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gilbertdodgen
Folks,
I’ve cast and sized (not with an NOE mould) for my Marlin .30-30 with microgroove rifling at .309 with gas checks (using Rotometals hard ball alloy, water dropped at BHN ~20). I can’t get them to shoot decent groups except at really low velocities (~1300-1400 fps with 9 grains of Unique). Would casting at .314 and sizing to .311 help, with gas checks? What NOE mould would you recommend?
Thanks for any advice you can offer.
gilbertdodgen-
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johnkotchie
bradtrojanowski
robertpedersen1
I ordered the 311041 mould. This is a favorite of Glen Fryxell for the Marlin, and claims that it shoots great with microgroove rifling. I bought my Marlin a couple of years ago new, and it definitely has MG rifling. Here’s a link to the Fryxell article:
I ordered the 311041 mould. This is a favorite of Glen Fryxell for the Marlin, and claims that it shoots great with microgroove rifling. I bought my Marlin a couple of years ago new, and it definitely has MG rifling. Here’s a link to the Fryxell article:
If it doesn’t say “Micro-Groove”, then it is something else. I’ve never seen your rifle, so you’re probably correct. But, for future reference….
Marlin marks barrels in three ways to denote rifling:
1. With “Micro-Groove” accompanying the ‘caliber’ marking.
2. With six to ten asterisks bracketing the ‘caliber’ marking (i.e.: **** .444 Marlin ****). This denotes “ballard” rifling.
3. With nothing but a ‘caliber’ marking. This denotes a middle ground – shallow rifling.The shallow rifling (deeper than MG, but not as deep as “Ballard”) is typically only seen on .30-30s, and, even then, typically only on the lower quality 336Ws. It’s nearly as shallow as MG rifling, but doesn’t conform to Marlin’s internal standards for MG rifling.
The 311041 NOE bullets shot great this weekend in the Marlin. They were cast with Rotometals hardball alloy, mixed with some magnum shot, and water dropped. They tested at BHN 21, were gas-checked, and lubed with LBT blue soft. I tried three different loads with three different powders. The best results were had with 30 grains of Hodgdon Leverevolution powder. Six rounds chronographed at an average of 2177 fps with an extreme spread of only 21 fps. They shot one ragged hole at 50 yards. Next best was 18 grains of 4198 (suggested by Fryxell) at an average of 1663 fps.
nanuk
I think the a confusing issue with MG barrels is it is not really the rifleing that is shallow, but the BORE is oversized. I have seen some that were supposedly MG but had only 8 or 10 lands…. IIRC, a true MG barrel should have something like 12-16 lands.
regarless, a proper sized bullet should shoot fine in them.
go as fat as the fired cartridge will allow you to finger seat and still chamber.
davidshimko
The 311041 NOE bullets shot great this weekend in the Marlin. They were cast with Rotometals hardball alloy, mixed with some magnum shot, and water dropped. They tested at BHN 21, were gas-checked, and lubed with LBT blue soft. I tried three different loads with three different powders. The best results were had with 30 grains of Hodgdon Leverevolution powder. Six rounds chronographed at an average of 2177 fps with an extreme spread of only 21 fps. They shot one ragged hole at 50 yards. Next best was 18 grains of 4198 (suggested by Fryxell) at an average of 1663 fps.
Just out of curiosity, what did you size these boolits to? .310″, .311″?
johnkotchie
bradtrojanowski
robertpedersen1
patrickhabowski
nanuk
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