Is a lead bullet swaged when seating in a cartridge - 32-20WCF

[StevenDJ]

I'd appreciate the input from some of the more experienced folk here.

I am casting and loading 32-20 or 32WCF (I'll add both names for the sake of the search function). I load with homemade blackpowder and a 20:1 (Lead : Pewter) alloy.

- Bullets are casting around 0.314 from an MP 640-314 mold
- Using the Lee resizing die brings the internal diameter to around 0.308 (a difficult measurement to make accurately with calipers) and the external neck diameter to 0.319
- I am using Starline brass which measures about 0.006 thickness (another difficult measurement to make) but this seems to coincide with the other measurements given the measurement error.
- After seating a bullet the external neck diameter is 0.326 so seating the 0.314 bullet is expanding the neck by 0.017.

This pressure required to seat the bullet makes it seam likely that the bullet would be swaged on seating.

I tried to confirm my own question by making the measurements, but although I am reporting measurements above, it is just as easy to report +/- 0.001" depending on where I make the measurement around the case neck and this means that the answer to my question ranges between 'everything being fine with some neck tension' through to 'the bullet must be swaged'.


Why take the time to slug the bore, obtain that data, find a bullet to match or potentially resize bullets only to swage the bullet further when seating it?

I'm unable to find any accuracy issues using the opensights on the rifle so this is more of an academic question.

Steve

[SiliconeSword]

Best move is to pull a bullet and measure it

[Bad Ass Wallace]

I think the leading edge of the boolit 'may' be swaged a tiny bit but 32/20 brass is very thin and easily expand to accomodate.

[StevenDJ]

Best move is to pull a bullet and measure it

Hey that was so simple I decided to do it. Bullets are 0.314 going in and 0.3135 coming out. I dont think ill loose any sleep over this.

Bad Ass Wallace, it looks like you are correct!

Thanks guys.

[mehavey]

brass is very thin and easily expand to accommodate.

don't think ill loose any sleep over this

Don'cha love it when a plan works out ?

[waksupi]

Size the neck as little as possible to cut down on swaging.

[Kraschenbirn]

OP doesn't state whether he's loading for a single-shot or a repeater but for my 32-20 Low Wall, I use an NOE expander plug to (re)open the sized case necks to .313 (+/-) to accomodate my Lyman 311008s loaded 'as-cast' (.314-.3145) then lightly taper crimp to remove any belling of the case mouth.

Bill

[SiliconeSword]

I'll add that when I started 9mm with a boolit with lots of grooves/little bearing surface and very sized brass I could pull a boolit and have it measure 10 thousandths under. What I eventually did was use a wooden rod, diamond paste, and a drill to lap out the carbide sizing ring in my die so it'd only have .0001 or so neck tension on a .3575 boolit. This made it only useable with cast as I have .354-.355 jacketed so I needed a second sizing die for jacketed but that wasn't a big deal.
Now even if you aren't getting boolit damage it still may be worthwhile to widen your sizing die as to reduce unnecessary sizing stress and make your brass last way longer.

[Bazoo]

My exeperience is that anything over .002 interference between the case's inside diameter and the bullet's outside diameter will result in swaged bases. It will only swage about 1/2 of the rear driving band if it's a tall band. Gas checks resist swaging and will expand the brass any amount. I've not tested 20:1, but I tested 50/50 WW/soft and it resisted .002 interference.

[StevenDJ]

Thanks for all the input everyone.

For the record, these reloads are running through my Savage Sporter 23C. I tidy little bolt action that is likely 100-80 years old.

Waksupi, I hear all the time that the neck can be resized or partially resized without the body. Does this just means that the cartridge is not fully sent home into the resizing die? How does one go about this process?

SiliconeSword, I was thinking similarly to this idea. It is not a carbide die, so it should be quite easy to achieve this. I was thinking of a similar technique that is used to lap a bullet mold. As you say, it won't be any good for jacketed bullets, but I don't plan on using g those when I can cast my own.

Bazoo, it seems I'm running around 0.11" interference. If I were to open the resizing die like Silicone sword has suggested, how far would you open the die?

I'd like to keep a reasonable amount of neck tension to keep a good powder burn characteristic.

Lastly, Mehavy, I like your cat! Looks like I feel most days.