rifle alloy

[runfiverun]

the problem with 22's and water quenching is surface area and heat retention.
i use a 4/6 alloy made by cutting lino 50-50 with soft then adding 2% tin to the mix.
or by adding ww's to the lino 3-1 and adding 2% tin again.
this insures i don't go over the antimonial content with the tin.
i do water drop them but it's to cool them down and contain them, more than for the added hardness.

white eagle:
i just done a range report on my 223 and there is some good info in the thread.
it's in the cast boolits section.

[onondaga]

6:4 WW:Lino will be nice and hard,, high 20 something without quenching needed.
A small batch will let you know if it is too hard to size. Look out for that. If you can size it and gas check at that hardness you should be able to load at the 2700 fps you want.

gary

[Trifocals]

IMHO, WW is the most useful alloy we have. Add 1% - 2% tin, cast your boolits, size them, heat treat them at the appropriate temperature for 1 hr and quench in water. You can obtain any hardness from that of basic WW up to BHN of 28 - 30 and the boolits remain ductile, unlike linotype. Try it, you'll like it!

[white eagle]

Gary
Lyman lists that alloy(6#ww/4#lino) @15 bhn a #2 look alike
so w/q will put me over 20 bhn????
I think I need a wee bit more bhn my boolits are getting a bit nose deformed
when sizing and lubing
should I coat those little 22's w Lee allox there isn't a whole bunch of lube in the lube groove

[madsenshooter]

If the percentages of tin and antimony are known, I have an old typemetal chart I took from the American Rifleman years ago, that will give an approximation of the final hardness. Now if I could remember which book I stuck it in. Ah, found it, Sharpe was keeping track of it for me! This is just air cooled, not what's possible by water dropping or heat treating.

[onondaga]

Nose deforming on sizing can be helped with more BHN. The Lee sizer uses no nose punches and pushes bullets through from the base, That would work also. I use the Lee and tumble lube before and after sizing. If you are looking for 20+ BHN from #2 alloy, Put those bullets on a cookie sheet and in the oven at 350 degrees for 1 hour then dump them into a bucket of ice water. That will do it real well. You can do that before or after sizing but some lubes can get messy if they are already on at 350 degrees. Your 6:4 WW/Lino alloy has plenty of antimony and will harden dramatically with heat/quenching I mentioned. I haven't heard of LLA being applied after traditional groove lube, but I don't see any harm could come of it other than more stinking smoke out of your muzzle. Good luck and Merry Christmass.

If you haven't tried the 45-45-10 lube made with LLA/Johnson Paste Wax/mineral spirits for tumble lube, look it up-- no sticky, dries in 5 minutes and way less to zero extra smoke. I really like it and so do my rifles.

Gary

[onondaga]

You really use that chart! I'd like to see a video of how you make coordinates meet. In fact, I'd like to slap the guy that made that chart, the low percentages of tin and antimony never meet at a BHN# on that chart, the lines are all curvy and stop before you get to the percentages of tin and antimony that I use. I am dead stinking serious.

Gary

[madsenshooter]

Well let me see if I can get more of the credentials for you. It does work, no matter what your beef with it or the maker, the men who used it knew a hell of a lot more about their alloys than we do. I know, simply because I've been in printing long enough that hot type was just on it's way out. Let's see, "Adapted from: Type Metal Alloys" Weaver", Journal of the Institute of Metals. Making the coord's meet is just a matter of following the lines, which is a lot less bother than using the Lee Macroscope, and it get's me close enough to sail my boolits around 2450fps with a reasonable degree of accuracy. I guess you have to be one that thinks on a slant, nevermind the straight up and down. Think on the slant, yet follow the curve. It tells a lot, really. As an example, it tells that if you only use 2% Sn, you can add all the Sb you want, up to 24%, and it isn't going to get any harder than 18BHN. The curves are the BHN obtained, percentages of Sn are at the bottom, the most I've used is around 7%, and that makes some folks here aghast, but it works for me. Oh, actually the 3 formula in the upper left are plotted, 3 dots in the 25-28BHN range. The ends of the lines were still there, I just connected them with the red dashed lines. Some printers learn to read upside down and backwards too!

[grumpy one]

When you get above a certain level of antimony, the hardness increase you get in response to heat treatment decreases. Linotype hardly responds to heat treatment at all. After quite a lot of experimenting, the hardest alloy (after heat treatment) I have tested was about 1.6% tin, 4% antimony. Additional antimony reduced the effectiveness of the heat treatment more than it increased the hardness of the as-cast alloy. The 1.6/4 alloy heat treated to an average hardness of 33 BHN. The same heat treatment applied to an alloy with 8% tin and 7% antimony only produced 22 BHN - from an alloy that was 18 BHN as-cast. This is partly because tin moderates the natural heat treatment response of antimonial alloys - a 6.4% tin, 14.5% antimony alloy could be heat treated to 26 BHN (as-cast it was 19.5 BHN). The toughness (resistance to impact fracture) of all of the high antimony alloys was poor, though adding tin improved it greatly.

I suggest you work with a versatile alloy that responds strongly to heat treatment, and use various heat treatments to develop test samples of various hardnesses. That should let you find what hardness you need to get optimum accuracy and high velocity performance. When you know that, you will have another exercise to do, deciding how much toughness you need for your intended applications of the bullets. When you know both the hardness and the toughness required, you will know both the alloy and the heat treatment that will give you what you need.

[felix]

Very good, Grumpy. ... felix