Favorite lead hardness for Marlin micro groove?

[FergusonTO35]

I'm having all kinds of fun shooting cast boolits out of my .30 WCF Marlins with micro groove barrels. I'm using 115 and 150 grain boolits with gas checks, made out of a motley alloy of used boolits and wheel weights, water dropped and sized to .310. They're pretty hard, I would say BHN of 18-20. When I actually start hunting deer with these it seems like dropping the hardness down some would be a good idea, to help with boolit expansion and to prevent it from shattering on bone.

Those of you shooting the .30 WCF in micro groove barrels, what kind of hardness do you find works best? I have read in many places that the key to shooting cast in these is a boolit that is .001-.003 oversize and somewhat harder than the norm so that the tiny grooves will grip the slug. Do you find that extra hardness is needed, or that oversize boolits are the only requirement for micro groove?

[reloader28]

I'm shooting .001 over and using straight WW air cooled. Shoot good in mine.

I've also tried air cooled 50/50/2% and it seemed to shoot good too, tho I didnt try many yet.

[jlchucker]

I use the same mix for my Marlins in 30-30, 35 Rem, and 45-70. I mix straight wheelweight with approximately 20 percent pure lead. I flux this mix with parrafin wax (the kind that comes in blocks and is sold for canning food purposes) and have never had leading issues. The boolits are soft enough for game, and accurate enough for my plinking purposes out to 100 yd. Ferguson, I don't see anything wrong with your mix at all. It sounds like what you are getting right now is probably a bit softer that straight wheelweights--and Reloader28 is happy with that formula as well. By the way--I'm fortunate enough to have acquired, back when I first started out, a Lyman 311316 mold. I don't recall why, but after joining this website and read about the guys shooting 115 grain gascheck boolits out of a 30-30, I'm glad to have it now. There's people who've killed plenty of deer with a 115 grain boolit fired from a 32-20, and although I prefer a heavier boolit in the 170 grain range, I'd use the lighter boolit at close ranges if it's all I had.

[runfiverun]

the lower the antimony and waterdrop works very well.
you still have the soft malleable alloy and the external hardness to get them down the bbl.

[imashooter2]

My 30AS does best with about 20bhn and .311 diameter. The barrel slugs right at .308.

[pls1911]

50-50 WW and pure roofing lead.. Gas checked sized to .312, std lubed plus then lla/jpw
casts 9 to 10 BHN, heat treats to 23+.
Shoots like linotype but with enough retained plasticity to NOT shatter, but stay tough upon impact. Penetrates like n o tomorrow and knocks the stuffing out of everything so long as you have a flat meplat.
Never any leading up to 2000fps. Don't know beyond that.

[geargnasher]

The issue is accuracy. Water-quenched 50/50 WW/pure plus 1% tin is good to 2300+ fps in anything that will push it that fast, and MG barrels are no exception. Dilute it even more with pure lead for 1600-1900 fps performance on game. To get accuracy in the Marlins, you will need boolits that have noses to fit the oversized bores, and you need the driving bands to fill the chamber neck, that's the whole deal. I shoot .311" and .312" boolits out of my 336, which has a .303"x .309" barrel. I either use a Ranch Dog design or bump the noses to fit the bore.

Gear

[btroj]

With good fit alloy isn't a huge issue. I shoot stuff similar to 50/50 WW/pure that is water dropped all the time. Gives me hunting accuracy at any velocity I care to use.

I size to .311 and use the NOE version of the 311165 RD bullet. Works well in my Marlin.

[Wolfer]

I'm lucky, my 336 slugs .308 and my 311041 drops at .309. I shoot 1 WW- 2 PB with a scootch of tin to 1700 fps with 17 gr of 2400. Very accurate and no leading.
Gas checked and lubed with LLA sized .309

[FergusonTO35]

Forgot to add, I'm shooting the Ranch Dog 115 grain .32-20 and the Lee C309-150-F.

[6pt-sika]

When I had a heard of 30-30's a good portion were Micro groove . I originally started with sizing at .309 later went to .310 . A year or so after that i acquired a 311041 HP mold and when I tried sizing that one in the .310 die it would bump the nose to much . So I had a .312 die laying there and tried that , no bump and they loaded fine . So ever since that time all my 30-30's have been sized in the .312" die .

I also always used air cooled wheelweights with the 30-30 .

And it musta worked fairly well as lord knows I shot plenty rams at 200 meters .

[1Shirt]

I go with Gear! I water drop every thing! Just habit and convenience!
1Shirt!

[missionary5155]

Greetings
I use WW for my load development and plinking about.
When it is time for a hunting boolit I use 50/50 no matter what the most accurate velocity is. Even if 50/50 leads a bit you are not going to need a whole magazine full. One well placed round of 50/50 at 1500 fps or faster from 375 WIN & 41 mag on up to 45 -70 is going to tear one nice big clean leaker through the intended target. I size .002 over rifled diameter and there seems to not be any problem with skidding.
I hunt river bottoms and woods so my hunting ranges are normally 35 yards and less. Never lost any critter due to lack of 100 % penetration or a boolit that failed to expand.
In caliber 32-20 I do the same but in the 1873 Win I keep the velocity down to 1200 fps with a 115+ grain but have to use a .316 boolit for a fat throat. In the Savage Bolt rifle 1500+ fps is atainable and does a great job on groundhog size critters.
In the caliber .357 I go with the fattest heavy boolit that will chamber without undo lever pressure. Again I start with WW for all testing and plinking then cast up some 50/50 in whichever mold over 165 grains gives the best velocity/ accuracy combination.
Again at 35 yards accuracy is not a tough nut to crack. If I had to come up with 150 yard accuracy things may have to be different.
Remember to Vote Mike in ILL

[FergusonTO35]

Sounds good. I water drop everything as of right now but I'm going to do some experimenting before I start hunting deer with cast boolits.

[makicjf]

My 336 30/30 shoots well with a lee 170 gc flat nosed straight ww waterdropped and gas checked sized to .311. bore slugs about.309. The hunting load is 30 grains imr 3031, the cowboy load is 10 of unique. No leading, plenty accurate and the hotter load rolled the hog in my picture down the hill he was on from 80- 90 yards out. He flopped twice and died. I've toyed with the idea of air cooled wheel weights for better expansion, but the loads shoot well and seem to kill well too. Thus I am leary to change anything.
Jason