Sidearms & Scatterguns Questions on a Glock 31 in .357 Sig

Trevor300wsm

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  • Nov 8, 2009
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    I just traded for two Glocks, a 31 & 33, both in .357 Sig. I have a couple of questions for you Glock gurus.

    1.) Can I buy a factory/aftermarket 9mm barrel for the 31(.357 Sig) and just drop it in or is it not convertible in this manner? If not, what do I need besides a barrel? Where is the best place to buy the above mentioned parts?

    2.) Where are you guys buying .357 Sig ammo in bulk for a good price?

    I've always been a 1911 guy, these are my first two Glocks to ever own. I got the full size to shoot in tac comps that have a pistol section in addition to the rifle. I also got the 33 for a nice little CCW.

    Any help would be greatly appreciated, especially on the barrel conversion to 9mm.
     
    Re: Questions on a Glock 31 in .357 Sig

    Lowe Left & SW99

    Thank you for the info!

    That link is exactly what I was needing. It breaks it all down very clearly.

    What brand & where at to buy decent barrels? I hear alot about the factory Glock barrels and the Lone Wolf barrels. Any better than others? Any place cheaper than others?
     
    Re: Questions on a Glock 31 in .357 Sig

    1) I own the 32 and you can't use a factory barrel because the extractor is different in the .40/.357 models and the 9mm ones. You need to get the conversion barrels from .40/.357 to 9mm. This is the only way it'll function properly every time. Lone Wolf and Storm Lake are both good barrels.

    2) Cheaperthandirt seems to have the cheapest .357SIG ammo I've been able to find and that's still at $18.09 a box for Federal American Eagle type. If you're looking for a carry round I personally carry Speer's Gold Dot in 125gr.

    3) If you're getting a 9mm barrel I'd recommend getting a .40 barrel as well. This one can be a factory Glock barrel. If you ever find yourself in need of a bigger round and are out of .357SIG, the .40 is an ok backup.

    My 32 has the lone wolf barrel.
     
    Re: Questions on a Glock 31 in .357 Sig

    Veer.....oh big fella, what am I going to do with you!?!?
    After reading a number of your posts, I'm a bit seasoned to your style.

    I'm well aware of how to operate Google. Im really looking for first hand expericane from guys that actually shoot the Glocks and have used certain barrels with good results. On the pricing, with Glocks being so common, I didn't know if there might be one "go to store" for anything Glock that was alot cheaper than others. Yes, I could spend hours searching the 1000's of retailers that handle aftermarket Glock parts looking for the best price, or i could just ask here and let someone that is current on Glock info point me in the right direction.

    Guys,
    Thanks for all the help.
     
    Re: Questions on a Glock 31 in .357 Sig

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: trevor300wsm</div><div class="ubbcode-body">Veer.....oh big fella, what am I going to do with you!?!?
    After reading a number of your posts, I'm a bit seasoned to your style.</div></div>

    laugh.gif


    Lots of folks are Google-resistant; you wouldn't be the first.
     
    Re: Questions on a Glock 31 in .357 Sig

    Speaking from experience :

    You CAN drop in OEM 40cal barrels. Use your 357 magazines, they are identical to 40 mags.

    You CAN NOT simply drop in OEM 9mm barrels. They will sorta work, but the outer diameter is a little too small, and the breech hood is too narrow, and the ramp on the front of the chamber hangs up on the slide a bit. Works in a pinch, but not ideal at all. Use G17 mags for your 31, and either 17, 19 or 26 mags in your 33.

    I have found Lone Wolf brrels to function and fit great, and to be well priced.

    Good luck, have fun.
     
    Re: Questions on a Glock 31 in .357 Sig

    FWIW I had a Gen 4 17 when the Gen 4 first came out. I had planned on running it suppressed. I had issues with it from the get go not wanting to eject. I had a Lonewolf black threaded barrel and put it in the Gen 4 17. I couldnt get it to properly function with the LW barrel. FTE 7,8,9 times per mag. Now to get to the point I was trying to make, I then put that same barrel in my 31. It never once skipped a beat. YMMV
     
    Re: Questions on a Glock 31 in .357 Sig

    My cubical mate is a Sig guy, and a 357 Sig guy at that. He refuses to convert to 40 or 9 to save money on training/practice. Anyway, he's used a bunch of this shop's reloads, and had great results so far. This is definitely not FULL POWER 357 ammo, but not bad at all.

    Can't beat the price, $260/1000 rounds

    http://greatlakesammo.com/shopsite/page17.html
     
    Re: Questions on a Glock 31 in .357 Sig

    lonewolfdist.com (lone wolf) has any and every combo of barrel you'd want for the 31.

    beyond that I'd try storm lake barrel as well. Where to buy probably gunbroker or glock talk forum or just go to the lwd website.

    you can use a G22 barrel in it

    you can use a g22/31 conversion to 9mm barrel in it. Even with heavier springs (to help with recoil of the 357sig) 9mm should cycle.

    you can try and run your 9mm through your 357sig mags - if your not happy with the feeding (assuming you have issues) then buy some G17 9mm mags.
     
    Re: Questions on a Glock 31 in .357 Sig

    I owned a Glock 33. It came with and EFK Firedragon conversion barrel in 9mm. For the durration I owned the gun 90% of the rounds I fired were with the 9mm barrel not the factory 357 sig barrel. Never did I have a problem with feeding extracting etc. Now I will say I have heard of problems because as mentioned there is a difference with the extractor I think from a 9 vs a 40/357 Glock but I personally didnt have any problems running the EFK barrel. Good luck to you and safe shooting.
     
    Re: Questions on a Glock 31 in .357 Sig

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: phm14</div><div class="ubbcode-body">I'd just sell it and buy the caliber gun I wanted. Probably less expensive than buying barrels and no fit/function headaches. I'm replacing my Glocks with M&Ps, like a lot of LEO/Mil depts/units both here and abroad. </div></div>

    Yeah that's real sound advice. Sell one Glock to buy the exact same one, only differnce being the barrel. I'll pass. I picked up a G22 barrel and dropped it in the G31 and it's functioned flawlessly.

    Good luck with your M&P's.