Educational 30-30 cast day at range

[blixen]

I, novice boolit maker, loaded up some 30-30 rounds for my Marlin 336 (microgroove) with a 3-9x airgun scope and my Stevens 325B bolt action in which I just replaced the extractor.

I sized to .311 and .314 from the same Lee C-312-185 mold, (except beagled for the .314s). All gas checked. Paste wax/alox tumble lube.

Here's what I learned:
-- Neither rifle will chamber the .314s (which work great in my Argentine and SMLE).

-- The Stevens gave me 1.5" group at 50 yards with 7 grains of Red Dot with .311s seated way deep into case. But I had to crank the rear peep way up.

-- Stevens shot lousy (like 6 inches) with 10 grains of Trail Boss.

-- The Marlin put the .311s, pushed by 10g of Trail Boss, into less than an inch at 50 yards! (With jacketed projectiles, the Marlin has preferred just about anything to TB, including Unique and 2400.

-- I thought that I would put the largest diameter possible in the Marlin to compensate for the Microgrooving and assumed that .311 wouldn't be wide enough for good accuracy--BUT 1" at 50 is OK enough for me.

-- No soot on Red Dot cases.

--!! Microgrooved barrels seem to have a bad rep for poor accuracy with cast. But this particular old Marlin is good one--it groups better than most of my bolt actions. I can only put the accuracy down to it's rockin' blaze-orange camo sling (that's attached directly to the magazine tube, no less.)

I'm wondering if the Lee 312-155-2R boolit would work better in these short-throated rifles. I think its meant for the SKS, but has anyone used it in a thutty-thutty?

[sthwestvictoria]

Nice work and write up. Do you think the 312-185-r did not chamber because of OAL or diameter? I have been thinking about ordering one and milling the gas check portion off to achieve a 312 PB boolit, this would also shorten it, as other posters have stated Marlins have a short throat.

[blixen]

I think it won't chamber because of the diameter--I even seated them deeper than the .311s and it was no go.

[Marlin Junky]

--!! Microgrooved barrels seem to have a bad rep for poor accuracy with cast. But this particular old Marlin is good one--it groups better than most of my bolt actions. I can only put the accuracy down to it's rockin' blaze-orange camo sling (that's attached directly to the magazine tube, no less.)

I'm wondering if the Lee 312-155-2R boolit would work better in these short-throated rifles. I think its meant for the SKS, but has anyone used it in a thutty-thutty?

It's not just the length of the throat you need to look at. The Lee 312-185 might be a better choice for your particular 336 assuming a .302" bore. I would get a Lee 312-185 mold and a .312" sizer to compliment your .311" sizer. Once you get these buggers fitted, the challenge is over. We just had a good discussion about the variations of the infamous Marlin MircoGroove. I tried to post a link for you but it looks like the search function doesn't have all its bugs worked out yet... I seem to remember the thread in the "Cast Boolits" forum. Nevertheless, if you have a 336 made in the mid to late 60's, you've got the best verison of Marlin's MicroGroove. Count the lands and if it comes up 12, they are probably taller than the slightly less infamous new millennium "Deep Cut Ballard Style Rifling".

MJ

[blixen]

Thanks MJ,

Not sure of the date on my 336--does the subtract-the-first-two-digits from 100 trick apply?

It's a 1980--serial no. begins with 20.

Lee doesn't seem to make anything but .309, .311 and .314 sizers. I guess I could buff out .001 on a .311.

[sthwestvictoria]

I tried to post a link for you but it looks like the search function doesn't have all its bugs worked out yet... I seem to remember the thread in the "Cast Boolits" forum. MJ

Probably this thread:
http://castboolits.gunloads.com/showthread.php?171582-Cast-Bullets-in-Marlin-Micro-Groove-Barrel

and this thread was about 30-30 and trailboss:
http://castboolits.gunloads.com/showthread.php?144131-30-30-Trailboss/page3

[Marlin Junky]

Lee will custom cut a .312" die but I'd rather find someone with a better quality reputation to give my hard earned money.

From about '69-'71, the first two digits of the serial number designated the year of manufacture. Before that, Marlin used an alpha code. From about '71 to at least the end of the last millennium, (when I started to loose interest in Marlin) the first two digits of the serial number represented a count-down to the 21st century. In 1980, Marlin was still producing their .003" deep, 12-groove rifling and the bore diameter was very likely .302"; i.e., a good candidate for Lee 312-185 sized to .312".

MJ

[blixen]

I should be able to open the .311 sizer about .001 with a drill press, right?

[bruce drake]

just contact Buckshot here on the forum. He can make you a proper .312 pushthrough sizing die for about the same price as LEE and a faster turn-around than a custom order from LEE as well.

[kbstenberg]

1+ with Bruce. No offense meant. If you botch the reaming you got NO sizer. Yes you can use a drill press but its not the most common rout taken to enlarge a sizer. The stickies show the most common way.

[Mooseman]

I should be able to open the .311 sizer about .001 with a drill press, right?

NO...you cannot.
thats .0005 per side and no drill press is that accurate that I have ever found.

[blixen]

Thanks for warning me off. I'll check the stickies.