Hard Cast vs. Marlin Microgroove

wapitiwhacker

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Is anyone out there loading hardcast bullets for a 45-70 with the Microgroove barrel? I've never dealt with cast bullets before, and would like to know what your secrets are. Gas checks? No gas checks? Leading? Accuracy? Are you using sized bullets for a known (slugged) barrel diameter or are you just ordering bulk .458 or .459 boolits? My goal is to find a load to push 405 gr. hardcast from a 22" Marlin Microgroove at around 1700-1800 fps with decent accuracy, and minimal leading. Thanks for your help.
 
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I can't help you regarding the 45-70 but I can at least tell you my experience with a 30-30 microgroove barrel. I water drop my bullets right from the mold. After a couple of days they test at 24 BHN. I run them through a .311 Lee Sizing die. I use felix lube & I also tumble them in LLA. My accuracy is about 1" at 50 yards depending on what type of powder I am using. My bullets have a shank to accept a gas check but I never had a need to use them since I get no leading at all.
 
I can't help you regarding the 45-70 but I can at least tell you my experience with a 30-30 microgroove barrel. I water drop my bullets right from the mold. After a couple of days they test at 24 BHN. I run them through a .311 Lee Sizing die. I use felix lube & I also tumble them in LLA. My accuracy is about 1" at 50 yards depending on what type of powder I am using. My bullets have a shank to accept a gas check but I never had a need to use them since I get no leading at all.

Whats your mix? 24 is high, only monotype has those numbers, linotype is 22:confused: point of note, I like 311 in 30-30 also , its accurate,
Hunting - try and get BHN 16 For expansion, and a clean kill, hard, it will whistle right through the length of a critter
 
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While i use and market many diff. bullets for the .44 and .444 Marlin, I have a new design bullet, designed by a customer for the microgroove .444s. It is a 250 gr. wide flatnose gas check (Wfn gc), made and sized to .432" ,which seems to work best in the microgroove barrels. I can also do it up in the more std. .430" diameter. Done up hard with linotype, you should be able to push it to max. velocities if required. One other note re: heat treating/quenching bullets, the hardness well gradually disappear and revert back to original hardness over time. Mono or Lino added to the mix will be consistently hard and stay that way.
 
linotype is 22:confused:

Linotype is more like 32 BHN. I get 24 with straight wheel weights without the chilling. would be interesting to actually compare a quenched bullet with one from the same batch just to see what the difference really is though.
 
Whats your mix? 24 is high, only monotype has those numbers, linotype is 22:confused: point of note, I like 311 in 30-30 also , its accurate,
Hunting - try and get BHN 16 For expansion, and a clean kill, hard, it will whistle right through the length of a critter

I use WW with 2% 95/5 (Tin/Antimony) solder. Believe it or not, one batch I cast tested 27 BHN. I'm assuming this was from the big truck WW I cast at that time. I hear they are supposed to be harder. I tried the same mixture but air cooled & these tested 14.3 BHN. However, I am using a Lee hardness tester so I don't know how accurate they are compared to the better quality testers. All I can say is that my bullets are working excellent for me.
 
When you say tin/antimony solder do you mean solder used for soldering wires. Just getting ready to start casting rifle bullets and all my lead is a mix of wheel weights, drain pipes, and lead sheets for x ray rooms. I assume i will have to harden this mix to put it through a 45-70.
 
Depending on calibre, barrel twist etc. I can run air-cooled wheel weights + 2%Sn at speeds from 1600-2000 FPS. Although W/W's vary a bit from smelt to smelt they usually BHN test at 12.5-14 on my Cabine Tree tester. This is the hardness I prefer for most hunting bullets. The same bullets can be oven hardened at different temps. to give me 19-24BHN. 19BHN is the hardest I want for any hunting purpose. Expansion is minimal with very hard bullets (or non-existent). Perhaps expansion is not so critical with my 45-70 but it certainly is in the 30, 32 and 35 calibers. I'll reduce speed if required for accuracy to maintain the softer bullet for expansion.

Frankly, I think the emphasis on hard cast can be overdone, particularly as it is such a loosey goosey term. It can mean anything from 16BHN to 35BHN and is not very descriptive or precise without the BHN numbers.

A while back I partcipated in a group test of hardness testers manufactured by different makers. Several testers of each make were used with bullets cast by the same guy at the same time using the same melt and the testers all tried to accomplish the testing on the same day (not possible for all due to slow mail). I think about 40 people participated in the testing. Whatever your machine tells you use that as a guide backed by field use as none of the testers were very consistent between machines of the same make at getting close to a laboratory tester with bullets from the same batch.

It doesn't make the test machines irrelevant , you just have to interpolate the results after target and/or hunting use. And, keep notes.
 
Is anyone out there loading hardcast bullets for a 45-70 with the Microgroove barrel? I've never dealt with cast bullets before, and would like to know what your secrets are. Gas checks? No gas checks? Leading? Accuracy? Are you using sized bullets for a known (slugged) barrel diameter or are you just ordering bulk .458 or .459 boolits? My goal is to find a load to push 405 gr. hardcast from a 22" Marlin Microgroove at around 1700-1800 fps with decent accuracy, and minimal leading. Thanks for your help.


Back to your topic.... Micro grove barrels need cast bullets to be oversize to shoot well. .459 .460 should yield good results.

Gas checks are usually recomened for 1500 fps and above so if your shooting for 17-1800 fps then I'd recomend them to avoid leading issues.

I buy Jae bok young's "crater" bullets in my malin 45/70 (ballard) and get excellent result. they're sized to .459 these bullets are hardcast (25bhn) and come with gc and do not prduce leading in my barrel. They are ment for big game hunting.


Cheers

Seabass
 
Back to your topic....

Whewwwwww, thanks Seabass:) I was leaning toward GCs, the Bullet Barn sells what sounds like a similar bullet to the one you are using. 405s at .459, GCs and triple lube grooves. I've never slugged a barrel before, guess I should try, for kicks if nothing else. I have heard the microgrooves tend to run a little on the large side. Maybe better served with .460s?
 
Whewwwwww, thanks Seabass:) I was leaning toward GCs, the Bullet Barn sells what sounds like a similar bullet to the one you are using. 405s at .459, GCs and triple lube grooves. I've never slugged a barrel before, guess I should try, for kicks if nothing else. I have heard the microgrooves tend to run a little on the large side. Maybe better served with .460s?

Slug your bore to find out... or buy a box of .459 and just try them out, if they don't work for you just send them to me!!!:D:D
seriouly though, either size should work.

Good luck
 
Howdy ; The Marlin is a modified micro -grove in 45-70 cal . IT will hold lead bullets OK, but after 25 rounds it fouled up a bit and lost some accuracy . I used 325 grain gas checked with unique that worked well at 200 yards or 405 plain base with unique or IMR 30-31 powder . Bullet size was mostly .458 some .459. It shot well enough at 600 yards in Raton New Mexico.
 
I have been shooting cast for about 6 months in my microgroove 45-70 marlin but have gone through about 300 rounds. I bought a large box of ~25bhn 350gr plain base bullet barn bullets from a friend who used to have a 45-70 and they gave me terrible leading. After shooting for an afternoon, the accuracy became horrible and it took me like an hour to clean the gun. I think they were sized .457" or .458" or something and worked fine in my friends ballard rifled barrel, but not in mine. I ordered a bunch of bullets from Ben Hunchak with and without gas checks and I have been really happy with them as far as leading goes. It's night and day, but I know these are at .459".

I'm not saying anything bad about the bullet barn, just the ones I had are not right in my gun. I am going to order a box of 200 405 gc's from them soon and make sure they are .459 or .460 this time. I bet they will be fine. They are close, they make nice looking products and they are cost effective...

I load the MT Chambers 340gr med hard hollow points to about 1050 or 1100 fps with Unique and the 420gr's to 1700 and 480's to 1500 with H4198. My 340gr "45 LC level" loads are a beautiful round, getting me a couple inches at 50 yards with factory sites and I'm sure they are whitetail capable. They barely kick and they make the rifle so much fun.

The 420's and 480's are ridiculous and not needed for the kind of hunting I have ever done. Even though I can only shoot about 3-4 inches at 50 yards with them, they feel like the hammer of thor and nothing hit properly with one will go very far. I have huge confidence in the rifle loaded up with the 420's and the last time I went woodcutting I found that they go about 18 inches into semi wet fir wood. I'll probably keep around a bunch of the 420's and 480's for bush carry bear defense when hiking into lakes, etc and make hunting rounds out of 405's or the 340's.

With properly sized bullets, cast ones are easy to clean up afterward and hit like a missile. It took me a little playing and experimenting, but not much to find what made me happy but I am not going to stop playing and learning.

I will buy bullets from both companies again. I have yet to ever reload a single non cast bullet for the rifle. I guess I'll go till I notice that remington bulk are the same price as some cast :)

I think I have more confidence in the cast ones. They have been around a lot longer and the buffalo certainly didn't like them much.
 
Great info unstableryan. Thanks. Bullet Barn is going to be in Chilliwack this weekend. I think I will order up some 405 GCs to start, save some shipping and go from there. I hope they shoot, you can't argue with the economics of cast.
 
wapitiwhacker, If going out to the Chiliwack Show, Bring along a set of calipers to measure the bullets with, If they are small tell them so, they advertise they are .459 hold them to that measurement.

Better to measure first and avoid dissapointment.

When OMA was still in Burnaby you could ask Al to size them to whatever your spec's desired. Ask bullet barn if they will do the same for you.
 
wapitiwhacker, If going out to the Chiliwack Show, Bring along a set of calipers to measure the bullets with, If they are small tell them so, they advertise they are .459 hold them to that measurement.

Better to measure first and avoid dissapointment.

When OMA was still in Burnaby you could ask Al to size them to whatever your spec's desired. Ask bullet barn if they will do the same for you.


Thanx, yes, they will custom size for you.
 
My experience with my Marlin Microgrooved barrels (45-70, 444, 30-30) is that you have to size at least 2 thou over slugged measurements or as big as will chamber. My .444 slugs at .430 and my best accuracy and low leading is when I run them fast and at .432. My 30-30's slug at .308-9 and I use .311 bullets and again at normal 30-30 velocities, water quenched 2% tin added and at least 1 month aged. Currently I have a hollow point 31141 mold that I can't wait to try out at the range to see how hard the bullet needs to be for proper expansion without exploding on impact.
 
Thanks Unstableryan, 10% off your next order.... folks may be interested to know that M.T. Chambers produces 12 diff. bullets for the 45/70, and while not made in a barn, they are tested behind one. Daily testing of bullets for accuracy, penetration, and on game ensures that you get what you ask for. I still use the old box full of frozen beef bones to test the big bullets and in the spring, i use the bones for bear bait. The bullets are made to order, in whatever size or hardness requested, remember that it is more important to have a proper fit of bullet to bore, then the actual bullet hardness. Bullets harder then Bhn 20 are actually counter productive on game as they don't expand reliably and when they hit big bone then tend to shatter or go right through without expanding. Bullets are avail. from pure lead and the 30-1 mixtures preferred by BPCR shooters right up to pure lino/monotype(recommended for target shooting only).
 
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