.355 105 SWC Sizing and COAL

[kenn]

I've got a Walther I'm trying to use this little boolit in. Cast, these are coming in right around .360 and I'm sizing down with a Lee .357 sizer which leaves them at .3575 according to my micrometer. I slugged by barrel and I can't get a consistent read but I *think* my barrel was slugging at .356. With .3575, the bullet will not chamber completely unless I seat it way down to barely showing the top band. This makes the OAL about .997. The recipes I can find and suggestions on this are to seat to the top of the crimp groove leaving the overall length at 1.03.

It seems, like my 1911, the PPQ headspaces on the brass and has very tight tolerances. This seems to be similar to what I've found about walther guns online in general -- i.e. very sensitive to OAL on a sharp shoulder round vs. a ball round.

Is this thing going to be OK with an OAL under an inch? I believe the formula is going to have to be .996-.998 (variations in the equipment with a .997 goal. Given the "suggested" on a similar bullet is 1.03, that's not that big of a change, really, and I'll adjust powder down slightly and will probably start at about 3.6gr of Bullseye seated that deep and work up.

Suggestions?

[Bonz]

Are you talking about a 9mm or 380 ? That seems like a lot of Bullseye powder for that load. what is the length of that boolit (projectile) ? Just out of curiosity, gonna pump the data into Quickload. I would love to try a SWC in my .380's

[kenn]

Bonz, I'm loading for 9MM. I'll send you some in the mail if you'll PM me your address and thanks for the offer to look it up in quickload. Do you have a sizer? They cast about .360 with an occasional outlier at .362 when I'm not holding the mold tight. I *think* the bullet drops at about .531 in length, but I'll need to measure when I get home for certain. Sizing the diameter down from .360 to .357 elongates it ever so slightly so I'll measure both and post up the data tonight. If you don't have a sizer, I can size to .3575 as that's all I have...

[Bonz]

QuickLoad does not like that bullet length. I'm assuming it is a Lee 358-105-SWC which has a length of 0.510 only. We need to wait for you to re-measure when you get home.

[Beerd]

I size to .357" and seat to 1.000" for my 9mm FEG "Hi Power".
OAL measured with vernier calipers so plus or minus .003" is plenty good in my book.

Can't comment on the Bullseye load. I mostly use Unique.
..

[Rattlesnake Charlie]

Loading in .380 ACP
I load this bullet sized at .358 to a length that has about one-half of the top band showing. I like 1.3 gr of Red Dot. Works fine in my FEG Walther PP clone. 2" groups at 25 yds.

[kenn]

Bonz, I measured up 10 and got .5065 as my average length for this little bullet.

I made 10 dummy rounds playing with OAL until it would JUST drop in and not get the band stuck in the throat and allow me to pull it back out again. That length, as determined by my gun is a VERY short .955 to .960. The soft nose gives a little when setting the bullet with the lee punch in the bullet seating die so I probably need to look for a flat one if the exist. I configured a couple of dummies at .965 and just that little bit of additional band won't allow the round to fully seat. Neck diameter isn't an issue. It crimps under .378 or .3785 with a fairly light crimp and that slips in/out easily. I loaded those in the magazine (dang they're short!) and they seem to feed when I manually cycle through them as long as I stay under .960 they seem to cycle.

For load data, I can't find anything *exact*, but the closest I can find are the following. Note that the lowest starting below is a 115gr @ 3.8 bullseye with a COAL of .997:



Wt.
Bullet
Powder Manufacturer
Powder
Charge
Velocity (FPS)


115
Bushwacker SWC
Alliant
Bullseye
4.0
1,142


Remarks: primer: Federal 100; group (inches): 1.35; maximum











Wt.
Bullet
Powder Manufacturer
Powder
Charge
Velocity (FPS)


104
Lyman 356632
Alliant
Bullseye
4.0
1128


Remarks: overall loaded length (inches): 1.03













Wt.
Bullet
Powder Manufacturer
Powder
Charge
Velocity (FPS)


90
Cast #356242
Alliant
Bullseye
4.0
1060


Remarks: sugg. start load; 19,800 cup; 1.045" OAL; potentially most accurate load


90
Cast #356242
Alliant
Bullseye
5.2
1315


Remarks: max load; 32,000 cup; 1.045" OAL






Wt.
Bullet
Powder Manufacturer
Powder
Charge
Velocity (FPS)


92
Cast #358242
Alliant
Bullseye
4.0
1060


Remarks: sugg. start load; OAL: 1.045"; 19,800 cup


92
Cast #358242
Alliant
Bullseye
5.2
1315


Remarks: max load; OAL: 1.045"; 32,000 cup


115
Cast #358345
Alliant
Bullseye
3.8
1035


Remarks: sugg. start load; OAL: .997"; case: Win; primer: Win 1 1/2-108; 22,800 cup


115
Cast #358345
Alliant
Bullseye
4.9
1200


Remarks: max load; OAL: .997"; case: Win; primer: Win 1 1/2-108; 31,000 cup

[tazman]

As long as the load feeds with that oal you should be fine. When I used that boolit in my 9mm I was able to seat it slightly longer but mine has a looser throat than yours. Even so it was only about 1.010. The only feeding problems I had with this combination were cured by a better crimp.
I am not at home right now so I can't look up the load I used.

[Bonz]

I'd be concerned at 4.0gr Bullseye at that load length

107724

[tazman]

All the data manuals that I can find suggest that 4.0 grains of Bullseye should be quite safe under a 105 grain lead boolit.
I checked Ranch Dog's 100gr loadings(4.8gr) and an Alliant data manual from 2001 which showed 4.9gr for a 125gr lead boolit.

[Bonz]

The depth that you seat the bullet makes a huge difference. On the following screenshot, I just changed the COL from .997 to 1.10 and look how much it affected pressure

107751

[kenn]

Thanks again, Bonz. What does it say for 3.3, 3.4, and 3.5 for .955 to .960 total length?