Jump to content
SASS Wire Forum

.357Sig conversions


Recommended Posts

Some years ago, not long after Sig introduced the .357Sig, I read in one of the Gun Rags where the author had a Colt Delta Elite in 10mm, and had a 40S&W barrel made for it, then had a .357Sig barrel made for it. Was a very interesting pistol. All three calibers used the same slide and magazines, so all he needed to do was change out the barrel and recoil spring to change caliber. 

So in an Alpoesque fashion, I got to thinking about what it would take to convert a revolver to shoot .357Sig. Or maybe a N frame ..357 Magnum revolver to .357Sig. 

Just rebore the .357 Magnum cylinder to .357Sig and whatever else to use the 10mm moon clips from a 10mm revolver? B)

I know that it wouldn't make much practical sense, but it would be interesting.

  • Like 1
Link to comment
Share on other sites

The drawback I would see is the 357 Sig uses a .355 diameter bullet, while your revolver will be set up for .357 diameter projectiles. Like 9x19/.357 Blackhawk Convertible guns, some bullets will not be as accurate. But, definitely a neat idea.

Link to comment
Share on other sites

I have had a couple of .45 ACP revolvers and looked at the S&W 10mm revolver.  A consideration has to be bullets coming loose due to the increased recoil and taper crimp.

The 10mm has more of that issue than the .45 ACP.

I would think that the .357Sig would be similar.

Link to comment
Share on other sites

5 hours ago, Sgt. C.J. Sabre, SASS #46770 said:

Just rebore the .357 Magnum cylinder to .357Sig and whatever else to use the 10mm moon clips from a 10mm revolver?

 

If you bore the cylinder 10mm case-size all the way through the freebore is going to allow quite a bit of bullet slop (potentially) before it hits the forcing cone.  

 

I would think you would want to bore the chambers so the cartridge headspaces on the shoulder, so the chamber in front of the bullet would be .357, not 10mm.

Link to comment
Share on other sites

Had the S&W 10 mm revolver.  A good friend, now deceased, traded me out of it.  A good gun, and I was testing a rimmed case I worked up for it that was promising (no clips needed!) when I let it go.  I have been impressed by the 357 SIG cartridge performance.

  • Like 1
Link to comment
Share on other sites

26 minutes ago, Stump Water said:

 

If you bore the cylinder 10mm case-size all the way through the freebore is going to allow quite a bit of bullet slop (potentially) before it hits the forcing cone.  

 

I would think you would want to bore the chambers so the cartridge headspaces on the shoulder, so the chamber in front of the bullet would be .357, not 10mm.

Perhaps "bore" was the wrong word. Rechamber the .357 chambers to .357Sig so the cartridge headspaces on the shoulder, and use the 10mm clips to allow the ejector star to extract the casings.

Link to comment
Share on other sites

Generally, bottle neck cartridges are a pain in revolvers.  Some have been done. 357/44.  256 Hawkeye but case setback tend to bind the cylinder can be a problem.  Older dash series. 38/40 and 44/40 ran at lower pressure work good.   Just my thoughts.   GW

Link to comment
Share on other sites

I have a police trade-in G22 Glock (.40 S&W).  A 9mm "conversion" barrel and G17 magazines and it's a dependable 9mm P.  With a .357 SIG barrel, well, it just drops in and uses the G22 magazines just fine.  Added a Advantage Arms .22 lr. conversion kit and I have a 4-caliber platform.  Can't imagine much more versatility than that. I haven't had any problems finding .357 brass and in a pinch I'm told it can be made from .40 S&W cases, slightly shorter but it works.  I do size my .357 SIG to headspace on the shoulder.  Wilson makes a good headspace gauge for that.

  • Like 1
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.