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smith
04-08-2018, 03:20 PM
this is going to be my first attempt to cast I am considering an alloy of 16 oz of super hard + 2 oz of 95/5 + 30 oz of lead which will give me 3lb of alloy for a 130 grain 300 blackout boolit at 2000 fps question 1)what would be the bhn. 2) should I use a gas check. 3) do you think this will cast well

Ateam
04-08-2018, 03:41 PM
What are you using for a pot? 3lb seems like a small batch to get much done with. I usually mix 20lb batches, but have a lee bottom pour...

Outer Rondacker
04-08-2018, 03:41 PM
Let me start by saying welcome to the forum. Next you should fill in your location as you might find some casting/shooting buddies in your area. Now for your questions.

1 no clue others will have to answer this one.
2 Yes at that speed but not a must if you are going to PC
3 Hard to say until you give it a try. A lot of factors in casting. Mold temp bullet cal so on.

With all that said and nothing answered do not get down and out. The answers will come from other members. I do have to add that I think you bullet is a bit light for 300blk and a bit fast.

All and all I think it will work if you pc it. No GC

smith
04-08-2018, 04:07 PM
Ateam I am trying to use the lead and 95/5 solder I have on hand to achieve a boolit in the 20 bhn range so the recipe will yield 3 lb of alloy multiply it by 7 and I will have 21 lb of alloy
outer rondacker thank you for the welcome what do you mean by pc and gc

dondiego
04-08-2018, 04:11 PM
PC= Powder Coat GC = Gas Check

Grmps
04-08-2018, 04:18 PM
smith- welcome to CB. If you decided to start casting to save money, forget it. You won't, you'll just shoot more.
Check the lead calculator link
Casting boolits (lead bullets) properly is a science, once you know the basics, not a hard science.
There is a lot of good information on CB. The Google search (top right of every forum page) is a gateway to all the knowledge on this forum. IF you can’t find your answer there ask the question (Please be as detailed as possible, pictures help http://castboolits.gunloads.com/showthread.php?344661-Capturing-amp-Posting-screen-shots I would be very surprised if there wasn’t someone on this forum that could answer ANY question you might have)
http://www.lasc.us/Fryxell_Book_Contents.htm
1. Boolits need to be cast .0005 to .003 over the slugged diameter of your barrel for accuracy and to avoid leading. If the fit is wrong nothing else will work right.
a. slugging a barrel (it is safer to use a brass rod or a steel rod with a couple of coats of tape to avoid damaging your barrel http://7.62x54r.net/MosinID/MosinSlug.htm
b. chamber casting https://www.brownells.com/guntech/cerrosafe/detail.htm?lid=10614
or pound casting http://castboolits.gunloads.com/showthread.php?356251-Pound-Cast-instructions-(for-rifle-chamber)
2. the right alloy needs to be used for the velocity and purpose of the boolit (don’t fall into the trap of going with to hard an alloy
Economical way to easily test lead hardness
http://castboolits.gunloads.com/showthread.php?355056-Easier-pencil-lead-hardness-testing
https://i.imgur.com/TGUQsIe.jpg
Some alloys harden over time
http://www.lasc.us/Fryxell_Book_Chapter_3_alloySelectionMetallurgy.ht m
different alloy’s different end sizes
https://i.imgur.com/emuBC2T.png?1
Lead alloy calculator
http://castboolits.gunloads.com/attachment.php?attachmentid=45784&d=1341560870
3. velocity the bullet needs to be pushed hard/fast enough to get the proper spin, have the proper velocity to accurately reach the target but not so hard as to be dangerous or strip the lead off in the grooves instead of spinning the boolit..
Powders range from fast to slow, you need to choose the right powder for your application.
Loading manuals list the best powders for certain calibers and boolit weights.
NEVER use any posted noncommercial load data without first checking to see if falls in the safe parameter for your firearm!! There are several firearms out there that can handle much higher pressures than others!!
Link to free online load data
http://castboolits.gunloads.com/showthread.php?337910-CB-load-data-online-sources

BUCKEYE BANDIT
04-08-2018, 04:23 PM
Smith,
Welcome, be advised this Rabbit hole has no bottom.But it sure is FUN !!! .

Walter Laich
04-08-2018, 06:19 PM
another welcome to the fun and games

dropping the bullets from the mold into water will add BHN to the bullets.

BE VERY CAREFUL ABOUT GETTING ANY WATER INTO THE CASTING POT, otherwise you will have a visit from the Tinsel Fairy and hot lead does leave scars (but then scars are like tattoos but with better stories)

jcourson
04-09-2018, 04:31 PM
That is a 15% antimony alloy. For comparison, linotype is only 12% and it breaks instead of bends.
Basically, antimony is hard, but brittle. You don't want too much.
LASC (http://www.lasc.us/SuperHard.htm) basically recommends staying under 5% except for rare occasions. The 6% hardball alloy air cools to 15 at 3 days, I would think water quenching or heat treating would easily get you above 20, but why would you want it? It wasn't that long ago that 12 was considered hard.
BTW, the alloy calculator would suggest that your alloy would get 23 hardness.

popper
04-09-2018, 08:10 PM
Way too much Sb. 4#Pb/0.5# S.H. = 3-4% Sb which will do fine if you WD it. I run a PB 142gr @ 2100 - MOA. You'll probably do better with a GC mould to start. Maybe one of the x39 moulds?

JonB_in_Glencoe
04-09-2018, 11:12 PM
smith,
Welcome to the website.

I think you may be putting the cart before the horse.
Casting and loading cast boolits for Rifle is kind of advanced. Do you have a pistol? I'd highly suggest you get your feet wet by casting some boolits for 38 spl or 45 acp, both are very forgiving and are great for a beginner to have success.

Also, if you haven't already, get yourself a good cast bullet reloading manual. The one I think is the best, is the "Lyman cast bullet handbook 4th Ed". Then read the first half of the book, that gives all the procedures and details to casting and loading for cast...Plus that manual has a great selection of loading data.
Good Luck.

PS...
If you are just looking for your specific answers about alloy blending and the pressures any specific alloy can tolerate and remain accurate...all the info you seek is at this link.
http://www.lasc.us/CastBulletNotes.htm

smith
04-10-2018, 05:31 PM
jcourson thanks for the reply from what i have read I need a bhn of around 20 to be able to push it at 2000 fps ( is this wrong I do have a box of hornady gas checks) I am trying to cast a boolit for target shooting that will match my factory load and bullets. I have fiocchi at 123grn,magtech 123grn, ammo both list a 2000 + fps and z max 110grn,barnes 110 gr,accubond 125 gr bullets I purchased a rcbs 7.62mm-130- spl mold I have a stock of pure lead (came from sheet lead in the sheet metal shop of my past employer I melted it down and fluxed it and poured it into a rcbs bar mold) and pounds of 95/5 solder I just ordered some super hard from rotometals if you guys can help me with a recipe using the stuff I have on hand it would be greatly appreciated also any advice on how better to ask this question and what board to post this on would also be greatly appreciated

popper
04-10-2018, 07:58 PM
8# lead to 1# of superhard. Is solder 5% Copper or Antimony? Anyway it is mostly tin. Use sparingly, less than 0.1# for this mix. You will need a gas check for that mould. Drop from the mould into ice water to get hardness (or 400F oven into ice water). I assume a bolt gun? It is NOT difficult. Load to low end or middle of jacketed loads, you'll get higher fps. I'd look into powder coat for lube. Simple, easy and low cost!

woodbutcher
04-10-2018, 08:29 PM
[smilie=s: Hi ya smith.Welcome aboard.Are you ever in trouble now.You done got the addiction,and it will never end:bigsmyl2:.A lot of great folks here,all will help.
Good luck.Have fun.Be safe.
Leo

smith
04-10-2018, 10:58 PM
Thanks popper my new rcbs pot arrived this afternoon now I have some place to start lots to learn thanks everybody for the welcome and info

Oklahoma Rebel
04-12-2018, 01:27 PM
search for alloy calculator, and play with it for a while. I do not see why 15 bhn would not work for 2000-2200fps, with a gas check, I have done that many times. for easy casting, maybe you should start with lymans #2 mix, which is 5% antimony, 5% tin, 90% lead. it will do fine, and unlike a 20bhn boolit, it should expand at your velocities, if it has a flat nose. as far as amounts of each to mix, you will have to play around with the calculator to figure that one out. it is in the "stickies" up in top of the alloys thread. good luck and have fun!- Travis Bright