Questions about. 357 mag reloading data

[Walkalong]

I would bet on it, and it would be easy to test that theory.

Check the size of the revolver throats if you can. They might be undersized, or oversized.

 

[Mixed Nuts]

Walkalong, undersized or oversized compared to the bore? The only way I've got for checking that would be my calipers, the inside to inside part of the tool. I'll try it, but it may not be too accurate.

 

[someguy2800]

See if you can push a bullet through the cylinder throat. Either way a hotter load may be all that's required.

 

[someguy2800]

My sp101 leaded bad with 158 hard cast in 38 special until I opened up the throats slightly and switched to 700x to get the pressure up faster. I since switched to plated 125's and I like that better. I shoot jacketed in 357 since that's my hunting load, so my experience with cast in a revolver is only 1500 rounds of 38 special and a few hundred 357's.

 

[Walkalong]

Walkalong, undersized or oversized compared to the bore?

Throats need to be over groove diameter. .001 is about perfect. If they are under, it will lead, no matter what. Since you have lead in the throats, the bullet is likely undersized for the throats. Bullets need to fit the throats. If the throats are over sized, and the bullets hard, and the pressure low, it's lead city.

Yep, hard to get a good ID with calipers. Pin gauges or a good inside micrometer are best.

Do as someguy2800 suggested, see if you can push the bullets through the throats. If they are a tight slip fit they are good as far as the throats go. If they rattle around, not so much. If they won't go through the throats, the throats are likely undersized for the groove diameter.

A softer bullet should work for both loads, or you could just go coated. Or use those bullets for full power and get some plated for midrange/soft stuff.

 

[Mixed Nuts]

Someguy2800, so, I think I get it. The hard bullet, if it's too small, won't expand fast enough with a low power charge of a fast burning powder. A full power charge, qith a slower burning powder widens the base enough before the burning gasses can slip past the bullet? Is this it?

So, if I didn't lead with decent charges of accurate 9, and if I've got lead in the cylinders, then what's our first diagnosis? Wide throats, right?

Walkalong, gonna try this, sir. Appreciate your involved assessments.

 

[Walkalong]

The hard bullet, if it's too small, won't expand fast enough

No

The higher pressure of the full power load bumps up the base of the bullet to seal the throat and then the grooves, stopping gas cutting. The lower power load does not.

With the midrange load less of the faster powder is still making less pressure than the full load with the slower powder. It isn't enough pressure to bump up the bullet, leaving a (tiny) gap, where hot gas leaks by at high velocity, causing gas cutting of the lead, just like a cutting torch.

 

[Mixed Nuts]

Well gentlemen, I just tried to fit a bullet through the cylinder and it would not go through.

Then I tried to fit it into the forcing cone, it started in but, before it was halfway out of view it stopped there, too.

In the cylinder I used a pencil, un-sharpened, to push the 158grain SWC but when the bullet got near the front end of the cylinder it stopped. Even with some force I could not get the bullet as far as the face of the cylinder.

Dang it.

 

[Walkalong]

https://www.google.com/search?q=cylinder+throat+reamimg&ie=utf-8&oe=utf-8

 

[Dudedog]

sorry got the bullet type wrong I thought I saw Oregon Trail someplace. (senior moment)

 

[Mixed Nuts]

So what's our current theory? Cylinder throats too small, slightly smaller than bore?

Bullet is being sized down to slightly smaller than bore size, allowing for gas cutting after bullet enters bore?

This seems to pose questions, no?

Why no leading with accurate no9?

Maybe I missed it... I don't think so...

Why leading in the cylinder chambers?

After further inspection, I found lead on the face of the cylinder and at the inside front bottom of the frame cutout for the cylinder. Like it splashed there...

Could I have gotten a few bad bullets? Dunno, although once the carbon was mostly off the lead came out of the barrel shiny, like hard cast. Although was darker on frame and cylinder face. Weird.

I guess if i want to proceed with cast lead - and I've ordered 2 lyman molds - I'll need to slug the bore and measure the cylinder throats.

I may shoot jacketed ammo for a bit, until I figure out how invested I want to get.

 

[Mixed Nuts]

I'm gonna slug the barrel and measure the throats, too.

I like accuracy, and I want to shoot lead. If i spend a little money and time, I'll be able to tune other revolvers in future.

And it looks like, slugging a revolver barrel means pounding a soft slug all the way down the barrel as there's no way to back it out.

Would a swaged frontier .358 from hornady work for slugging? I saw thoes in a nearby shop.

And a pin guage or inside micrometer, too.

And maybe a brownells cylinder throat reamer.

My .357 trip is turning into quite a saga.

 

[Walkalong]

You can buy individual pin gauges. No need for a whole set just to do these throats.A soft lead bullet is perfect for slugging the bore. Have a fishing weight the right size?

 

[Blue68f100]

You want to use pure lead if all possible. It's a lot softer than any alloy. Like mentioned fishing weights are a good source. but some are now zinc. I take a piece of fired brass and melt lead into it. With it's shape it's coned shaped and only will be a few 1/1000's over the size your looking for. The cone shape make it easy to start. DON'T use wood to drive it through though, brass rod is preferred. Wood can splenter and get wedge in place.

 

[someguy2800]

There are people a lot more knowledgable than me with shooting lead in a revolver but here is my experience. When I got my 4.2" sp101 the first bullet I tried were 158's from SNS that I can get locally which are 18 BH. My goal for a load was a real soft shooting plinker, so like 700- 800 fps in 38 special. I shot some left over AA5 (which I hate) and some HS6 and it leaded severely. With the same bullets loaded in 357 magnum cases with a stout charge of AA7 (also hate that powder) it did not lead and would actually remove the leading from shooting the 38's.

A .357 bullet could be pushed through the throats with some force, but a .358 could not. I honed the throats out carefully with some equipment I had on hand until a .358 bullet would slide through with a few ounces of force. This cut the leading considerably but still had to clean it out after 100 rounds. Then I called SNS for advice and they suggested a faster powder to get the pressure up faster. I got some 700x and after that had no leading at all even shooting a bullet that really is too hard for the velocity.

So you may be able to fix the leading by opening up the throats to be able to shoot light loads of unique or other loads and maybe a softer bullet to seal the bore faster

If you don't want to modify the gun just try shooting the other powders you have some more. The pressure curves may be different enough to get the bullet to seal even with the undersized throats, which it seams was the case with AA9.

I shot 4 boxes of 500 of the SNS bullets in mine but found I didn't really care for lead in that gun. I'm lazy and I don't like to clean guns. I didn't like how filthy the gun got from the burning lube and also found that 158's in 38 special resulted in a radically different point of impact than my 357 jacketed loads I wanted for hunting. After some experimenting I found that 125 grain Berrys plated were actually cheaper than what I was paying for 158 cast, and I was able to get the same point of impact with a 140 grain XTP with a full house load of H110. Having two loads for the same gun with dramatically different power factors but the same point of impact really makes it a much more useful gun to me. I hunt small game and plink with the 125 grain berries FP at 800 fps, and hunt deer and make fireballs with the 357 with xtp's. I also recently found that a 125 xtp loaded just right is only about an inch different at 25 yards and I get a good deal more energy with the 125 vs 140, so that is the new 357 load. And I hardly have to clean it anymore except wiping down the outside. I do greatly enjoy shooting cast in 3 of my other guns though.

 

[Mixed Nuts]

Walkalong, do you reccomend using the regular calipers for measuring the slug hammered through the barrel? And the slug is measured at the widest parts, yes? Where the slug has gone down into the rifling grooves. This widest measurement is the bore diameter?

Blue68f100, I'll remember that - about not using a dowell. As for making a slug. Not in a position to do that yet but I'll add your method to my notes.

Someguy2800, interesting story. I think my problem may be a lot like yours was. And yeah, the lead does make a mess. I came off the shooting line with black soot on both hands. And I drew polite, but likely negative questions from the range staff. I'm done shooting lead indoors. Although, I want to be able cast if I need to.

I've read a few short article on reaming the cylinder throats. Is said to improve accuracy. I was looking at a cylinder reaming tool on the brownells site and it was sold (if memory serves) with a .354 pilot. A pilot pack was offered with it, pilots from .354 through to .359 or so. I was wondering if those pilots could serve as pin gauges? If they could I'd buy them and get set up with a one stop shop.

 

[Walkalong]

Walkalong, do you reccomend using the regular calipers for measuring the slug hammered through the barrel? And the slug is measured at the widest parts, yes? Where the slug has gone down into the rifling grooves. This widest measurement is the bore diameter?

Yes, and correct, groove diameter for the barrel.

Reaming throats doesn't look overly hard, but there are also folks who do it for a living that you can send the cylinder to.

A pilot pack was offered with it, pilots from .354 through to .359 or so. I was wondering if those pilots could serve as pin gauges?

Well, I guess you could measure them with a micrometer and use them to check the throats. You would have to keep them square when doing it.

 

[Dudedog]

Side note: If you shoot indoors a lot I would suggest getting your lead levels checked. Mine were really high at one point in time and I traced it to the indoor range.
If you have it, insurance will usually cover it. Tell your Dr you shoot indoors and have heard it should be checked.
I don't know how much it is if you don't have insurance.
Levels can be high and you might not have any symptoms. Symptoms vary. Google lead poisoning.
If is was shooting indoors I would shoot plated or jacketed. Still have lead from the primers, and you can't control what other people are shooting, but to much lead in your system is no joke.

 

[Buck13]

Does Trail Boss play nice with these coated bullets?

 

[Mixed Nuts]

So, with regard to leading with the hard Cast Performance brand bullets I was using. My notes say the bullets were labeled 18 BHN. Well, I got a Saeco bullet hardness tester yesterday and I just checked the subject hard bullets that lead at low speed and don't shoot tight at any speed out of my 6" Security Six.

Saeco says - 26 BHN for these bullets.

After searching the remains of the original packaging I can find no hardness numbers from Cast Performance. Maybe I threw out a paper insert from the box? I dunno. But what remains of the label calls the bullets "heat treated solids." Well, they're pretty solid. They will be melted and mixed into something softer... and, as a newbie caster, I'm feeling more optimistic about cast bullets in general.

 

[Dudedog]

BHN 26

Mixed Nuts,
what have you decided you like for powders?
Did you get better results with different bullets?

 

[Dudedog]

I don't cast but this is an interesting read.

https://www.thehighroad.org/index.php?resources/cast-bullets.4/

 

[Mixed Nuts]

BHN 26

Mixed Nuts,
what have you decided you like for powders?
Did you get better results with different bullets?

A couple days after that hardness test I tested again. This time on multiple bullets from the same boxes - have 2 boxes. All new tests came in at SAECO 10 which is 22 BHN. So the bullets are not 26 BHN - although one was just under SAECO 11 which would be about 26.

I didn't try new bullets. Instead I began to buy casting equipment. Currently have two 4 cav Lyman molds - the 358665 and the 358429 with handles. Have a Lyman ladle and a Lee electric pot.

Bought the Manson .358 throat reamer with a full set of pilots for the Ruger with an under-size cylinder throat or three. Bought a cheap micrometer. Made some powder dippers for a series of 2400 loads. Bought the SAECO hardness tester. And have a couple of .35 Remingtion cases that I'm going to make into cake cutters for pan lubed .358s.

Of course I still have Accurate No.9, W296, 2400, IMR 4227, and Unique. Although I may never us the Unique as it seems weird to me putting so little powder into the cases, the loads were wimpy, and they leaded (although I should be fixing that).

I must say that I've felt one step behind during this equipment procurement. If I did it again, knowing I was going to get the Manson reamer and knowing what I would learn on The High Road, books etc... I'd have bought custom molds at .359 or .360. As of now, I'm worried about the Lyman's dropping smaller than or at .358. There is a guy online who enlarges the driving bands of Iron molds so I may go that way if the castings are small.

Anyway, after all that, I still haven't cast. It's too hot here right now. Have collected some brass from shooting factory Federals. In a month or maybe two, I'll get casting, get the molds how I want them, and conduct the tests again with the above powders, give or take Unique which I'm not too excited about anyway.

That's where my grand experiment is at.