What Boolit Diameter for Pre-Marlin NEF .30-30 with Great Riling?

[Gray Fox]

I just picked up a very nice condition pre-Marlin NEF .30-30 with very sharp conventional rifling. I have a wide range of molds that will work starting with the 115 grain .32-20 boolit and going through 220 grainers. I'm wondering if any of you have a suggestion as to what boolit diameter might be best for this fine little rifle. I have a Skinner aperture sight ordered and plan to use it as a trail walking rifle this fall. GF

[BLAHUT]

Do a chamber cast or slug the barrel, only way you will know. That or spend a lot of time guessing, trying different sizes ???.

[Mk42gunner]

Do a chamber cast or slug the barrel, only way you will know. That or spend a lot of time guessing, trying different sizes ???.
^^^This.^^^

Failing that, my pre NEF H&R .30-30 did fine with 0.311" sized boolits.

Robert

[nhithaca]

As long as they will chamber with no issues, you can't go wrong with cast bullets sized @ 0.310-0.311" in most any 30 WCF gun. And, with a single shot you may be able to just neck size the brass for reloading. Saves the brass from stretching and may help accuracy.

[GARD72977]

I would use the largest diameter that would chamber.

[Gray Fox]

I just happen to have a Lee push through sizer in .311 so I'll give that a try with LLA. I've a batch of the 115 .32-20 boolits already lubed and sized at .312 left over from a batch I did for a friend who had one, so I'll run them through that sizer and load them over a moderate charge of red dot that will just about replicate a .32-20 performance. It would make a nice groundhog load. thanks for all the input.

Well, this one has no throat to speak of. The rifling is engraving the .300 nose just ahead of the front driving band of a dummy round with the 311041 bullet.GF

[Rapier]

Casting 101, first you slug the barrel. Always slug the barrel, size to actual grove diameter, do not crimp in a single shot.

[Iowa Fox]

I would use the largest diameter that would chamber.

Yep!
I've never sized a barrel in my life, I size to the throat. Years ago Nobade gave the best advice on this forum. Size to a light slip fit of your sized bullet in a un-sized piece of brass from your firearm.

[rockrat]

Nobade is correct. Brass will springback upon firing, a thou or two, so a light slip fit will give you neck clearance of the same for boolit release. Believe thats what the condom bullet shooters do in their competitions, look for .002" neck clearance, and turn the necks of their brass accordingly.