Marlin 336 mold suggestion - micro groove barrel

[45coltnut]

Hello fellow casters,

I originally posted this by accident in the lever guns section. Probably better here.

I've just picked up a mint Marlin GA30 (same as 336) 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.

[Hurricane]

The micro groove barrel will shoot fine if you size the boolit to .311. I shoot Lyman 311041 (170 gr.), 311291 (170 gr.), Ranch Dog/NOE 311165 (165 gr.), and RCBS 30-180-FN (195 gr.), all very accurate. Some people size to .310 if you want to try it. Micro groove barrels shoot very good if you do not size the boolits to small. NOE has all 4 of these molds on their inventory page or you can buy 311041 and 311291 from Lyman and 30-80-FN from RCBS. My molds drop the boolits at .311 and I only use the sizer to be sure all the boolits are the same and lube them (if I don't use Lee liquid alox lube). SAECO also has a good mold #307 (180 gr) (comes out close to 190 gr. for me) that looks like a 311041 that grew up. Any of these molds would be a good pick.

[45coltnut]

Thanks for the info. I figured .311 would be good even if slightly large. I still need to slug it for my own knowledge.

[3leggedturtle]

I grew up using the Lee 113gr FP and 170gr FP, never really wanted or needed any other than those. I actually sized mine to .309 and never had any trouble with leading or accuracy. But I would go with as big as you can that will chamber. My rifle was a Marlin Glenfield 30A and I sold to a friend in 95, still regret it. Incadentally I shot the 113grFP to well over 2200fps with no leading or stripping.