Ooopsy

[PWS]

Just for curiosity, does anyone have a good guesstimate of what PSI would take to crack this home made sizer die?



I was trying to swage a .45acp case down to .412" OD for a jacket and made the inside punch to big. It just started to come through and POP!

Material is 1144 Stressproof, inside diameter of .412", outside diameter of .960", length of cylinder 1.400". From what I gather, the 1144 Stressproof has an ultimate tensile strength of 115kpsi so it would take ~43klbs to pull apart the ~.37in2 sidewall. Not sure what that all means in terms of hoop strength, pressures etc.

I'm just getting into swaging as I put together and .400Whelen and have way more time than money right now. Got some O1 on the way to make more dies.

[wonderwolf]

Wow, what press were you using and did you have a cheater bar on that?

[xman777]

Holy Moley. I'm guessing you gave that a lot of Moxey.

[Cane_man]

they aren't hard to break like that if not annealed properly, don't ask me how I know

[PWS]

I didn't heat treat the die so perhaps it would have stood up at a harder state. The die really was made more for presizing .412" cast boolits with thick .416 gas checks. Got a crazy notion late last night and crammed a .45ACP case through up-side-down hoping to come up with a possible swaging jacket. Gave 'er a good shove and POP! That was that.

I have seasonal access to a pretty good shop so I built a press in my spare time. It's basically an overbuilt reloading press with a short toggle pivot. I'd love to know what kind of pressure it took to pop the die as the press handled it fine. My first thought on hearing the snap was, "****! There goes 120hrs of shop time on this stupd press!" Luckily, it was just a three hour die.

The jacket is for a .400 Whelen bullet. Just put one together and have been struggling with components. 40S&W and 10mm brass are about right diameter but the 40's a bit small and the 10's a bit scarce. Lots of 45's to be had though.

I've studied your threads, CaneMan, and really appreciate you posting your trials and tribulations and especially your triumphs. Hope to emulate your die making and using success eventually.

[aaronraad]

Plugged the numbers into Corbin's dc-dies program and got this -



Never really used the program myself so not entirely sure about the outputs. Maybe someone on here has done the engineering calculations to back up what the program spits out?

I guess there is always some level of jacket wall thinning when re-sizing/re-drawing, but I wouldn't doubt that pressures sky-rocket when ironing the jacket walls.

A question maybe worth asking is your punch shape, surface finish, lubrication correct, not just "too big" a punch as a contributor to pressure. By that I mean, what was the condition of the case after you extracted it from the cracked die? For instance, did the case head separate from the case walls and is the outside of the case badly scored etc.? Is the punch still straight, e.g. was there an alignment issue giving the impression the punch was oversized?

Not saying you haven't already asked yourself these questions, but I for one would certainly appreciate any learnings with a few more pics and any failure investigation findings you come up with!

PS: Have you posted anything previously regarding your press toggle modification you also mentioned, just out of interest?

[FrankG]

I don't swage Yet ................but .470" to .412" in one fail swoop is a big squish all at once . I bet in 3 or 4 steps it would be doable with annealed brass .

[runfiverun]

Actually a rock chucker press has enough oomph to break a swage die.
Brittleness of the dies steel makes it easier, you need a Rockwell hardness on the surface to resist wear but the die body itself needs some give inside it.
Think bolt action rifle reciever.

[blaser.306]

I don't swage Yet ................but .470" to .412" in one fail swoop is a big squish all at once . I bet in 3 or 4 steps it would be doable with annealed brass .

I just finished making my first draw die and I went from .390"-.358" in a single draw on a Corbin CSP-1 and it was a fair pull as well so I can imagine what the internal PSI might have been. As mentioned think rifle chamber! With the exception in a die it is a maintained pressure not only for a micro second!

[Southron]

WELCOME TO THE CLUB!!!!

I have had three swaging dies crack on me. When the last one failed, it sounded like a 30-30 rifle going off! I found fragments of the die all over the shop, fortunately no fragments hit me. It could have been worse, I could have permanently bent my cheater bar!

When you are swaging, you are putting a lot of PSI in that die. Just think of firing a 30-06 with a "Hot" handload and you get the picture.

Keep in mind that your swaging dies have to be heat treated perfectly or sooner or later, they are going to crack on you.

[MOcaster]

PWS, could you post a picture of your press for us? I know I'd love to see it and I bet some others would too.

[owejia]

We used to use the stressproof steel for shafting, about 25 years ago. It handled the twist of the impact of turning really well, things like hammer mills and tire drum machines, machines really good also. Never tried that kind of expansion pressure on the stressproof metal. We used o1 or A2 for those applications.

[Cane_man]

lesson learned... it is worth it to take the extra hour after heat treating to anneal in your kitchen oven at 350F

no big deal to draw down a 9mm case from .390 to 0.354 in one pass using a 2 ton arbor press draw by hand... I can take it from 0.390 down to 0.280 in 6 draw downs, with anneal after every 2 draws... do this to make cases for 7mm 135gr

[Geppetto]

Don't use 1144 for that pressure application. 1144 has aligned manganese sulfide inclusions that make it really nice to machine. The inclusions are aligned in the longitudinal direction (length) of the bar. The result, however, is that the material has poor ductility in that orientation. I have seen tons of failed components with radial cracks when produced from 1144. Do yourself a favor and use a different material for the new one. Any steel that is not a 11xx or 12xx series should work fine for you. Use a 1040 or 1045 if you are going to heat treat it. Pre-hard 4140 or an appropriately sized grade 8 bolt will get you some hardened material to work with. They are all going to be a little more difficult to machine in comparison, but they aren't going to break radially from internal pressure.

[PWS]

Thank you everyone for all the great info!

I used the 1144 only because that's what I had on hand and actually made another die with it yesterday. With the proper punch, it's reducing annealed .45ACPs to .412" in one stroke. The successful punch has a .400" long taper from .380" to .280" on the nose. The other punch only had a small radius at the nose and bound up in the web of the case. In the first pic, the ring with the crack is the die and the narrow darker ring is the case so you can see how tight the case was around the punch. The case was starting to protrude from the die so I faced everything off and center drilled the punch for a pilot and thought, hmmm, that looks like a good topic started so took a quick pic before drilling out the punch.

The press head is bored and threaded for 1 1/2x10tpi so the cracked die was only bound in the adapter. Drilled out the punch, spun out the cracked die and back at it. Being able to removed the adapter sure made the fix easier than dealing with a die stuck in the top plate.

I've got some O1 coming for dies and reamers plus some 1144 for punches. If this second die pops, I'll make another out of O1.



This is the press. The handle is 18" long and the toggle pivot length is 1.75". It's not much of a multiplier until the toggle swings under the ram, then the ratio sure goes up!

[aaronraad]

Hi PWS, no luck with linking to the attachment for me anyway.

Thanks for the punch description!

[Cane_man]

didn't read carefully that it was 1144... stress proof is great for punches as its compressive strength is almost 3X that of O1... I think O1 is awesome for the home machinist to make swage dies as it turns fairly well and it can easily be heat treated at home... heat to orange then quench in oil, anneal in kitchen oven at 350F for 1 hour... McMaster has a great selection of O1, decent pricing, and their service is awesome...

never got to try O6, but I understand it machines better than O1 and can be heat treated in a similar manner

[jimbull34]

PWS, I was wondering what you used for a punch? Did you turn one or was it a drill blank? I have broken 1144 steel that I had on my hydraulic press by a punch that hit off center and I was not paying attention to what I was doing, one beer too many thing I believe!!!! Anyway it may be you punch was out of round...also, I know a lot of people here don't use 12L14 for dies, but I do and have had excellent results using it. It mills/turns great and holds up super good. I for one, am not a believer in the theory that steel wears out, deforms and stretches when brass is pushed thru it. I have worked with some very different steels (gov't jobs) and have found over the years that common sense prevails in most applications, meaning the softer metal is the only one that changes...just my .02 cents

[PWS]

Jimbull,

I had to drill out the punch so I don't know if it got deformed but doubt it was out of round. It was a grade 5 bolt and the thin tube that remains after boring is pretty even on the circumference. I think the root cause was that there just wasn't enough room for the case wall and punch nose within the die hole without the case extruding significantly lengthwise and the die split because the punch wedged it apart. I was really reefing on the handle at the end of the stroke - gain a little, screw the die down further, gain a little, repeat... POP!