G20 highpower loads

Discussion in 'General Firearms Forum' started by rexfire, Sep 30, 2020.

  1. rexfire

    rexfire

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    I am looking at getting a woods gun for bears, etc and shot the g20 and this will probably be the gun. Then i start reading more about reliability issues shooting high power loads. I am sure this info is already in the forums. But what is the recommended. Upgrades to make it handle underwood type rounds. A better barrel and heavier springs? Anything else? Do these upgrades make it reliable to trust.
     
  2. K31Scout

    K31Scout

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    My handloads are hotter than Underwood following Hornady's manual and my G20 gen 4 runs perfectly. I shoot BBI coated lead 200gr FN and Hornady XTP 200gr with 600-707 ft lbs of energy.

    I shoot both an OEM barrel and KKM. The reason for the KKM is kinder to the brass due to the tighter chamber. I like to get lot's of loads from my brass.

    The only problem I've had with reliability is from SWC profile bullets that don't feed well in either barrel. The big wide flat nose Underwood and Buffalo Bore bullets feed fine.

    The new spring in the gen4 is fine for all loadings.
     

  3. DonD

    DonD

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    I'm not dumping you in the sense that I too am a 10mm enthusiast but what follows are the published data on Underwood;
    220 gr 1200 fps/703 ft lbs
    200 gr 1250 fps/694 ft lbs

    I get 1369fps/645ft lb using Hodgdon's starting loads with CFE Pistol and Underwoods 155gr goes to 1493fps/767ft lbs. Don
     
  4. K31Scout

    K31Scout

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    AA#9 gets me 1263fps average with BBI 200gr FN for 709 ft lb energy. Accurate too and of course reliable.

    The Underwood is not always what they state on the box at least in my G21 .45 Auto. About 100fps short. Never shot Underwood 10mm but have loaded similar profile bullets.
     
  5. IAhunter

    IAhunter Venor ergo sum

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    My stock G20.4 does well with the 200 grain hard cast load from Underwood or my hand loads consisting of an 180 grain XTP on top of a healthy dose of A#9. It’s my woods gun and loaded with the Underwood load in the high country for bears and my hand loads in the high desert for bears/varmints/ misc. threats.
     
  6. Tito's Glock

    Tito's Glock

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    Buffalo Bore is great ammo, as is Underwood and Double Tap.

    Buffalo Bore developed a solid alloy bullet specifically designed for anti-bear. If you buy from Buffalo Bore don't buy it direct, they are on top of a mountain and have to charge you butt-loads for shipping.

    I run a 22 lb. Wolf recoil spring.
     
  7. sourdough44

    sourdough44

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    Are you set on the Glock 20? Is there a certain location for most woods outings?

    I have a relative that has a black bear guiding setup. He often carries a Glock 22 when going on retrieval, besides the long gun. He has used the handgun a few times to dispatch bears. I bought him some extreme penetrating Underwood rounds when he complained about penetration. He hasn’t used them yet on game.

    My more serious handgun is a 4.2” Redhawk in 45 Colt with hard cast handloads.
     
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  8. rexfire

    rexfire

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    we go all over camping. So grizzly, black bear and everything in between. I know 10mm isn’t a hand cannon, but it has worked on grizzlies. More black bear than grizzly though is what i would encounter.
     
  9. Jonny Yuma

    Jonny Yuma

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    I always thought Glocks were at their peak of reliability right out of the box, then I bought a G20-3.

    It worked fine with Winchester white box and Federal fmj, but it wouldn't feed Underwood 200 grain. I wound up putting in a 24# rsa and now it functions with everything.

    Still, I was a little disappointed because I wanted it to run with full power 10mm ammo in stock configuration. It's seems that most people who have G20s have to buy a stronger rsa in order to make them run with full power ammo. I wish Glock would address that issue.
     
  10. sourdough44

    sourdough44

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    You do get more rounds with the G20, lighter too than most large revolvers.
     
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  11. Borg Warner

    Borg Warner

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    In my opinion most people go too heavy with recoil springs making the gun unreliable with anything but heavy loads. I recommend the Lone wolf 17 pound spring with the stainless steel recoil spring guide. If I were to go any heavier I'd only go as far as a 20 pound spring rather than a 22 pound.

    That's what I have in my Gen 3 G20SF and it's reliable with all ammo. I especially like the Underwood ammo. I put an aftermarket barrel in mine only because I wanted a longer barrel but the factory barrel will work even with hardcast lead as long as you clean your barrel after shooting so that the lead doesn't build up.

    Underwood powder-coats their ammo anyway so it's not a issue.
     
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  12. Jonny Yuma

    Jonny Yuma

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    Yep, and it's kind of indestructible too.
     
  13. Jonny Yuma

    Jonny Yuma

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    My plan was to run a heavy spring with Underwood ammo and the factory spring with weak ammo. I'm surprised that the 24# spring works as well as it does. I guess every gun is different.
     
  14. Taterhead

    Taterhead

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    I have shot plenty of hot and heavy ammon in my G20. Mostly handloads.

    Reliability is excellent. I recommend finding the ammo you want and shooting it bone stock. Then see if there is a problem that needs to be addressed.

    If shooting any kind of cast bullet, ensure that the diameter is no less than .401" or results will not be good.

    My favorite ammo to carry in nature is one of my LBT 204 gr WFN. That is loaded over Accurate No. 9 to 1250 fps. Cycles beautifully in stock configuration. With a Wolff 22# RSA, I get slide-over misfeeds with hot ammo. Stock RSA has been most reliable.

    [​IMG]

    [​IMG]
     
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  15. ThomasM4

    ThomasM4

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    For my stock g20 I really like 9.2gr of longshot with anything 180gr.
    Need to chronograph that load now that I think about it.
     
  16. Taterhead

    Taterhead

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    Here are some data points for you:

    With Longshot under a 180 XTP in my G20 gen 3

    9.1 gr 1171 fps
    9.3 gr 1185 fps
    9.5 gr 1187 fps

    10 shot averages. CCI 300 primers.
     
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  17. Borg Warner

    Borg Warner

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    I'm only going by my own experience. I would recommend trying the shoot the ammo you want with the factory weight spring and seeing how it works and then trying a heavier spring and see how that works.

    With the lone wolf stainless recoil spring guide the front of the guide rod is removable with an allen wrench and you can try different weight springs. Some people like to put Loctite purple (most easy to remove) on the screw to make sure it never comes loose but I've never removed mine.
     
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  18. Jonny Yuma

    Jonny Yuma

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    I shot it with the factory 17 pound spring, and it worked fine with weak loads but not Underwood. The 24# spring works fine with both. Not sure why, most people seem to have better luck with something lighter than 24#. I think my gun is an anomaly.
     
  19. Scott1970

    Scott1970

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    9.3 gr Longshot with a 180 gr FMJ was giving me an average of 1300 FPS in my Gen4 20 with a 6” Lonewolf barrel.
     
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  20. Scott1970

    Scott1970

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    That is a really sharp looking bullet! I’ve been wanting a big meplat 10mm, and I’ve never heard of LBT molds.
     
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