I found a box of 9x21 brass that I had shot thru my P&R Medusa and on a whim I dropped the empty brass into my 986. The 9x21 brass fit the 986's cylinder bore perfectly just like .45 acp fit the M25s and M625s. The cylinder rotated without problem using 9x21 brass in the 7 round moon clips as well as inserted into the cylinder without moon clips.

I have not seen any 9x21 ammo for sale for years but when I shot it out of my Medusa it was less powerful than 9x19 +P and about equal to military 9mm. I would recommend that you NOT shoot 9x21 out of your 986 due to S&W warranty considerations.

Does anyone know why S&W bored the 986 cylinders 9x21 instead of 9x19?

Mark

Maybe they didn't. Factory loaded ammo and new brass is usually made to the short end of the SAAMI case dimension spec, while a chamber would be bored to the long end of the spec. I'd be interested to know what the actual length dimension is of your brass, and the actual depth of your chambers on the 986.

Adios,

Pizza Bob

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Thanks for your comments, Pizza Bob.

The case length for my once-fired Fiocchi 9x21 brass ranges from 20.96mm to 20.99mm.

The depth of the cylinder bore on my 986 is approximately 18.25mm.

My 9x19 brass measures 18.94mm to 19.0mm. That means that about 0.7mm of 9x19 brass extends out from the cylinder (without moon clips) VS 2.7+mm for 9x21 brass.

Mark

I suppect that these guns are an over run of the L frame 9x21 guns made a few years ago for export to Italy.

Tom

I seriously doubt that. While S&W is famous for using up stuff they find in the warehouse, I doubt they would use leftover parts on a new & important introduction of a new product. I'm curious to know more about the Italian guns though. Not mentioned in the SCSW - although maybe they were manufactured after the publication date. I'd say it's about time for a 4th Edition.

It would seem that both the OP's gun and brass are within spec - with the slight exception of the cylinder bore depth. Apparently the taper of the loaded round is such that it will fit past the shoulder milled into the chamber.

Adios,

Pizza Bob

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I will see if I can track down the product code. They were probably done in the last two years.
No such a rare thing...624 cylinders that would accept 44 magnum rounds... 10-8 marked .38 special on the barrel and would chamber .357 magnum are a couple that come to mind.

Tom

This all I could find.
https://www.bignami.it/it/difesa-sic...dotto=360532#1
Tom

Thanks! That appears to be the European version (product code 360532) of the new 986. Domestically produced in 9x19 - however, many European countries prohibit civilians having arms chambered in military calibers, so instead of the NATO 9x19, the workaround is a 9x21. Please note that the cylinder on this gun appears to be unfluted SS, which would preclude its use in the OP's gun, since a titanium fluted cylinder is a rather obvious difference.

Thanks for taking the time.

Adios,

Pizza Bob

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