Big .44 bullets are too big.

[Buck13]

I recently got an order of boolits from a small caster's business. When I took some of the .44s to the range today, I got a bit of surprise. The 429421s chambered and fired fine, but when I tried to step up to the big LBT 325 grain slugs, they would not chamber properly. With some stiff thumb pressure, I was able to get a couple chambered so I could latch the cylinder and barely get it to rotate.

The caster uses what I think is a fairly soft alloy: I can make a mark with a thumbnail that has some visible depth. I briefly considered trying to fire one, but decided that this sounded way too much like shooting a rifle with the bullet already into the rifling, which I know will raise the pressure seriously. Rather than find out just how tough a Redhawk may or may not be when confronted with 21.5 grains of H110 and a fat slug, I decided to wait and ask for adult supervision.




The photo is one of the chambered rounds. My best efforts with my cheap digital caliper show that the ring embossed by the throat is 0.432". Below that and the unchambered rounds all measure 0.433", while the 429421 and 429667 from the same caster measure 0.429 to 0.430", and can be pushed through the throats with only a couple pounds of pressure, so I figure my throats measure at least 0.430". At first I thought that, despite being lubed and gas-checked, the LBTs were not sized, but examining some unloaded bullets shows that the driving bands at and below the crimp groove are 0.430 and look more polished, so I guess only the ogive did not get sized? It looks like the sizing marks end halfway between the ring I made with the throat and the case mouth.

So, what to do? Shoot them like this? Buy a cheap Lee sizing die and touch them up myself? Write them off?

 

[rcmodel]

It looks as much to me in the photos as a bulge in the case from too much roll crimp.
Leading to the soft bullet being deformed / distorted / pushed off-center / bent during crimping.

Try some new bullets before seating, and see if they are too big to fit in the chamber throats without pushing them kicking & screaming through the chambers.

rc

 

[Buck13]

For a moment I thought you might be onto something, but they really do measure as I described. If I feed one base-first into the front of the cylinder, it goes in easily (maybe a little too easily) until the crimp groove has vanished, then it hangs up on what should be the base of the ogive, just below where the embossed ring is seen in the photo. There's roughly 0.2" of bullet that's too fat to fit easily through the throat. (That's a WAG. I wasn't trying to estimate that length when I was actually looking at it.)

Also, I seated then backed out the seating plug and crimped in a separate step, so the bullet wasn't being compressed by the crimping force. Any damage should be right at or inside the case mouth.

Maybe I should load these about 0.05" deeper so they chamber freely and just apply a light taper crimp above the actual crimp groove? They're not going to pull much under recoil, I guess.

 

[Buck13]

His tooling may do this to all excessively long bullets. I got a bag of 358627 boolits as well, and they measure 0.3585 below the upper crimp groove, but the first band above the crimp groove is 0.360".

Do lube-sizers not pass the bullets all the way through?

 

[rcmodel]

No.

Most push the bullet base first into the sizing / lube die with a ogive fitting nose punch.

Then the lube fills the grooves and it is pushed back out by the flat base center punch.

The nose section on the bullets would never see the inside of a typical lube & size die.

rc

 

[Buck13]

OK, that would seem to explain the situation.

So, choot 'em like this, or buy a Lee push-through die?

 

[Buck13]

The over-diameter part is a section around the base of the ogive, starting about 1/8" above the crimp groove. I just did a more careful examination, and it seems that the unsized section is about 1/16" long or maybe almost a tenth of an inch, not 0.2" as I guessed last night. In the first picture, you can see that about half of it is scuffed, then there is a little bit that didn't get pressed on the throat, then there's a line where the top of the sizing die stopped.

 

[mackg]

The problem with LEE push-through dies is their lack of accuracy.

Sometimes you think they use digital callipers and that, for example, .4519 is technically not .452; sometimes you just roll your eyes and shake your head...
Also as you mentioned, callipers are often not the most accurate tools to measure things with; so you'll have to deal with inaccuraties from both sides.

the dies I've had over the years measured as follow, from a good old fashionned vernier calliper:
.309: .311
.356: .3565
.357: .357
.428: .4285
.429: .429
.451: .452 (ordered specially for an old gun)
.451: .452 (This was a second order, mentioning the first one. It came with a note saying that a Tech had checked that die and found it to be .451)
.452: .4525
.457: .457

You will note that practically whenever my then inexperienced self could have used an oversized die, the one I received was dead on .

So say that you ordered a .431 die, you should be OK, allowing for dirty chambers and throats.
Unfortunately .431 would be a special order, and .430 should get you some leading; It could be honed to a bigger size matching your gun though. Just remember to match a dirty gun.

 

[TommyD45]

The LBT bullets have a wide front driving band and need to be slip fit for your cylinder throats. Size the bullet so that it slides all the way through with moderate thumb pressure. You don't want it to drop through freely, because the undersize bullet won't be accurate. Right now it seems too tight, and you cannot chamber your loaded round.

Ideally, you should get some push through soft lead sizing slugs and measure your bore and also your cylinder throats. If your cylinder throats are tighter than your bore, accuracy will suffer because the bullet is swaged down by the cylinder and will be undersize for the bore.

You can buy sizing slugs directly from LBT at this link: http://lbtmoulds.com/measurebore.shtml

 

[Miata Mike]

I have to ask, is the brass trimmed? A bit shorter brass to keep crimp in groove and shorter OAL.

I don't know off hand if Lee has a .431 push through, but I doubt it would take much to polish a .430 out or have Lee do it for you for a small price.

 

[Reinz]

No.

Most push the bullet base first into the sizing / lube die with a ogive fitting nose punch.

Then the lube fills the grooves and it is pushed back out by the flat base center punch.

The nose section on the bullets would never see the inside of a typical lube & size die.

rc

If this commercial caster uses a Magma Lube Master, the bullet enters the sizing die nose first, being pressed in with a punch at the base. The bullet IS pushed all the way through the sizing die, being lubed in the process.

Most commercial casters use this machine

 

[243winxb]

Bullets need to be sized correctly.

 

[Buck13]

If this commercial caster uses a Magma Lube Master, the bullet enters the sizing die nose first, being pressed in with a punch at the base. The bullet IS pushed all the way through the sizing die, being lubed in the process.

Most commercial casters use this machine

The details I wrote immediately preceding RC's comment you quoted should make it clear that these bullets never saw a push-through sizer.

Based on very little information, I believe this is a small operation making do with minimal tooling. I wish he offered sizing at 0.431". He sells some real cheap 429667, though.