I'm making this topic over here since it is not getting much exposure on the range report forum.

Range report 1:
Put 75 rounds of Double Tap 200 grain Noslers and hard casts through it and my KKM barrel. Very, very accurate. But I had 2 failures.

Description of these failures: case ejected properly, slide locked rearward. All you gotta do is pull back on the slide and release to fix it...

Range report 2:

Threw a 3020-2 extended slide stop lever on. No more slide lock back malfunctions after 105 rounds of the same ammo.

But this time I had 3 FTF's where the next cartridge was stuck going into the barrel. I see these same exact failures all over this website. I marked the two culprit magazines. The gun was also shooting an inch left at 10 yards...upon further examination the rear sight was slightly left on the night sights I added between today and the first trip. Fixed that.

So I'm wondering if the new failures were magazine spring related? The cartridges were slightly crooked coming out of the magazine where they were stuck.

Range trip 3
This time with extra power mag springs. Same deal with the FTF's. I have Gen 4 extra power RSA's on backorder from Glockmeister...does anybody else make them for the Gen 4?

And with the extra power mag springs I have a new issue...slide locking back on the last round.

Not to mention brass lands 20 feet away...but that has been happening from day 1. I REALLY want to try an extra power RSA.

Did you use the Wolff 10% springs?

I only have issues with the last round feeding from mine. Slide locks back as if the mag is empty. I can use the slide stop lever or sling shot that last round into battery.

Quote from: PandaBear on March 26 2014 11:10:37 AM MDT
Did you use the Wolff 10% springs?

I only have issues with the last round feeding from mine. Slide locks back as if the mag is empty. I can use the slide stop lever or sling shot that last round into battery.

Yes.

You've probably read through Panda and my thread here already.  Curious:  What do your stock mag springs measure from the point of the V in the first V of the spring to the other end?

Wolff 10% springs are longer than the standard Glock ones.

Were the failure to feed with the stock barrel or the KKM?

Lonewolf makes an adaptor for a Gen 3 spring to be fitted into a Gen 4 gun. I think some of the guys here have them. Other than that, to my knowledge Glockmeister is the only company making a dedicated Gen 4 RSA with heavier than stock weights.

Chucky, I will check when I'm home tomorrow.

4949, do you have links to the adapter and 22lb and 24lb RSAs? Im having trouble finding anything other than Glockmeister stuff for some reason...

I've only shot the KKM barrel. I intended to shoot the stock barrel but I keep forgetting to bring it. But the way the slide keeps catching the rounds before the mag has pushed em up all the way leads me to believe it is slide speed related and not barrel. But I still intend to test the stock barrel.

Try this link, Tom:

https://www.lonewolfdist.com/Products.aspx?CAT=83

Quote from: chucky2 on March 26 2014 02:08:38 PM MDT
You've probably read through Panda and my thread here already.  Curious:  What do your stock mag springs measure from the point of the V in the first V of the spring to the other end?

http://i.imgur.com/HE6EFXA.jpg

That's about a half inch longer than mine were.  With my stock mag springs stretched to 6" my FTF was drastically, although not completely, reduced.

Man these Gen4's have problems, yikes!  Got to wonder if Glock knows or if they think all is well or it's just an ammo problem every time.  How is it possible ammo that works fine in Gen2/Gen3/Gen3SF's suddenly has all these problems in Gen4's?

Are the Gen3's good to go like the SF's?  Local gun shop has a regular 20 Gen3...I like bigger grips. I ask this because if this Gen4 cant be fixed I'll have Glock replace it with another 9mm....and get the 20 from the shop.

I haven't heard of any problems with the standard Gen 3's.

Quote from: radiotom on March 28 2014 09:51:05 PM MDT
Are the Gen3's good to go like the SF's?  Local gun shop has a regular 20 Gen3...I like bigger grips. I ask this because if this Gen4 cant be fixed I'll have Glock replace it with another 9mm....and get the 20 from the shop.

I had problems with my gen4. Bought a used gen 3 non SF and have yet to have an issue.

Tested the Parabellum Research 165 grain FMJ V-Supreme ammo today, 50 rounds...

My back is still a little sore, it went out last Friday, weather yesterday was horrendous, over 4"+ rain yesterday.  Some of the ranges were closed; however I was able to get into one although it was sopping wet.  Wind was stiff and moving clouds made some shots not register on the CHRONY.

Here are the results of the range trip, Glock 20 SF.
NO failures of any kind.  I did fire 15, 5, 3, 2 from each of two different magazines.

Factory barrel/spring
1290, 1344, 1317, 1340, 1317, 1340, 1280, 1334, 1328, 1191,
1323, 1360, 1380, 1322, 1327, 1324, 1343, 1319, 1331

Factory Barrel Wolff Gun Springs 22lb non captive recoil rod and springs
1295, 1361, 1330, 1335, 1347, 1246, 1342, 1325, 1321, 1333,
1347, 1335, 1328, 1348, 1336, 1333, 1310, 1310

Those were the rounds that registered; I was sort of rushing through this, before anyone else showed up. 

Case expansion was 04330"- 0.4340", typical of Glock Factory Barrels.

However the main part of the testing was gun functions,  I shot singles, double taps and triple taps, testing for any failures that could possibly cause a stoppage.  However the Glock-20 SF pistol was flawless in stock configuration and with the use of the non captive Wolff recoil 22lb spring setup using different magazines, loaded with varying amounts of the ammo.