.castboolits.gunloads.com (http://www.castboolits.gunloads.com) )

Once you get the boolets seated into the cases, you can whipe the lube off of the nose of boolits if you want.

If you are pushing your loads to beyond about 1500-1600 fps, then I recommend gas checked designs.

With the 30-30, I load 170 grain gas checks to 1950-2000 fps - just back of full pressure with great accuracy, no leading. The liquid alox is a great lube for rifles.

ChirpinSquirrel
01-13-2012, 02:14 PM
Right this second all I have is a Lee hand press (off your advice a year ago) but soon will upgrade to a turret press. But how difficult would this be to perform with this little tool?

O.S.O.K.
01-13-2012, 02:20 PM
Right this second all I have is a Lee hand press (off your advice a year ago) but soon will upgrade to a turret press. But how difficult would this be to perform with this little tool?

Oh, sizing those boolits wouldn't be hard at all - the hand press should be able to handle it easily. Glad I could help!!

noylj
03-19-2012, 12:58 AM
I have only been casting for 45 years, but I stopped sizing about 38 years ago.
I found that any sizing hurt accuracy. I found that any sizing of more the 0.003" destroyed accuracy. I found that MY guns preferred cast bullets larger than even 0.001" over groove diameter. I found that if my mold didn't cast close to the diameter I wanted, I either adjust the alloy or complain to the manufacturer. So far, in all those years, I have never complained to a manufacturer.
I prefer to neck-turn to have uniform neck case walls. In my cases, I could turn the neck down on cases that are too thick for my "large" bullets so they chamber and shoot great.
Except for being safe, reloaders need to experiment to see what works and then report to the forums.

Schuetzenman
03-19-2012, 06:14 AM
I would concure, sizing can hurt accuracy and having bullets larger than the groove diameter usually produces much better accuracy. The term Bore Diameter gets bandied about a lot, usually used incorrectly. Bore Diameter is the land top to land top diameter. Groove diameter is what people need to pay attention to as it is much larger than the bore diameter. Most modern barrels have .003" deep rifling. So for a .308 groove diameter barrel the bore diameter is going to be .302". .308" -(.003 X 2)= .302".

O.S.O.K.
03-19-2012, 10:06 AM
I found that sizing with my RCBS lubersizer hurt accuracy (it's apparently not plumb)... but sizing with my Lee sizer dies increases accuracy - yes, as long as you don't size down too much.

The bottom push ram squares the boolits up with the base.

O.S.O.K.
03-19-2012, 01:45 PM
greetings from Switzerland )

Hello. What's up? Why the reply here?