Appropriate uses for Linotype
- Thread starter S Mac
- Start date
You don't know that about the Roto's lino. Adding all four ingots at the same time told you nothing about the melt temp of the lino. Melting JUST the lino would tell you if it is really lino by the melt temp. 474 degrees, no slush stage, only a eutectic alloy will do that.
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smokeywolf
Well-Known Member
Rick, do you add any lino to COWW when you are casting 308s for the M1A?
No but I never pushed the velocity past about 1900 fps or so. Even then heat treating would be my first option, most of my shooting with it was air cooled CWW.
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Ian
Notorious member
The nice thing about the M1A is that the short-stroke piston gas system gives you a lot of options. One approach is to use a slower-burning powder than what is normally permissible, but load it down a few grains below starting pressure to keep the port pressure at 10-11K psi. Or use the "correct" powder (IMR 4895) right at or a grain below the NM loads and use a 170-grain bullet with a tapered nose...but cast it from a low-Sb alloy and heat treat it to at least 20 bhn. Getting accuracy out of an M1A with cast can be very tricky if you use the book standard cast bullet loading methods. I never could make a parallel-nose, bore-riding bullet work at all, they get bent right out of the gate.
Winelover
North Central Arkansas
And just how do you think I can get a accurate measurement using that procedure? Since, I don't have a PID and the dial type lead thermometers, just aren't capable of that fine of accuracy. Just maybe I need to give you one of Roto's 5# Lino ingots.
Fiddler
Active Member
Just curious, how hard are your jacketed/commercial ingots? My last batch of commercial pick ups came out at 15 b. The J ingots were ~10 b. The J pick ups also contained a lot of unknowns, obtained from the dueling tree so there will be some commercial mixed in.
S Mac
Sept. 10, 2021 Steve left us. You are missed.
My last question seemed to slip through the cracks. Any input?
Not excessive as much as not needed for most situations.
Most would use Lino and pure to mix up an alloy similar to COWW. Adding Lino to COWW will make a pretty hard alloy.
So much of this depends on what you plan to do with the alloy and what you need it to do.
Most would use Lino and pure to mix up an alloy similar to COWW. Adding Lino to COWW will make a pretty hard alloy.
So much of this depends on what you plan to do with the alloy and what you need it to do.
Ian
Notorious member
Most of us probably shoot alloy with 4% Sb or less in it, most of the time, so that's what we build our loads to match and why the recommendations to thin it down a bunch. I'm still of the opinion that the best use for Linotype is in the machines for which it was formulated. Most of the time there's no telling what state of depletion it is in, and based on John's experience we may not be able to count on Rotometals to get it right either, unless one or the other of them slipped and what he had was actually Superhard instead of Linotype alloy.
fiver
Well-Known Member
I think John got some terracorp magnum alloy. [2/6/92]
a little lino-type is a good thing to have around.
I bump my alloy with it from time to time for some applications, and mix it with ww's to make a pseudo lyman #2.
3 parts ww's and 1 part lino with 2% more tin added makes several of my bullets much more accurate.
[it comes in closer to 4/6 than 5/5 but I want to make sure I don't go over the tin amount]
I don't really gain a whole lot of diameter over ww alloy but I generally get enough to make a bore riding bullets nose take the rifling better and the extra strength helps them do their job of aligning and twisting the bullet into the barrel better.
you can always mix the mixed 3-1 alloy, at a mix of 1-1 with ww's, and add nothing else to come out with a nice 2/4 type alloy that casts easily and also has good strength.
when I'm looking for ultra accuracy I will quite often try several different alloy mixes [and add in water dropping] and observe the results.
a little lino-type is a good thing to have around.
I bump my alloy with it from time to time for some applications, and mix it with ww's to make a pseudo lyman #2.
3 parts ww's and 1 part lino with 2% more tin added makes several of my bullets much more accurate.
[it comes in closer to 4/6 than 5/5 but I want to make sure I don't go over the tin amount]
I don't really gain a whole lot of diameter over ww alloy but I generally get enough to make a bore riding bullets nose take the rifling better and the extra strength helps them do their job of aligning and twisting the bullet into the barrel better.
you can always mix the mixed 3-1 alloy, at a mix of 1-1 with ww's, and add nothing else to come out with a nice 2/4 type alloy that casts easily and also has good strength.
when I'm looking for ultra accuracy I will quite often try several different alloy mixes [and add in water dropping] and observe the results.
Ian
Notorious member
Right, I was thinking his 3:1 was harder than supposed to be, but he said 7bhn AC. Definitely something a lot more watered-down than Lino.
Winelover
North Central Arkansas
And......the AC value is down from 9 BHN, after 5 months. 
Would really like for that recipe to work. Twenty pounds (3 Pure and 1 Lino, in 5 # INGOTS) fits perfect in an empty 22# Pro-Melt. Kind of hard to make a mistake.
Plan is to empty that alloy from the pot. Melt a 5# Lino and record the melt temperature. Then add 3 pure ingots and cast some pistol bullets for BHN testing.......Rick doesn't like to use bullets with small meplats like Miha's 180 SiIL. See, if I get the same low BHN values. It's possible that I got a mis-marked ingot from Roto. BTW, the only ingots of theirs, I have, are either Pure or Lino.
However, that isn't a priority, right now......deer hunting started, last Saturday, runs till end of February. I only cast in the Winter/Spring and I do it outside, with the garage door open. My Pro-Melt runs on 220V and the only outlet is in the garage, for my air compressor.
It's been in the 90's with high humidity, for sometime. My garage, like the house, is ICF. When it gets hot, it stays hot. Last year, I had mold issues with my Chevelle seats, from trapped humidity.......use to open the garage doors in the early AM, to cool it down some. I also have a wooden "roll around" tool box that I was unable to open the drawers. I nixed that solution.
Would really like for that recipe to work. Twenty pounds (3 Pure and 1 Lino, in 5 # INGOTS) fits perfect in an empty 22# Pro-Melt. Kind of hard to make a mistake.
Plan is to empty that alloy from the pot. Melt a 5# Lino and record the melt temperature. Then add 3 pure ingots and cast some pistol bullets for BHN testing.......Rick doesn't like to use bullets with small meplats like Miha's 180 SiIL. See, if I get the same low BHN values. It's possible that I got a mis-marked ingot from Roto. BTW, the only ingots of theirs, I have, are either Pure or Lino.
However, that isn't a priority, right now......deer hunting started, last Saturday, runs till end of February. I only cast in the Winter/Spring and I do it outside, with the garage door open. My Pro-Melt runs on 220V and the only outlet is in the garage, for my air compressor.
It's been in the 90's with high humidity, for sometime. My garage, like the house, is ICF. When it gets hot, it stays hot. Last year, I had mold issues with my Chevelle seats, from trapped humidity.......use to open the garage doors in the early AM, to cool it down some. I also have a wooden "roll around" tool box that I was unable to open the drawers. I nixed that solution.
fiver
Well-Known Member
right.
you could do a 1-1 mix and see if the BHN comes out correct for ww's or hardball.
if it hits 15 then you just cut lino in half, if it gets to 11-12 you just cut terracorp 2/6 alloy in half.
the only other option is lyman no-2 alloy and that is almost impossible to tell apart from 2/6 alloy with BHN alone.
it melts similar to lino-type, so can cause confusion
[since that's your only real clue combined with the weight and BHN tests to tell them apart]
if you weigh it, it comes out real close to the 2/6 alloy too.
you could do a 1-1 mix and see if the BHN comes out correct for ww's or hardball.
if it hits 15 then you just cut lino in half, if it gets to 11-12 you just cut terracorp 2/6 alloy in half.
the only other option is lyman no-2 alloy and that is almost impossible to tell apart from 2/6 alloy with BHN alone.
it melts similar to lino-type, so can cause confusion
[since that's your only real clue combined with the weight and BHN tests to tell them apart]
if you weigh it, it comes out real close to the 2/6 alloy too.
