Author Topic: Need Help: Severe Leading In Model 686 (Read 783 times)

J.Solo · « **on:** June 27, 2004, 04:23:50 AM »

I have a S&W 4" Model 686, .357 Magnum and I'm shooting 158 grain SWC Hard Cast Lubricated Lead bullets from NBC Bullets out of Ohio. I'm experiencing severe leading at the front of cylinder, forcing cone and completely down the barrel. I'm using 6 grains of Unique as a load at about 1000 fps.

NBC Bullets measure .3590" dia.
All cylinder end holes measure .3575" dia.
Barrel Measures .3560" dia.

I have 2000 of these NBC bullets and would like to save them.

I also have a Lyman #450 Lubresizer press and I was thinking of getting a SWC Top Punch Die and a Sizing Die to resize all the bullets and all brands of future lead bullets. But I don't know what dimension to size to.

I don't know what Part Number and dimension of Sizing Die and Top Punch to buy. Based on the gun and bullet dimensions I have found, can anyone suggest what sizing die and Top Punch I should look for? Does anyone have a set up they would like to sell?

Thanks - J.Solo

Leftoverdj · « **Reply #1 on:** June 27, 2004, 07:19:46 AM »

Before you go doing anything drastic, just put a coat of Liquid Alox on about 100 of those bullets and try them that way. Could be a lube problem.

Could also be that those bullets are too hard for your mid-range load. Try some in a full house load and see if that works. Real hard cast bullets are all the rage, but the truth is that you are a lot better off with a medium soft bullet in the 800-1000 fps range.

.359 should work just fine. It's undersized bullets that give trouble, not the ones that are just a couple of thous oversized.

J.Solo · « **Reply #2 on:** June 27, 2004, 11:19:51 AM »

I've posted this question on Graybeards, RUGER and S&W Forums. Most responses I'm getting say to decrease the load and size to .357-.378. I'll call Lyman tomorrow and explain the problem and see what size, sizing die and top punch would be correct. Anyone with a set up to sell please let me know before I order anything. Thanks - J.Solo

Orygun Mark · « **Reply #3 on:** June 27, 2004, 01:31:43 PM »

J.Solo,
Listen to leftoverdj. It could easily be a lube thing like too hard of lube. I use ww's for up to 1400 FPS and add 1% tin or so and use gas check bullets above that. .359 should be sized OK If you size them .357 or .358 I would expect to see more leading. I might try a different powder or go down 1 gr and up one gr to see if conditions change. I have use commercial hard cast that leaded badly until I changed the lube to a softer lube. Mark

Lloyd Smale · « **Reply #4 on:** June 27, 2004, 01:34:45 PM »

I agree with the lube idea. Most of the comerical bullets use a lube so hard that its useless. Try to recover a bullet out of the dirt and i be most of the lube is still on the bullet.

J.Solo · « **Reply #5 on:** June 27, 2004, 02:44:01 PM »

You guys are most likely right about the lube but the bullets are already lubed. To remove the lube and re-lube would be more work than the bullets are worth.

By the way my original measurement of the barrel was .356". I slugged the barrel and is came up .3555 when measured with a set of digital calipers. - J.Solo

Nobade · « **Reply #6 on:** June 27, 2004, 03:07:06 PM »

I agree with the tumble lube suggestion. I can often salvage factory made cast bullets with a coat of Lee liquid Alox. Most of the time I either boil them to remove the factory useless lube and apply 50-50 or if nothing works I'll melt them down to make rifle bullets. Loads as light as you're using need much softer bullets.

Leftoverdj · « **Reply #7 on:** June 27, 2004, 07:03:19 PM »

Quote from: J.Solo

You guys are most likely right about the lube but the bullets are already lubed. To remove the lube and re-lube would be more work than the bullets are worth.

By the way my original measurement of the barrel was .356". I slugged the barrel and is came up .3555 when measured with a set of digital calipers. - J.Solo

Who said you had to remove the lube? Just tumble lube them as they are.

And if I wanted to remove the lube, I would not go to any more work than dumping the bullets into a pot of boiling water.

Castaway · « **Reply #8 on:** June 28, 2004, 12:47:52 AM »

Read your original post and thought maybe the pressure was too low for a hard bullet, then I thought I'd get a bottle of Lee Liquid Alox and tumble the bullets in that. Getting excited about offering some original advice, I scrolled down to Leftoverdj's post and low and behold, he beat me to it. There's been a lot of publicity about hard cast bullets. Most bullet manufacturers advertise that way. This has convinced many new lead shooters to believe that's the way to go and they get into trouble with excessive leading. The secret is that it's easier and faster to produce hard bullets with fewer culls. To complicate the problem they cast with a bevel base. Then they advertise that the bevel base is easier to seat.

J.Solo · « **Reply #9 on:** June 28, 2004, 06:03:23 AM »

I went on the NBC (National Bullet) Web Site and found that the 158 grain bullet I'm using has a Brinell Hardness of 18 (7% Antimony and 2% Tin mixture).

I also talked with a Lyman Rep. who confirred with their bulleticians and the most critical dimension I gave them were the cylinder exit holes of .3575".

Based on that they recomended a Sizing Die of .358. They said it was important that the bullet does not "rattle around" when leaving the cylinder and entering the barrel's forcing cone. the .0005" touch was enough to accomplish this.

I'm working with Lyman right now as to what Top Punch would fit the NBC bullets. Lyman's Top Punches are made for thier Molds so we have to find the best fit of Top Punch to NBC bullet.

I appreciate all the information so far. I've received a combinztion of information from all the Boards I've posted on that say:
Increase the FPS & decrease the FPS with the same powder, switch to a slower powder, try a different Lube, Lube should not effect it that much, size the bullet diameter down, leave the bullet diameter at .359".

My plan is to:
1. Re-size the bullets to .3580"
2. Use less Unique powder for lower FPS
3. Use more Unique powder for higher FPS
4. Try a slower powder.
5. Try VtVorhe (spelling) #110

Thanks for all the information to date. Keep it coming if anyone has anything else to share. - J.Solo

Castaway · « **Reply #10 on:** June 28, 2004, 07:55:20 AM »

As a side note. It's cheaper to buy a bottle of Alox and add more powder and test drive the combination before you go the route of buying a resizing die. In my experience, bigger is better when loading cast bullets. You can safely go 0.002" over and still be safe. Lead is "slick" compared to jacketed bullets and it seals the loose spaces that can cause leading. With a BH of 18, you need about 26,000 PSI pressure to obturate the bullet. Without looking at a book, I suspect you are way below that pressure. I'd add enough powder to get the pressure up there and see what the news is (after I aloxed). Good luck.

J.Solo · « **Reply #11 on:** June 28, 2004, 07:42:53 PM »

Castaway:

So where do I get some Liquid Alox?

Please tell me I can get it at a Hardware or Auto Parts Store.

Thanks - J.Solo

warf73 · « **Reply #12 on:** June 28, 2004, 09:20:57 PM »

J. Solo

I had same problem with my 44mag bought some of them hard bullets with the hard lube.
Leaded the living sh*t out of my barrel.
I did recover a bullet.
ALL the lube was still on the bullet.
That was my problem so I got a pot (my big lead melting pot) boiled up some water to get lube off. Then lubed them all with my lube.

Haven't had any leading problems since.
And they were about .0025 bigger than bore dia.

I now pour my own bullets with WW.
My load is a 255gr. SWC running 690fps out of a 4" barrel.

Good luck hopes this helps.

Leftoverdj · « **Reply #13 on:** June 28, 2004, 10:05:52 PM »

Any decent gun store will have Liquid Alox. Even the little gun shops will order you a bottle or two. and have it in a few days. Any of the mail order places like Midway or MidSouth will have it. Bottle should be about $3.

J.Solo · « **Reply #14 on:** June 29, 2004, 04:43:59 AM »

I finally found my 1973 Lyman Cast Bullet Handbook and compared it to the information I have been using in the SPEER #13 Reloading Book.

The SPEER Manual lists 6 grains of Unique as the Max load = 1034 fps.

The Lyman Manual lists 8 grains of Unique as a Max load = 1400 fps.

I'm thinking that most Manufacture's loading manuals address their own, soft to semi hard lead bullets in their loading manuals while the Lyman manual addresses Hard Cast Lead bullets for their loads.

Without further experimenting it looks as though I've been loading Hard Lead Cast Bullets to Soft Lead Cast Bullet charges. This may be causing the leading I'm having, as the Hard Cast Bullet is moving too slow with the current powder charge.

My next step is to load the NBC bullets to 7.8-7.9 grains of unique and see if the leading stops.

J.Solo

Castaway · « **Reply #15 on:** June 29, 2004, 06:24:27 AM »

As stated above, you can get Alox at most gunshops that carry reloading supplies. If not, Midway at midwayusa.com can ship you out some pretty quick. Jacketed data tends to use lower powder charges than cast bullets, but that's not always the case. The same weight lead bullet, if it has a greater bearing surface may take less powder to stay under the pressure allowances. If you contact Midway ask about the "One Caliber" loadbook series in 357. A wealth of information.