Can you use 357 mag brass to reload .30 carbine?

G

Gr33zi3

CGN Regular
Rating - 100%
56   0   0
Location
Fort McMurray
Hi all. Im relatively new to reloading, and I recently purchased a small batch of 1f ".30" carbine brass of a fellow cgner. Well now that they have arrived I see that there are a bunch of .357 mag brass mixed in with the .30 brass..

I lack the skill to see any discernible difference between the 2 casings... I just want to know of its ok to use the .357 brass or should I contact the cgner and work out returning the lot? If it helps im gonna be using h110 with a generic 110gr bullet.

Thanks all for your time.
 
Something very odd, here. Looking through Speer #14 loading manual, the 30 carbine has a .360" rim with an extractor groove, and body measures .3547" at .200" ahead of the base. A 357 Magnum has a .440" rim and is a rimmed cartridge with no extractor groove, and measures .379" at .200" ahead of the base. 357 brass has 1.290" (32.77") length; 30 Carbine is same length. I suppose a motivated person could turn down the 357 rim, cut an extractor groove and resize case down to 30 Carbine dimensions??
 
Gr33zi3 said:
https://imgur.com/a/1OdH3L7. Here are some pictures of the brass? 1 in thr middle is the .30 and the 2 on either side are .357 hopes this helps for anyones reference.

Thank you very much for all your answers
Click to expand...

Nope - the 2 on either side might have 357 Mag headstamp, but they are no longer 357 brass. You will have to use a good calliper or micrometer to verify if those modifications are appropriate to use as 30 Carbine. Especially the interior case head thickness.
 
Another issue - 30 Carbine is SAAMI designed for 40,000 CUP maximum. Unmolested 357 Magnum is designed for 35,000 PSI maximum. I do not know how to translate from CUP to PSI in a 357 Mag but I do know that the units are not equal, and their relationship is different to one another depending on the cartridge. I guess I am saying, I know of no way to verify that the modified 357 cases will stand up to 30 Carbine pressures.
 
Gr33zi3 said:
https://imgur.com/a/1OdH3L7. Here are some pictures of the brass? 1 in thr middle is the .30 and the 2 on either side are .357 hopes this helps for anyones reference.

Thank you very much for all your answers
Click to expand...

Holy guacamole batman, someone has too much time on his hands.

There's no way to know how much brass is left at the web. Obviously they've been fired as .30, but it doesn't mean they'll last very long, or at normal pressure, etc. Kinda sad, considering one could just sell the 357 without molesting them and then use the money to buy .30.
 
Other than the case web strength most are rightly concerned about, the photos show a very distinct difference in overall case length. Case length is critical to a .30 carb. round as they headspace on the case mouth (same as .45 Auto if your familiar with those)...as Ganderite says, relegate those .357 cases to the garbage.
 
hatman1793 said:
I want to know how the .223 case become a .30 Carbine case!
Click to expand...

Its simple really. But some effort is needed. You take 223 case you cut it to length of 30 carbine. then you reduce rim of 223 case. This operation may be skipped depending on the brass manufacturer. Some of them have different diameter rims. Then resize in your 30 carbine die. And voila you have 30 carbine case. Load with your favorite bullet and powder.
In my opinion its easier to do it this way than out of 357 cases as OP.
 
Potashminer said:
Nope - the 2 on either side might have 357 Mag headstamp, but they are no longer 357 brass. You will have to use a good calliper or micrometer to verify if those modifications are appropriate to use as 30 Carbine. Especially the interior case head thickness.
Click to expand...

This.

Note how much larger the rim is than the case diameter on proper .357 brass:

619136.jpg


And how that's not the case with .30 carbine:

229197i_ts.jpg


Looks like someone modified .357 brass to use in their .30 carbine? I would promptly pitch that stuff into the garbage, or send it back to where it came from.
 
Just get rid of that brass. Either send it back to seller and give him negative feedback, or take it to the nearest junkyard, as it's still good for a smelter.
 
You must log in or register to reply here.
Back
Top Bottom