357 Sig And Cast Bullets

http://castbulletassoc.org/view_user.php?id=7193>mtnwinds

357 Sig isn't different than any other caliber to start cast with.  Hodgdon Data has loads for 357 Sig with Longshot powder for 115, 124 and 147 grain jacketed bullets. Jacketed bullet START loads are safe for cast bullets, HOWEVER the Sig is a high pressure cartridge so DO NOT USE an alloy softer than Hardball Pistol Alloy at BHN 15 for any of the START level loads for the Sig 357. You need that bullet strength for the load level of the 357 Sig or don't bother.

Additionally, don't waste your time with cast bullets that don't have a sliding fit into the chamber throat upon chambering.   Undersized bullets like that in a 357 Sig will load your firearm with lead and shoot all over the place wasting your time, money and any happiness you hoped for. DO what you have to do to get the cast bullets to fit the throat or quit while you are ahead with the 357 Sig. The 357 Sig is not 38 Special you can shoot with soft scrap lead. You need Hardball alloy or harder, BHN 15 to BHN 18.

Find the 357 Sig  Longshot loads at:

http://www.hodgdonreloading.com/>http://www.hodgdonreloading.com/

The START loads from Hodgdon with jacketed bullets  will be safe for cast bullets the same weight or the closest heavier jacketed bullet weight. Cast bullets are much softer and have less friction drag than jacketed bullets do so your actual cast bullet loads will have substantially lower pressure than Hodgdon Data for jacketed bullets. It is also normal for the cast loads to have noticeably higher velocity than the data because of the reduced friction compared to jacketed bullets.

The START loads or very slightly above start level will be fine for cast BHN15-BHN18 bullets that FIT.

STEP 1: determine your chamber throat diameter very accurately, don't use a book number. Chamber cast alloy or a pound cast method are valid to do this and you need a very accurate micrometer to measure the slug from your chamber throat  accurate to .0005". Bullet diameter is ideally equal.

Step 2: check bullet throat fit with an inked bullet dummy round and verify slide marks on chambering.

Get 1 and 2 correct or stop and do not pass go till you do.

The Lee molds TL356-124-2R cast in hardball and un-sized/tumble lubed would be my first choice for the 357 Sig:

http://www.midwayusa.com/find?userSearchQuery=Lee+TL356-124-2R>http://www.midwayusa.com/find?userSearchQuery=Lee+TL356-124-2R

This is a 124 grain  bevel base tumble lube bullet design that is easy to start with and will likely go with no sizing in the 357 Sig if you are a good bullet caster and they drop at .356 to .357” for you as they should with Hardball Alloy. The mold  is available and in stock in 2 or 6 cavity mold models from MidwayUSA for casting. The 2 cav comes with handles but you will have to purchase Lee pro handles for the 6 cav mold.

Start with the 2 cavity $20.99 mold unless you are an advanced caster with lots of experience with 6 cavity molds.  I have been casting since 1957 but started with 6 cavity molds only 7 years ago. It was not an easy learning curve for me with 6 cavity molds. They are great now,  but were very difficult to learn well.

Gary