Jump to content
Brian Enos's Forums... Maku mozo!

Caliber choice for polymer Open guns


redial

Recommended Posts

Pardon me if this is a noob question (never owned an Open gun) but for those building Open Glocks, M&P's, etc., why haven't I read of them in 357 SIG? I didn't get far using the Search function.

The round would seem to easily make major, work the comp very well and still maintain the mag capacity of the 40 S&W Open rigs. Is there a downside that I'm overlooking?

Thanks in advance,

Mark

Link to comment
Share on other sites

A big downside compared to 9 Major/Minor or .40 is the availability of brass, the price of brass, and the ease of reloading the cartridge. Being a bottleneck round, .357 Sig is a bit of a pain compared to its tapered/straight walled counterparts. (along the lines of reloading rifle vs pistol)

Link to comment
Share on other sites

The Down side is it gives up capacity to the 9mm and the brass is not as plentiful as either 9mm or 40. reloading for it is not as bad as you may think but you do need to lube the cases first.

The Up side is making major in a short OAL gun is no problem with any bullet weight, you get the benefit of the more efficient 9mm comp and the use of lighter bullets than you can with a 40 and more and slower powders than you can run in a 9mm. the capacity will be the same as a 40 or better I can get 1 more round in my extended glock mags with the sig than I can with 40.

On the Brass issue I know there is one of the commercial brass dealers that sells once fired sig for something like $45 per 1000 so it would not be to bad to buy (I cant remember who right now), you can also make it out of 40sw brass you just end up about .010 short I have done this quite a bit and had no problems I just set my dies so I am head spacing off the shoulder not the case mouth and I use a Lee factory crimp die that is the collet type so I get a strong crimp regardless of case length.

Mike

Link to comment
Share on other sites

Is there a downside that I'm overlooking?

"...still maintain the mag capacity of the 40 S&W."

That is probably the big one. Open gun rules allow 9/38 to make Major. With those, you get more magazine capacity.

We do have an Ohio shooter that ran an Open Glock with 357SIG. I think it worked well for him. In actual execution, he didn't have the issues with reloading the bottle-neck cases that we fear (though he is likely handier than most). He is a member here, if you want to hit the search page and see what he has posted (mscott).

Link to comment
Share on other sites

When I bought my first Open Gun (used), it had been built by the original owner in 357 SIG. The load I used was basically the same as the load I use now in 38SC. The major issue was the one others have brought up... magazine capacity. You can get 26 in a properly tuned 170, compared to the 29-30 a 38SC/9mm shooter can. However, accepting that restriction, 357 SIG works just fine.

Link to comment
Share on other sites

Thanks, guys. Much to ponder!

In the polymer guns, it sounds quite doable, with several benefits. If I were building on a traditional 2011 platform, I'd certainly prefer the 38SC over the SIG. And 9Major just gives me the willies.

I'll see if I can find mscott's posts about such a project.

Cheers!

Mark

Link to comment
Share on other sites

The Down side is it gives up capacity to the 9mm and the brass is not as plentiful as either 9mm or 40. reloading for it is not as bad as you may think but you do need to lube the cases first.

The Up side is making major in a short OAL gun is no problem with any bullet weight, you get the benefit of the more efficient 9mm comp and the use of lighter bullets than you can with a 40 and more and slower powders than you can run in a 9mm. the capacity will be the same as a 40 or better I can get 1 more round in my extended glock mags with the sig than I can with 40.

On the Brass issue I know there is one of the commercial brass dealers that sells once fired sig for something like $45 per 1000 so it would not be to bad to buy (I cant remember who right now), you can also make it out of 40sw brass you just end up about .010 short I have done this quite a bit and had no problems I just set my dies so I am head spacing off the shoulder not the case mouth and I use a Lee factory crimp die that is the collet type so I get a strong crimp regardless of case length.

Mike

I reloaded .357 sig for many years and you don't need to lube the cases or trim for that matter. The big issue with .357 sig is bullet set back so you need to have a good crimp or things can go very bad for you. A plus to this cartridge for me was it was very accurate in all the guns I had it in. For the game its a no starter.

Pat

Link to comment
Share on other sites

I shot a 9X25 Dillon, a 10mm necked down to 9mm, for about 3 years. It was AWESOME! Loads of gas, negative muzzle rise, and a blast that would crack concrete. RO's would step back about 6 feet when I shot. But alas, the loss of magazine capacity compared to the .38's was more than i could bear. The .357 Sig is in the same boat. Not enough capacity. sigh

Link to comment
Share on other sites

  • 5 weeks later...

Biggest issue with a bottleneck cartridge is the loss of capacity. If you are not worried about that, then it is a gret caliber to use. You do not need to by 357sig brass. Just buy regular 40sw, lube the cases, and the dies will take care of the rest. My preferred load is:

OAL 1.260

15.6gr. To 16.00 gr of H110

124gr. Berry rnd bullet

This will make 170+ power factor.

Great load, lots of gas to make the compensator work effectively.

DVC

Mark

Link to comment
Share on other sites

Not sure if it ever happened but I remmeber talk some years back about converting a glock 20 to 9x23 Winchester or 38 super (not 9x25 dillon) it was said you could get it to work and have a high cap polimer open gun. Not sure if it ever happened.

Pat

Link to comment
Share on other sites

  • 2 weeks later...

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...