Sizing die

[jpen]

Needing to order a sizing die to size and gas check my bullets. What size would I need to go with my Marlin 336 30/30?

[paul edward]

About .001 to .002" larger than the bore diameter of your rifle.

You need to slug the bore to determine what size die you need.

[runfiverun]

311..

[Iowa Fox]

311..

Yep, for sure.

[Scharfschuetze]

Once you get your sizing die sorted out, don't forget to order or buy an 30/31 calibre expander plug designed for cast boolits. Both RCBS and Lyman make dies to do such work.

[LuckyDog]

I suggest looking at NOE's expanders. I have a Lyman 31, but am getting the NOE because of the better options.

[Tatume]

311..

Agreed. Also, 0.310" works well in my Marlin M336 30-30.

I've been using the Lee C309-170-F 30 caliber mold and Lee reloading dies for many years. This is a very accurate combination. No need for any custom dies or plugs.

http://www.midwayusa.com/product/574963/lee-2-cavity-bullet-mold-c309-170-f-30-caliber-309-diameter-170-grain-flat-nose-gas-check

http://www.midwayusa.com/s?userSearchQuery=lee+30-30

[Scharfschuetze]

After going to the effort to size your boolits to .311," don't try sticking them in a neck without expanding and belling it. Factory Expanding buttons will leave you with an internal diameter (ID) of .304" or possibly less depending on the brand. Trying to stuff a .311" boolit into that will probably either compress your boolit to less than your intended diameter and it will probably damage it in other ways.

The proper size expanding die set should go part and parcel with your sizing die. In addition, it will slightly bell your case's neck to allow for easier seating of the boolit. Size your boolits and expand your necks.

The Lyman "M Die" is a good option and you may consider the .31 calibre size. That's what I use for .310 and larger boolits in the 30 calibre rifles.

The RCBS Expander Die is also a good choice and is the one I use the most. Here it is with various plugs from .307" though .311." This allows me to tailor my ID to the size of the boolit that I'm using. You'll want about .002" diameter less than your boolit diameter, although depending on the application that's not a hard and fast rule.

[44man]

I use Hornady dies, no special expanders and could care less. Make the boolit tough enough to not get sized when seating. I made my own flare tool. Need some flare.
I even made my own molds with a .301" nose and .311" drive.
This is what I got at 100 yards from my Remlin. Best group was 75% WW and 25% pure at over 1900 fps. Water dropped.157743 Top was just WW.