Marlin GA30 mold / bullet recommendations

[45coltnut]

Hello fellow casters,

I've just picked up a mint Marlin GA30 30-30 from my LGS. It has the micro groove barrel on it. This is my largest concern or at least question in what mold should I use. It seems I remember reading that's to groove barrels act differently than Ballard style rifling.

I would like to get a 150 - 180 grain has checked design. Preferably with cup points. Therefore, I'm looking at a NOE 311165 mold. But, before shelling $ for a custom mold I wanted to reach out and pick the minds of everyone here.

So, what do you shoot in your micro groove barrel? Also, just for my reference, please list your load and accuracy as well.

PS, I do want a medium to hot load. Hit, I'm after accuracy and knock down more than anything. Thanks in advance for all info.

[Old Coot]

You can shoot cast in micro groove barrels, but you have to do a couple of things: 1. Make sure that the bullet is at least .001 over groove dia. In fact .002 to .003 is even better and best accuracy will come from bullets cast, sized and lubed to fit fired but un-sized case necks. 2. Use nothing softer than Lyman#2 alloy. 3. I have heard good things about the RCBS 180 gr. flat nosed bullet and IMR 4350 in the 3030. I have not tried it myself though. 4. Any FLAT POINT 150 to 170gr bullet (gas checked ) will work well. I personally have gotten my best accuracy with IMR3031 and the Lyman 311041 173 gr flat point gas check. Slower powders like 3031, 4350, and 4895 reach peak pressure when the bullet is further down the barrel. They don't kick the bullet in the butt as hard at ignition as fast pistol type powders do. Since they "start" the bullet more gently they promote less skidding than faster powders. At least that is the current opinion going around like the flu. Brodie

[pls1911]

Coot's comments are well founded and should be heeded.

I have two NOE 311165 molds for Ranch Dog profiles and standard lube grooves.
Top Quality and a great investment.
Both my molds are 5 cavity gas check molds, no hollow points, and yes, I cast a year's supply for 3 of us when I get cranked up running 2 five cavity molds at once. NOE molds throw wonderfully consistent bullets.
I do heat treat my bullets and size at .312 which works for all the variations in older bores as well as early microgroove barrels.

These are pig pounding and accurate bullets.

Go ahead and get the 5 cavity mold...it's only a few dollars more, and your time saved with the increased production is well worth it.

For routine pig control and hunting I find it pretty easy to sort by weight into lots of +/- .5 grain lots, then combine the adjacent largest piles into +/- 1 grain lots.

[45coltnut]

Thanks for the suggestions. I sent my wish list in to NOE for a 311165. Hopefully, they'll have ready soon.

[Keyston44]

If you are just looking for a mold to try without a lot of expense you could try the Lee 150gr gas checked mold. I use that mold for a couple of Marlins that I have and it works very well.

Key