As Cast RCBS 9mm Boolits In .357 S&W 686

[detox]

First off here is a link to the mold i want to try.
https://shop.rcbs.com/WebConnect/MainServlet?storeId=webconnect&catalogId=webconnect&langId=en_US&action=ProductDisplay&screenlabel=index&productId=3358
I am thinking i can shoot these from my .357 S&W 686 AS CAST without resizing. I can use the softer 20/1 lead tin mix to form good seal to barrel. A quicker burning powder than unique will help bullet swell just enough to not cause leading.
What diameter do these RCBS 9mm boolits drop from the mold before resizing?

[Rex]

I bet you can make that work. You can always beagle that mold if the boolit is too skinny.

[R.M.]

I think you'd be happier with 357 bullet of the same style. It has a crimp groove, and you can always size them smaller, if needed, for the 9mm.

[detox]

I think you'd be happier with 357 bullet of the same style. It has a crimp groove, and you can always size them smaller, if needed, for the 9mm.

I have the RCBS .358 Cowboy mold with crimp groove. These fall from mold @.361" then sized to .3575" using Lee sizer with Alox lube. I think the crimp groove is for higher recowl powered loads and tubular rifle magazines. The 9mm mold without crimp groove will be OK for what I am doing. RCBS roundnose 38/357 has no crimp groove also.

I am really curious how well this 9mm mold/boolit will shoot in my 686

[detox]

I bet you can make that work. You can always beagle that mold if the boolit is too skinny.

Beagle the mold? How is this done?



....

[MUSTANG]

Detox:

You use some aluminum tape to keep the mold blocks open .001 to .003 to cause the mold to cast a larger boolit. Beagling is a temporary solution, it is not polishing/lapping the mold cavity larger ( a permanent solution).

See this link: http://www.lasc.us/Brennan_4-0_ModifyCastBullets.htm

I use the process on boolits for some of my .30 cal Milsurp rifles with large bores. Also in my Danish Rolling Block with a Lyman & RCBS .458 Molds to get "as Cast" up to the .463 to .465 Range depending on alloy.


Mustang

[detox]

Thanks for explaination mustang.

I just ordered this mold so i do not know what diameter these bullets will fall from mold using 20/1 alloy. Once i receive mold and start casting I will post actuall diameter using my 20/1 alloy and dipper method.

[MaineJim]

I use the RCBS 124 CN in my Glocks sized at .356 and charge with 4 grains of red dot usualy.
Using wheelweight alloy they drop at .358 and i just lube em in a .358 sizing die and they shoot great out of my Dan Wesson .357.
There is a good chance they will cast fat enough,especialy if you sweeten up your alloy with some tin.
Ahh just noticed you said 20/1,thats enough tin ,should work fine.

[detox]

I use the RCBS 124 CN in my Glocks sized at .356 and charge with 4 grains of red dot usualy.
Using wheelweight alloy they drop at .358 and i just lube em in a .358 sizing die and they shoot great out of my Dan Wesson .357.
There is a good chance they will cast fat enough,especialy if you sweeten up your alloy with some tin.
Ahh just noticed you said 20/1,thats enough tin ,should work fine.

That was just the answer I was looking for. Thanks !!!

[detox]

Today i received the RCBS mold and did some casting. Mold does cast to .358 using wheel weights, but this mold does not line up correctly and cast out of round bullets. My boolit measurements are .357 -.359. My S&W 686 has a cylinder throat of .357. I may send the mold back to RCBS with a cast boolit from mold. Would you send mold back to RCBS?

[detox]

OK i think i fixed mold. I had some excess neverseize and lead inside guide pin holes causing mold not to line up. I used Kroil to clean mold. Kroil is the BEST stuff for cleaning molds.

I used my LED 7 power magnifying glass to inspect before and after. Everything is cool now. Try it again tomorrow.

[MaineJim]

Good to hear the mold is ok,yeah Kroil works good as a penetrant.
Lets us know how it went after you cast some round boolits.

[Shiloh]

Sure, if they are large enough. Factory cast boo;its sized at .356 tumble through a 9mm. I can't imagine what they would do through a .38/.357 bore.

An undersized boolit rattling down the bore means time spent mining lead out of it.

Shiloh