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LW conversion barrel vs. Glock 10mm barrel

Discussion in 'The 10 Ring' started by jedraf, May 3, 2010.

  1. jedraf


    Jun 5, 2009
    I have a question about how tight the round is suppose to fit in the chamber...

    I own a G20, and I just purchased a Lone Wolf 10mm to 40s&w Conversion barrel. When I looked at them side by side, the Glock chamber seemed bigger (10mm barrel diameter wider than .40 barrel).

    With the barrels removed from the weapon, I then dropped a 10mm round in the 10mm barrel and it "wiggles" a little bit. The LW .40 barrel hold the .40 cal round tight. Is this normal? Should I be concerned with the Glock 10mm barrel? Do other G20 owners have the same "wiggle" with a round in the Glock 10mm barrel? Feedback greatly appreciated. Thanks.
  2. 10mmneal


    Apr 7, 2010
    I also just purchased a 20sf and a LW 10-40 barrel for it. The wiggle in the glock barrel is normal. That is how it was designed, to improve feeding reliability. As far as my LW barrel goes it seems to be about the same fit as the glock barrel. However, I haven't measured it and have only given it the "wiggle" test with a .40 round. Both of my barrels functioned perfectly this weekend. Give the LW a try; if you have feeding and extraction problems LW will fix it under warranty. Neal

  3. alwaysshootin


    Nov 14, 2005
    LW, and all other aftermarket barrels, have tighter chambers in all calibers then do Glocks. Glocks are designed to work no matter what. I've owned two G20's. The first being a 1.5 gen, and with the factory barrel, it bulged the brass so bad, I wouldn't consider reloading it. The second was a 3rd gen SF, and it did much, much, better in the buldge department, but still nowhere near what two of my aftermarket barrels would do. For range shooting, and hunting I use aftermarket, mostly for brass life, and oh yea, I shoot lead, almost exclusively.
  4. Kegs

    Kegs Ol 8 fingers ;)

    Oct 26, 2009
    Cold side of conus
    Yep, and preferable for precision and reloading.

    Only if you're reloading. The larger diameter of the stock chamber will bulge brass significantly, which puts more wear and tear on the metal, weakening it. This can cause future case fractures, which are dangerous. The aftermarket barrels have far tighter tolerances and thus do not put as much wear and tear on the brass, so the brass can be reloaded several times. By all means if you are planning on dragging your gun through mud or never cleaning and lubing it, use the Glock barrel. Reliability is the first tenant of the original design.

    Yep. This is so it will continue functioning even if there is grit or pieces of lead/plating/brass, etc. in the chamber. If you want to hit more X-rings, or reload, use the aftermarket barrel. If you want to take the thing into the middle of a war zone where it will be used as a secondary weapon and get sand and **** in it, use the stock barrel. Make sense to you?
    Last edited: May 3, 2010
  5. DrtyHarry


    Sep 26, 2007
  6. HOV


    Mar 5, 2005
    Kegs x3

    I use a drop-in KKM barrel (both 10mm and .40S&W conversion) in my G20 at the range to preserve my brass, but outside the gun runs stock.

    The polygonal rifling of the stock barrel gives great accuracy and increases velocity just a tad over conventional rifling also.
    Last edited: May 4, 2010
  7. wxl


    Mar 15, 2004
    South Texas
    Thinking about a 40 conversion for my G20. Assume the G20 mags will work with the 40S&W?
  8. Roneye


    Mar 21, 2005
    Lonewolfs barrel has a fully supported chamber the Glock doesn't. The Glock barrels polygonal rifling doesn't like lead bullets. The standard rifling of the lonewolf barrel can easily handle lead bullets.
  9. G20gunner


    Mar 7, 2010
    Yes, the G20 mags will work fine with 40S&W.

  10. wxl


    Mar 15, 2004
    South Texas
    Thanks G20gunner
  11. _The_Shadow

    _The_Shadow Ret. Fireman

    Jul 23, 2007
    Southeast, LoUiSiAna
    Aftermarket chamber tolerances are much tighter than most stock Glocks that is one reason for the aftermarket to start with the other was touted as being able to use cast/alloy bullets.

    The great thing about the 10mm platform is the use of conversion barrels, giving opertunity to use 10mm, 40S&W, 9x25Dillon or 357Sig from this platform with a mere barrel swap out. You are using the same feel appeal and sight picture for each, how sweet is that! Gotta luv it!
    Last edited: May 14, 2010
  12. Retired Squid

    Retired Squid

    Jul 7, 2007

    I hate to think of the thousands of rounds fired in very expensive target rifles in rim-fire and center-fire rifles that are using lead in their polygonal barrels. My Glocks only get lead fired trough them except about once a year and would carry my HC L/SWC if I thought that some lawyer would not not try to twist the facts and make out carrying "special" killer ammo.
    Last edited: May 14, 2010
  13. Roneye


    Mar 21, 2005
    I am sure that many here may disagree with me but it is specifically stated in the the Glock manual that comes with the gun and is discussed in detail in the armorers course. Glock along with other manufacturers of polygonal handgun barrels strongly recommend you do not use lead bullets.

    A polygonal bore actually compresses the bullet and rotates it about an axis where as a conventional (rifled) bore only causes the bullet to rotate around an axis. That is why jacketed bullets are recommended in polygonal bores like Glock's, H&K's and the like. It is especially dangerous with the harder lead 40 cal bullets most likely due to the high pressure and hardness of the bullet (15-20 BHN and higher) I have seen more than one Glock barrel that has failed due to the leading one of which in person. If you are an experienced reloader there are some ways to drastically reduce the possibility of failure. But I certainly wouldn't want to take the chance or give a person who is just getting started shooting the impression that it is OK to use lead bullets in a Glock.
  14. Retired Squid

    Retired Squid

    Jul 7, 2007
    The lead ban for pistol's is done because of lawyers and nothing else, I shoot a lot of 10mm auto using mostly lead and have less lead build up in the polygonal rifling of my Glock's then my S&W's, Tanfoglio, T/C G2 or the S&W 1006 I use to have. The worst for leading seems to be revolvers, as my auto loading guns never have had any lead build up to speak of, nor has the Contender.

    Not sure where you get the idea that Polygonal rifling is compressing the bullet and standard rifling doesn't, the whole idea of polygonal rifling was reduce barrel friction from the forcing of a bullet through a barrel that had lands smaller then bullet so the grooves would catch and have squeezed the bullet by grooving the bullet forcing it to follow the twisting in the barrel. When polygonal rifling first came out in expensive target and hunting rifles the complaint or argument against it was that it didn't grip the bullet tight enough to give a proper spin, but that was sort of the whole idea of the polygonal rifling less grip on bullet, which increased the speed (5% to 10% is claimed) and it is why these Glock pistols are so damn accurate. The big deal in the polygon rifling in 22 cal was lead build up was slower to happen allowing accuracy to stay higher because of less lead build up over prolonged shooting.

    The downside is the build up when it does start is rather fast and requires attention quickly to regain accuracy, but they never seem in rim-fire to build to unsafe point before accuracy goes way off. For this reason I can see where this lead build up in a polygonal barrel would be dangerous in your Glock because of failure to clean gun after using a lot of lead bullets the switching to jacketed. It is possible to build up enough lead in conventional rifling to cause a round to stick in a barrel completely plugging the barrel causing a big failure next round.

    Over the years I have bought several 22 rim-fires that were "shot out" according to the owners and took it home and got all the lead out and have good as new gun, I have never seen a 22 rim-fire with worn out barrel from shooting only from excessive cleaning with brush's by competitive shooter.

    One last comment on my G20SF that just a few months old. The 200 rounds of HC L/SWC left very little lead to clean out of the barrel, the 150 rounds of JHP (Nosler, Speer and Hornady) left more copper fouling the lead left behind from the hard cast lead.
  15. 88tlc


    Nov 15, 2011
    new to glocktalk, new to pistols, just purchased a Glock 20, 10mm and have been plinking with it.

    i have also been noticing the bulge in the brass. been using the BVAC 180 grain, and they seem like good ammo.

    some dimensions i was able to pull.

    brass size is .425 outside, and bulges to about .431. i checked the barrel chamber, and it is also measuring .431. with a new cartridge, it does fit loose. after shooting its tight.

    i am not psyched about the bulging.... it seems sloppy, and i want to reload.

    any body have measures for the lone wolf barrel chamber?

    on the brass with bulging, how do you reload these and resize the brass? i have seen some push thru resizing.
  16. ModGlock17


    Dec 18, 2010
    Last edited: Nov 24, 2011
  17. 21Carrier

    21Carrier Until I Gota 29

    Feb 4, 2011
    Hoover, AL
    Not trying to be rude, but it would have been better to start a new thread here on this topic. This thread is a year and a half old. It doesn't matter, just saying. Welcome to GT!

    On to your questions. First of all, the bulging brass is NOT an issue. I have a couple of 10mm Glocks, and I have put nearly 11,000 rounds through the two of them. My G29 has over 10,000 rounds through the STOCK barrel, and most of those rounds have been VERY hot (WAY hotter than the BVAC you were shooting). My brass routinely expands to about .433", and up to .434-.435" at max. Beyond .435", Glocksmiles occur (see pic below), which ruins the brass. The regular bulge, however, is no problem. It is easily ironed out with your sizing die. Even better, you can use a Lee FCD and Bulge Buster kit to do full-length resizing (push through re-sizer), but it's not necessary. The bulge won't hurt anything.

    The bulge CAN work the brass faster, but not much. I have some old brass that just got shot for the SIXTEENTH time! Every firing was through a loose Glock 29 barrel. The only brass that is ruined, in my opinion, is Glocksmiled brass. Under NO circumstances should you reuse smiled brass. It is trash. The only problem you will run into with bulged brass is if you resize it normally (not full-length pass-through), then try to feed it in an aftermarket barrel. Because a normal re-sizer won't size the base, you will likely have feeding issues with the tighter aftermarket barrel. However, if you are just using the stock barrel, it's not an issue.

    About the "sloppy" factory barrel, you are right. It is "sloppy". But it's supposed to be sloppy. Glock intentionally does that on all straight walled barrels to ensure 100% feeding reliability. Aftermarket barrels are nice, but not necessary. The bulge REALLY bothered me at first, too, but now it's nothing. Don't worry about the bulge, worry about THIS:


    If you see this, it's time to back down the load.
    Last edited: Nov 25, 2011