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View Full Version : New to casting. Advice please



Tango2020
08-10-2011, 09:08 PM
I have lurked for some time and have learned much ( I think ). Let me explain where I am at this point.
Loading for an XDM 40. Shot a few K of missouri bullets with minor leading. Loading 180g with 5.1g of unique.
I slugged my barrel out at .400. I have now bought a Lee 10 lb production pot, 175gr 2 bullet mold and a lee .401 sizer and lee hardness tester.
I mixed the Alox w/Johnson wax and OMS. 40/40/20 for lube.
Batch 1
Pure WW
Bullets were beautiful, after I got the hang of it and air cooled. BHN was around 8.5. I lubed and sized then relubed. Loaded over 5.1 of unique.
Results: bad leading
Batch 2.
Added 700 gr I'd pure tin to the 10 pound pot. 1% I estimate. Gave me a BHN of 12.5.
Sized but haven't loaded yet.

If the barrel is .400 then .401 should be a good fit. Right?
I know the fit is more important than the BHN but I'm anxious to get my formula right and start production.

Got 8 buckets of wheel weight on standby.

What are your thoughts?

Springfield
08-10-2011, 09:16 PM
I'm surprised you BHN went up over 4 points by just adding a small amout of tin. How do you measure hardness?

Tango2020
08-10-2011, 09:26 PM
One of these.

http://www.midwayusa.com/viewproduct/?productnumber=731364

462
08-10-2011, 10:21 PM
Tango2020,
Welcome.

You may want to re-test both alloys. Something isn't right. A straight wheel weight alloy should test much higher than 8.5, more like 12 to 15.

According to my Lee tester, a 50/50 wheel weight/lead alloy is in the 9 range.

Tango2020
08-10-2011, 10:39 PM
Ill check again when I get home. (at work now) . The straight WW I only checked once but after adding 1% tin I check 4 times and they were all around 12 I know.

HeavyMetal
08-11-2011, 12:11 AM
If all he had was stick on WW then air cooled BHN of 8.5 is about right.

Tin will add some hardness but a 1% bump getting the alloy up 4 BHN seems a bit much unless he has a combonation of clip on and stick on weights then the tin will act as a magnifier and harden up any Antimony in the alloy.

Fit is good as long as the alloy is strong enough to take the pressure of the load you want to use. I'd think 12.5 would handle the average 40 load.

My closest loading manual says 6.1 of Unique to start with this boolit weight. I'll suggest you reconsider your start load as to light and move up the ladder a bit.

Next up is lube: I see your using the "magic" JPW and Alox Liquid lube. Never used this combo but I have used plenty of Liquid alox and hated it. I will not knock the lube but will suggest you get a tube of Carnuba Red and pan lube a batch of these .401 beauties to do a comparision with same load same alloy just lube change and see what happens.

Good luck

waksupi
08-11-2011, 12:27 AM
Age hardening?

MtGun44
08-11-2011, 12:31 AM
I agree with previous postings, 8.5 is too low for clip-on wwts and 12.5 after only 1% lead
is an unlikely increase - I hesitate to say impossible because I have not actually done that
exact thing and tested it. My wwt alloys run about 11-14 range typically. OTOH, I can
shoot 8 BHN in .357 mag with several designs using NRA 50-50 without leading.

TL for .40 cal is pushing the envelope, IMO. You may get it to work, more likely will not.

IMO, you would have a more direct and predictable path with a normal lube groove design
and NRA 50-50 to start. I understand the attaction of the low entry cost of Lee push
through dies and avoiding an expen$ive lubrisizer. Consider obtaining some sample
boolits from a member with a std lube groove and pan lubing and then running a few
dozen thru your Lee die to try. Have you verified that the Lee die produces .401 on
the output side? Are you using a micrometer that will read to 0.0001" or a dial caliper
which are typically good to +/- 0.001 or even 0.002"? If no mic, look at Fowler brand at
Enco tools online. They often have them for <$35.

Good luck and welcome.

Bill

Tango2020
08-11-2011, 12:55 AM
Thanks for the replies. There were stick on weights in with the clip ons but I'm starting to think my origional BHN measurement may have been off. I only measured once with straight WW when I came up with 8.5 plus it was my first time using the method. I am using calipers to measure so I may need to invest in a Micrometer for more precise measuring. Knowing that I was also getting leading with Missouri bullets I'm thinking fit may be my issue here.

462
08-11-2011, 10:31 AM
When melting wheel weights, segregate the clip-ons from the stick-ons, then segregate or mark the ingots as to their composition. Then in the future, mixing an alloy will be very simple, because you will have a known basis from which to start.

geargnasher
08-11-2011, 01:49 PM
Air-cooled clip-on wheel weights take a week or two to get near their final hardness. 8 bhn the day of casting doesn't surprise me a bit with mixed WW alloy.

Gear

Tag
08-11-2011, 02:22 PM
I cast for a Glock 23 with the Lee 175gr. with lube groove I use speed green or 60% bees wax/40% vasoline, I use HS-6 powder and keep it under 900fps. I don't claim to be a expert but this is what works for me. Hope this helps