recommendations on alloy

[jonp]

I recently acquired a SW 15-4 after reading the 75k thread and am going to start in on it. I am using a 145gr wc for now, Bens 60/40 lube and Promo. I am loading at 8-850fps. My question is on alloy. The thread has TFB using a 20:1 alloy, others suggested 30 or even 40:1.

Given the boolit, velocity and pressure plus its intended target use only what alloy would be best or will it matter?

[tazman]

In 38 special at those velocities, fit is more important than the alloy. Just make sure you have enough tin in the mix to get good fill out in your mold.
I tend to use harder alloy myself but it isn't necessary if your boolits fit the gun properly.

[btroj]

20-1 should work well. You could probably go to 30-1 without trouble if fit is right, Ben's lube is up to it.

Only one way to really know, isn't there?

[Love Life]

If you're are planning to use the revolver for target shooting, and not plinking, I would order up (or make up) a batch of the alloys listed and test them for accuracy.

If you just want to plink, then any alloy that fills the mould to the correct size will do the trick. If you haven't slugged the barrel yet, then .358 is a good size to start with.

All depends on the use you have planned for the gun.

[ShooterAZ]

Range scrap is what I use. Works great for this use.

[44man]

I will tell you what I would use, water dropped WW metal. You will find out shortly by yourself.

[bangerjim]

I cast ~10-12Bhn. Then powder coat it. PC'ing lets you shoot softer lead due to the protection it offers. No grease needed. No leading in the barrels. Lets you stretch your alloys.

Download the free alloy calc spreadsheet on here to calculate your mix easily.

banger

[Outpost75]

Factory soft swaged lead bullets are about 8-10 BHN, depending upon manufacturer. Typical backstop scrap or wheelweights is about 12 BHN, which will "work," but is harder than it needs to be in the .38 Special when loading at standard pressures, not exceeding 16kpsi. Factory wadcutter target loads seldom exceed 14kpsi.

The advice about getting small batches of known alloy and testing them for accuracy in your gun(s) is sound. I went through that process many years ago and determined that when loading .38 Special wadcutter for use in auto pistols, such as the Colt Gold Cup and S&W Model 52, that a somewhat harder alloy of 10 BHN gave tighter 50 yard grouping than the softer 8 BHN we then used in revolvers, but the difference was very slight, and only significant when firing more than 100 consecutive rounds from a machine rest and doing T-tests of a series of ten-shot groups from each gun.

If you cannot tell the difference, don't spend the money. Ordinary wheelweight alloy in a double-end, bevel-based bullet such as Saeco #348, loaded with 3.0-3.2 grains of current production Alliant Bullseye, in wadcutter brass with Federal 100 primers, properly assembled so as not to damage the bullet in seating and crimping, will produce sub-2-inch ten-shot groups at fifty yards from a good PPC target revolver or a heavy single-shot rifle fired off sandbags with a Unertl target scope. With harder alloy around 12 BHN you can increase the powder charge safely to 3.5 grains of Bullseye with excellent accuracy, producing a "full-charge" wadcutter which approximates the 850 fps of the old 158-grain LRN service ammunition. In .357 brass you can increase the charge to 4 grains of Bullseye for velocities which approximate .38 Special +P ammunition, but with target accuracy. Full charge wadcutters loaded in .357 brass will give better grouping than firing .38 Special ammunition in the .357 chamber, and will mitigate the chamber leading issue as well.

The very best factory wadcutter match ammunition back in the day would average 1-1/2" ten shot groups over a long series of 100 or more rounds, but ammunition of that quality is rare today and that level of accuracy is difficult to achieve with cast bullets, regardless of what people here will tell you.

130371130372

[dubber123]

I've fired enough sub 1" 25 yard groups with iron sights over the years from straight air cooled WW's to prove that is is a sufficient alloy for the .38 Spl. I can also tell you more accurate designs than the wadcutter exist. You might not notice at 25, but stretch it to 50 and beyond and you will.

[jonp]

I've fired enough sub 1" 25 yard groups with iron sights over the years from straight air cooled WW's to prove that is is a sufficient alloy for the .38 Spl. I can also tell you more accurate designs than the wadcutter exist. You might not notice at 25, but stretch it to 50 and beyond and you will.
Out of curiosity what designs do you find more accurate in a 38sp?

[41mag]

I won't even pretend to have shot as many DEWC's as some of these folks. Truth of the matter is, well other than about 6 months of shooting some of the Star HBWC's over some Red Dot, I only got to shooting the full DEWC's this past year.

To the alloy issue, well I got into this pouring up bullets to feed my 454 which is a far cry from a target loaded 38 SPL. Since then however I have really had a ball blending alloy and working with the MP hollow point molds in about 5 different calibers. What I have learned while doing this is that while you DO want things to match, as in alloy strength to pressures, the lower load levels of the 38 simply do not warrant anything extreme in the least. Straight COWW air cooled which comes out around a 14 BHN as well as some of my HP alloy which is only around a 10 BHN have both shot very well from my revolvers.

So I would give the basics a try first and foremost. If you have issues there, you might adjust your powder charge, or your size first, but if you already have alloy by all means give it a try. Picking up standardized alloy is expensive to start with and if you DO find you need it, then working with that calculator mentioned above you can pretty easily get really close if not duplicating it with what you already have.

Hope this helps.

[fredj338]

If you could get it to cast, pure lead would work, so my vote would go to 40-1 or if that won't shoot, try 30-1. As others have noted, range scrap would do as well.

[Love Life]

I like the swaged HBWC as well. Give those a try. I used to tumble lube them in LLA, but now use Ben's liquid Lube.

[truckjohn]

I would say that the bigger question I have for the OP is....

WHAT ALLOY CAN YOU GET?

It's fine to talk about 20:1 or 40:1 or whatever - but if all you can get is scrap wheel weights or range scrap lead - then you ought to start with that and see how it does.

I personally find it's pretty hard to FIND pure lead anymore without paying high prices.... So, I end up using what I can get and going from there... That means I start with range scrap or wheel weight - and then fiddle with tin or magnum shot to make it cast better or harden a little more or whatever...

Now, if you have something too hard - you can soften it by heating it as hot as you can and stirring it for HOURS - to oxidize out the alloying elements (Tin, Arsenic, Antimony)... That's a royal PITA, though...

Thanks

[jonp]

I have pure Pb, COWW, SOWW, Range Lead, Isotope and some Pewter to mix in. I can make most of what I need and I shoot into my own trap in the backyard so recovery is 100%. Once I dial it in I can recycle the lead pretty much forever

[Lloyd Smale]

there you go. Yes you could probably get by with even pure lead at those velocitys but if you want the absolute best accuracy that 15 will show you then harder will almost allways be better.
I will tell you what I would use, water dropped WW metal. You will find out shortly by yourself.