Hello I'm new here but not new to 10mm's. I have a kimber eclipse and glock 20sf. I found a g 40 mos at my lgs and purchased it yesterday. I ran 2 mags of underwood 180 gr xtp through it last night and loved it. I'm going to start loading for it this week. Does anybody have any idea on where i can get a heavier recoil spring or if one is needed? I've got several lbs of bluedot and a #9 along with 180 gr xtps. Any help or info on loads would be appreciated. Thanks
Gen 4 upgrade RSA's are not (yet) available from the aftermarket, only factory weights. If you need to adjust the spring weight, the only option now is using Gen 3 RSA's with a Gen 4 adapter (more info on that, if you need). No biggie, if that's what you need. But, do you need to do that? If it shoots well with Underwood 180 gr. XTP rounds, you likely won't. Unless you have a specific objective, it isn't likely you'll handload any rounds "hotter" than that. None of the published book loads are heavier.
I was unaware the rsa was not available yet. I won't be loading as hot as that underwood ammo so I will just run it as is for now. I contacted kkm today about a 6in glock 20 barrel and was informed that barrel wouldn't work in the glock 40 mos. I was told the we're working on a 40 barrel. Anybody have any experience with this?
I don't know why KKM says their barrels won't fit. Gen 3 LWD barrels, 6.02+, fit the G40 fine. They recommend the conversion RSA with heavier ISMI spring (20#) for Underwood and BB ammo, but the factory slide and factory RSA will fit their barrel. Their conversion barrels also fit (9x25D, etc.).
The lonewolf barrels work just fine in the 40. I have over 400rds through my barrel in the 40 no unusual rub marks etc.
get the gen 4 to gen 3 adaptor and g20/21 ss or ti guide rod. I have a 20lb in my 40. Think I'll try heavier though.
Thanks guys guess I'll look into the lonewolf barrel.
I've been shootin my 6 inch KKM barrel out of my G40. It is just a hair longer than the stock G40 barrel but I can't see any other significant difference. I bought it for my Gen 4 G20, sold my G20 and bought the G40. I've put 50 factory rounds, 50 handloaded practice rounds and 30 or so handloaded 200 grain WFNGC rounds through it with no problems. Here's a couple pics comparing the two for reference.
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Quote from: sep on August 28 2015 11:17:38 PM MDT
I've been shootin my 6 inch KKM barrel out of my G40. It is just a hair longer than the stock G40 barrel but I can't see any other significant difference. I bought it for my Gen 4 G20, sold my G20 and bought the G40. I've put 50 factory rounds, 50 handloaded practice rounds and 30 or so handloaded 200 grain WFNGC rounds through it with no problems. Here's a couple pics comparing the two for reference.
It could be a timing issue (not unreasonable), or total BS. Maybe $$ or just uncertainty. KKM makes a good product, but this makes little sense (KKM's claim, not your post).
I just emailed KKM about using the G20 barrel in the G40. We'll see if they give me the same answer they gave jrod. :D
I emailed then Friday again just to try and clarify. I never got a response back. The email I got originally says it is from the vp of kkm. I would assume he knew what was going on. Is there much difference in quality or accuracy between kkm or lonewolf? Anyone have a prefrence?
Quote from: jrod on August 29 2015 07:18:34 PM MDT
I emailed then Friday again just to try and clarify. I never got a response back. The email I got originally says it is from the vp of kkm. I would assume he knew what was going on. Is there much difference in quality or accuracy between kkm or lonewolf? Anyone have a prefrence?
Both are good, for a drop-in barrel. I wouldn't say one is better than the other, but I prefer Lonewolf. Initial cost is one thing, but customer service, if it means anything to you, it's LWD all day long (instead of all month long with SL and KKM). All my KKM barrels have been traded off, and I now use LWD for everything from 9mm to .460R. Only one barrel got sent back, and that was to increase the freebore (my choice, not a failure). Storm Lake were crap, in my experience, and Bar-Sto are too expensive and didn't fit out of the box (not necessarily a bad thing, but they didn't shoot any straighter).
The Lonewolf barrels are made overseas and are thus a little cheaper. I have two of them, and can say they are more accurate then the Glock stock barrels.
Very good product, especially for the money.
Actually Lone Wolf was using Dasa Machineries now in Duluth Georgia that is producing their barrels now
LWD shows this...
QuoteDasan Machineries Co. LTD
Dasan is headquartered in South Korea and has recently opened a manufacturing facility in Duluth Georgia. Dasan has been manufacturing barrels for some of largest brands in the world for more than 20 years and is well known for producing a high quality yet still value priced product.
I just emailed Lonewolf to see if their G20 6.02 inch barrel will safely work in the G40. Should be interesting to see what they say.
Quote from: The_Shadow on August 30 2015 08:31:48 AM MDT
Actually Lone Wolf was using Dasa Machineries now in Duluth Georgia that is producing their barrels now
LWD shows this...
QuoteDasan Machineries Co. LTD
Dasan is headquartered in South Korea and has recently opened a manufacturing facility in Duluth Georgia. Dasan has been manufacturing barrels for some of largest brands in the world for more than 20 years and is well known for producing a high quality yet still value priced product.
Sounds good let's hope the price doesn't increase per barrel.
The mass of the G40 slide is greater than that of a stock G20. That should have a positive effect on reducing the effect of the recoil. In essence, you should not have to increase the the weight of the recoil spring as much or any at all for the same load that you were shooting in a G20.
You can calculate all this if you want to go to a little trouble. However, my Lone Wolf G20 LS with their 6.02" barrel works fine with an 18# spring
and a solid SS captive rod. It is actually more comfortable to shoot and more accurate than the standard G20 with a 22# spring using the same load.
Don
Here is the wonky thing...
I was gonna do the math on how the extra weight would impact slide velocity. lagarto is spot on that you would expect that long slide to have a good bit more mass.
So, since I don't have one of each to weigh, I thought I would just look them up on Glocks website and subtract the mass of the G20 from the G40.
Shock...
The unloaded weight of the G20 is more than the empty weight of the G40, both Gen 4. G20 Gen 4 is 870 grams, while the G40 Gen 4 MOS is 798 grams.
Apparently the G40 slide is narrower than the G20 slide, and their mass is nearly the same.
I got an email today from kkm. They said they are currently testing there g20 barrel in the 40 and they should have an answer shortly.
Sqlbullet
That's interesting.
Since I have different site systems on my 20/20LS slides, I can't get a precise weight difference. I estimate that it is about 55 grams. I'm sending an Email to LW for the exact weight of each bare slide.
I've always assumed that Glock used the 17# system on all Pre Gen 4 models to make it functional with a broad range of ammo.
What's your thinking on why they do it?
Got a reply from LWD. It's actually 40 grams difference.
Don
There's no need to "gild the lilly". The springs you have are just fine.
Quote from: sqlbullet on August 31 2015 08:02:36 AM MDT
Here is the wonky thing...
I was gonna do the math on how the extra weight would impact slide velocity. lagarto is spot on that you would expect that long slide to have a good bit more mass.
So, since I don't have one of each to weigh, I thought I would just look them up on Glocks website and subtract the mass of the G20 from the G40.
Shock...
The unloaded weight of the G20 is more than the empty weight of the G40, both Gen 4. G20 Gen 4 is 870 grams, while the G40 Gen 4 MOS is 798 grams.
Apparently the G40 slide is narrower than the G20 slide, and their mass is nearly the same.
. Are they still doing the slim slide? Thought they went back to the 10mm 45 width. Any owners let us know? Thx.
subjectively, the slide width seems the same as my 29. (I don't have any other glocks) Just the 40 & 29.
I have my micrometer packed away. House for sale and a lot of reloading stuff is packed away. Sorry.
Good to know. I don't think the 9mm width slide was doing too well with full 10mm. They've never changed the specs on their website. You can bet it actually does weigh more than a Glock 20.
I just weighed my G40 without a magazine using my 50 lb digital fish scale. It weighed 2 lbs 2 oz. That's with a 6 inch KKM barrel, Zev Tech Fulcrum trigger, Dawson Precision sights and stainless steel Gen 4 RSA. Empty magazine weighs 3 oz.
Slide width just forward of the ejection port is 1.120.
What does just the slide weigh
My slide with Dawson Precision sights (adjustable rear and fiber optic front) weighs 1 lb 6 ounces.
Thanks.
Anyone have a G20 slide they can weigh and post the results?
Quote from: sqlbullet on September 14 2015 07:51:40 AM MDT
Thanks.
Anyone have a G20 slide they can weigh and post the results?
Sqlbullet,
I weighed my G20 slide. It is 17.42 ounces.
based on those two numbers, 17.4 oz for a G20 and 22 oz for a G40, the slide velocity would be right at 20% less when the bullet leaves the barrel.
Wow, I wonder if the G40 won't suffer from the FTF issue(s) some Gen4 G20's suffer with real power 10mm ammo. Too bad the sample size of G40 users will be even smaller than Gen4 G20 users... :(
If someone has a G21 slide and barrel they can weigh and post, I can compare it to a 230 grain FMJ load in a G21.
I haven't had any FTF with my G40. I've shot Armscor factory 180s, handloaded 180 Berry's with 6 grains of Win 231 for an average velocity of 1076 fps and 1200+ fps loads handloading both Beartooth and Double Tap 200 grain WFNGCs. It seems to run fine with whatever I feed it. Of course, the distance the cases eject are quite different between factory and 200 grain handloads. So far, so good.
Quote from: sep on September 17 2015 08:53:06 AM MDT
I haven't had any FTF with my G40. I've shot Armscor factory 180s, handloaded 180 Berry's with 6 grains of Win 231 for an average velocity of 1076 fps and 1200+ fps loads handloading both Beartooth and Double Tap 200 grain WFNGCs. It seems to run fine with whatever I feed it. Of course, the distance the cases eject are quite different between factory and 200 grain handloads. So far, so good.
That is great to hear! Thx