How consistent are your 40-175 TC Lee casts?

[BJung]

I rushed casting 40-175 TC Lee bullets last night. Doing so led to me culling 1/2 of my casts because of wrinkles. Of those I kept, the bullets were weighed and all fell into 182-183gr and 185-186gr groups. This was the same as two previous castings. I tap my mold each time with a wooden mallet to assure alignment. Do any of you have this same experience in weight differences?

[dondiego]

Wrinkles are caused by the melt temp being too low, the mold temp being too low, or oil in the cavities, or a combination of all of these conditions.

[G W Wade]

Is this a 2 cavity mold. GW

[Harter66]

Every single Lee 6 cavity I have , there's 9 I think , cast 1 heavy , 2 light and 3 the same .

I've changed the way I pour , rested on the pot , rested on a hot plate poured fast/slow , 1,2,3,4,5,6 , 6,5,4,3,2,1 , 3,4,5,1,2,3 , 6,5,4,1,2,3 , like an inline 6 . It doesn't change if it's supposed to cast a 200 gr bullet it casts 1@196-198 ,3@205-6 and ,2@208-210 , the 158rf drops 1@158 , 3@161 , and 2@165 . The 40-175 drops 176,3@182, and 2@184 . I've paid $38-53 for brand new production Lee 6C moulds .

For 25 yd pistol non competition it probably doesn't matter . For more important things like hunting or competition it does but it's because it's important to keep them around 1/2" per 10yd and of course the carbine adds another layer of need to the equation.

If you NEED better than 1-2% weight control then you need to cast larger lots of spend for moulds with history of more consistency.

My 8c H&G #130 drops 8 bullets from 195.2-196.6 with most in 12# lots falling in 196.2-196.4 gr . The mould was $129 delivered with handles in 1992 .
My NOE 454-250 SWC version of the 454424 5C drops 250-251.2 . It's $125 now .

I sold the RCBS , Lyman , and LBT 2 cavity 40 cal 175 gr moulds because in applied feed , groups, speeds , and frontal area they didn't offer me anything in the 40 I wasn't getting with the 401-175 TLTC 6C and 3 times as many per pour .

[Bigslug]

Just to be systematic about it:

Dondiego's spot on - increase the heat and burn out any oil. Once you've got bullets with a frosty surface and good fillout. . .

. . .set yourself up a method for segregating bullets from each pour. Assuming you've got a six-cavity mold, maybe give yourself 6-12 pours that generate visually good bullets, set them aside, and carry on with the session. When you're done, weigh and sort them. That's going to tell you things:

1. If you have a significant variance in your cavities.
2. How many of your cavities differ in throw weight.
3. If that difference is measurable externally in terms of diameter or OAL.

FWIW, the only time I'll tap on a mold, it won't be on the mold, but on the handles where they connect, and it'll be to get sticky bullets to drop. I don't intimately know the Lee's but they all have alignment pins; do you have a reason not to trust them?

[fredj338]

My 6cav lee 40/175 is my best casting lee mold. I dont bother weighing pistol bullets unless they are for hunting loads. Most of my handgun shooting is def pistol training & idpa. Even 5gr diff in weight isnt affecting accuracy. I worry more about good bases.

[crandall crank]

I also have the same Lee 175 grain 6 cavity mold. Once up to temp, it runs well and very consistent. I do not weigh them, they are "close enough" to punch paper and ring steel plates. I powder coat them sometimes, but not always.

[Bigslug]

. . .And fredj338 has some additional good advice - the difference in your 182 to 186 grain variation range is only about 2% of your total bullet mass. This is only worth lying awake over if you and your gun are at the level of winning Bullseye matches, and there, you're likely applying equal scrutiny to your brass and powder charges.

If you REALLY want to go down a rabbit hole, sort and load your bullets by the extremes, then bench, chronograph, and group multiple ten-shot groups of each at a semi-challenging distance to see if there's anything worth getting applying that level of focus over. Unless you need better than minute-of-dog-food-can accuracy, there PROBABLY isn't, but such ventures do get one an education to move forward with.

[stubshaft]

Another 6 cavity user here and my boolits come out near perfect.

[JonB_in_Glencoe]

I rushed casting 40-175 TC Lee bullets last night. Doing so led to me culling 1/2 of my casts because of wrinkles. Of those I kept, the bullets were weighed and all fell into 182-183gr and 185-186gr groups. This was the same as two previous castings. I tap my mold each time with a wooden mallet to assure alignment. Do any of you have this same experience in weight differences?

First, I suspect you need to cast faster, so the mold is hotter.

With that helpful hint out of the way, I will say my Lee 6 cav 40-175 TC, casts excellent looking wrinkle-free boolits, I think this is one of Lee's better boolit designs, at least for casting functionality. I never tap a 6 cav Lee mold.

Now, as to 40 cal pistol boolits with "wrinkles" and a weight spread of 182 to 186gr ...THEY will shoot just fine at pistol shooting distances. Give them a quick tumble in BLL and load 'em up and take 'em to the range.

[Cast10]

6 cavity; 179-182

[Rp-]

I wish I bought that mold... but I was stupid. I didn't have a 40 or 10mm at the time so I o ly bought the 2 cavity mold. Now I own a 40 and a 10mm and use the hell out of that mold. I'll never buy another 2 cavity again!

Sent from my SM-G991U using Tapatalk

[pworley1]

After about 2 pours I almost never get a cull for the rest of the session. I will usually use two at a time once I get going. I will pour one while to sprue in cooling on the other. They are usually very consistent.

[dverna]

For blasting ammunition, I would not worry about your weight variation or the wrinkles. The wrinkles will cause you butt hurt....your "friends" will ridicule you.

I have lever action carbines in .38/.357 and would ditch a mold that had that much variation. Life is too short to deal with mediocrity when, for less than $100 more, you can purchase a high quality mold that will produce consistent bullets and allows you to also produce HP bullets if desired. Bear in mind an MP mold will last a life time of heavy use. No way I will sort pistol bullets.

Good advice about what is causing the wrinkles and you will have that solved next time you cast. I would be more concerned about you needing to hit the mold to insure alignment. Something seems wrong there.

[Dusty Bannister]

I may have missed it where the OP states it is with a 2 cav or 6 cav mold. If any mold is not aligning correctly when closing the mold, find and fix the issue, do not tap or bang on the mold to get it closed. Some find that laying the blocks on a firm clean surface will align the blocks before closing the mold. This can be when the blocks are unusually loose on the handles and allowed to flop around too much. With the 6 cav molds, failing to support the weight of the sprue plate while closing can create a misalignment and end up in damage to the mold corners which will then hold the mold blocks apart. Slapping the mold closed sharply can also raise divots around the female portion of the mold block.

A routine of hitting the mold blocks after closing, to settle the alignment pins into the holes suggests that there is a problem to fix which can resolve the weight variation issue. That said, it might be to your benefit to isolate several bullets by cavity for at least 5 casting cycles and determine by measuring and weighing if the problem can be isolated to a specific cavity or if it is casting technique.

Lastly, if this is the Lee 6 cav mold, DO NOT TOUCH THE SPRUE CUTTER HANDLE WHILE FILLING THE MOLD.

[Willie T]

I have that 6 cavity 401 175 TC mold. The mold I have is very good. I shoot a lot of them through a M&P40. Frankly I am stunned by the consistency of the bullets it drops and the boolits just fall out of the mold. I size to 401 and tumble lube them with 45/45/10 Alox/ Johnson’s Paste Wax/ Mineral Spirits. They are my go to .40 boolits.
Willie

PS-the most common causes for wrinkles in boolits I encounter when casting have been:
1. Mold not hot enough
2. Alloy not hot enough
3. Casting tempo too slow
4. Pour too fast
5. Alloy from sprue over running into an adjacent cavity

[rsrocket1]

The 401-175-TC is my most used mold also. Over 80,000 bullets cast with the mold. Once it gets up to temp, it does not need any heating or cooling. My TL452-240-TC needs to cool off a little between casts and my 356-120-TC needs a good warm up on the open coil hotplate (or about 10 casts) before it gets up to temp. You should really get the 6 cavity mold. With handgun rounds it's all about volume and consistency. Cranking 'em out at a high rate both adds to the volume and aids in consistency.

[GooseGestapo]

The molds are cut to throw weight using a roughly 92-5-2 alloy. (Lead,tin, antimony, trace arsenic).

You’re apparently using a soft lead, probably scrap. (I do too). I add wheel weights and Tin/antimony by adding lead-free solder (95/5). Also, I pre heat the molds by dipping the end of the mold in the lead until it no longer sticks to the mold. (20-30 seconds for 2-cavity, 60-90 seconds for 6-cavity Lee.) A NOE .314” 100gr mold took 2min due to extra mass.

Increasing the alloys also slightly increases as-cast diameter...
Preheat burns off oil/contaminants eliminating wrinkles.

[BJung]

I finished casting 40-175 TCs today. This time I worked from a table. Of the total, I culled 6 because the mold didn't close completely. Of the rest, they still were either 182/183gr or 185/185gr. I pulled out my ingots earmarked for 9-120 TC Lees. I bought this mold new and the bullets drop out when I open the molds. I could work much faster with these but haven't weighed the bullets yet.

[Larry Gibson]

I currently have 16 Lee 6 cavity moulds. They all cast excellent bullets w/o any wrinkles or variation in weight as mentioned.

I clean the moulds well when first obtained and do a bit of prep on them. My cleaning process is different and simpler than most methods recommended. When casting I keep the casting tempo correct to maintain proper mould temperature. I use a Lyman Mag20 bottom pour pot and keep the alloy temp between 710 and 725. I use two alloy thermometers to maintain that even temp.