View Full Version : G20 failure to feed with high power loads
This time I was using 180gr XTP at about 1330 fps with stock barrel and 22# spring, flat coil by Lone Wolf. My wife shot 5 rounds, two of which jammed on the left side of the chamber. I fired the remaining 9 shots without incident. This is not the type of reliability I was expecting.
Talked to Glock tech support they said try different ammo. The guy was nice enough but said he couldn't help since I was using aftermarket spring. Let them know if I was having problems with stock spring. He said their advice would be the same, try different ammo and see if that solves the problem.
Other details-
9.5 grains Longshot
CCI 350 primers
1.260 COL
New Starline brass
Any ideas?
Happened with the wife? She might not have had a firm enough grip on it (limp wristing).
That is a good point about her having a softer grip than I am using. But I really don't understand how that would make a difference.
If this is a self defense firearm then shouldn't it function regardless of grip strength? Just thinking about less than ideal shooting conditions, one handed shot for example.
I cycled it manually with the same magazine to see if I could get it to happen on the bench, no issues. But what I did find is copper residue on the feed ramp which was left of center. This shows a tendency of feeding to the left.
8141
click to enlarge
sbgixxer
08-11-2011, 14:51
I would lean towards what Graves said. My wife had the same issue when she started shooting. I can't recall it happening with any Glocks but with other auto hand guns especially of larger calibers. If it's not happening to you at all, it's a pretty good sign that that's the case. I would think it would be even more likely with a strong 10mm load since the slide (and stronger spring) is essentially relying on your wrists to provide enough rigidity to fully activate the spring. If that doesn't happen, you end up with an incomplete cycle.
SA Friday
08-11-2011, 15:08
Absolutely positively limp wristing the gun. Also, a heavier recoil spring is going to make the problem worse. Go back to the oem spring weight.
Ok, so I get it now with the resistance needed for the spring. I also discussed this with my wife and she thinks she was limp wristing. She was trying to relax and not anticipate the recoil for better accuracy and let the gun go where it wanted to. Imagine the hand waving she just used This is what she does with the G23 (all stock and typical factory 180gr fmj) and has never had any issues. I will try with the complete stock set up and see what happens.
I did get one jam with the stock barrel on another day when I fired it but don't recall what load I was using. It was less than what I posted, I'm guessing 1250 fps range and that was a 180 gr Montana Gold CMJ. Can't say for for sure what spring I had in it. It will be a while before I get to the range again. I will be keeping more detailed notes.
On a general note. When I was shooting a friends .44 mag Ruger redhawk I was under the impression to not fight the recoil and let the gun recoil where it wanted to. In applying this same principal would this be considered limp wristing?
Maybe I don't know as much about hand gunning as I thought?
SA Friday
08-11-2011, 19:30
Well, the anomaly of jamming a gun from too loose a grip is a semi-auto centric issue. It's not going to matter with a revolver. If you don't lock your wrists when shooting a semi you can absorb enough of the energy from the recoil to stop the slide from cycling completely. The heavier recoil spring means you need even more energy than normal to get the slide to unlock and start moving to the rear. The heavier recoil spring will also cause the slide to go forward with more energy and upon completing lock-up, causes the muzzle to nosedive. This means you now have to bring the muzzle back up to acquire a sight picture.
I'm not sure why you felt the need for a heavier recoil spring, but in a Glock, it's just not going to do you any good. Put the oem spring weight back in the gun. I prefer to change to a non captured SS guide rod, but it's really not an issue unless you are shooting it competitively. When shooting the gun, lock your grip, wrists and elbows in place. They should be a rock solid platform. Then relax your shoulders and everything else.
SA Friday
08-11-2011, 19:40
http://www.youtube.com/watch?v=ysa50-plo48&feature=youtube_gdata_player
This helps too.
To answer your question on why. It was my understanding that using high power loads required the heavier spring to cycle correctly. Also, it was my understanding that shooting hot loads with stock springs could create a feed issue do to the slide moving too fast. Additionally, it was my understanding the not using the heavier spring would beat up the slide and frame.
Thanks for the extra info and posting the video, very informative. Both my wife and I watched it. I'll post up after some range time.
tactuppernut
08-15-2011, 11:30
Check your frame's spring tunnel to see if aftrmrkt. spring is contacting/binding (if so, replace and buff damage). Also clean magazine & re-tension spring (by stretching a little). Chances are, your aftermarket recoil spring is allowing less breech relief (the amount of space between breech-face & back of mag) which means your mag spring must "snap" next round into magazines' feed lips faster than for a stock Glock recoil spring (which allows slide further rearward travel). If re-tensioned mag. spring works, replace with an ISMI Brand spring, or Wolff XD spring(about $10 Brownells). Last item to check is the extractor for wear on underbelly, factory replacement trigger block w/extractor is about $12(and 2 minutes to replace). If there is no scarring in frame's spring tunnel from spring increasing its' diameter,and you can't feel/hear it binding during manual cycling, my money is on mag. springs. Just went through same ordeal highly customized G21 including a Sprinco recoil system (of which I highly recommend) that had all 3 issues. It's now finally back in the nightstand.
PS- as a properly tuned Glock will cycle when dangled from a string, "limp wristing" will not cause a malfunction.
tactuppernut
08-15-2011, 11:58
I just went through this with a highly customized G21 that would only mis-feed (as yours is) when Sprincos' recoil system was installed. First, check spring tunnel in frame for signs of spring contact. If tunnel is scarred, spring is "snaking" excessively during compression, or O.D. has increased, replace spring and buff scars. Check underbelly of extractor (the "pointy" arm above mag. lips) for wear (especially if using steel-cased ammo). Replacement factory trigger block with extractor runs about $12 (Brownells) & takes 2 minutes to replace (must R&R all 3 pins and swap trigger bar & spring over). Before replacing extractor, my money's on the magazine spring. Even if you never load mag. to capacity, never store loaded, those springs still lose tension over time (as was my case). Disassemble, clean and silicone wipe inside of mag.. Re-tension spring by stretching before reinstalling. If this alleviates mis-feed, replace with ISMI spring (1st choice), or Wolffs' XD mag spring.
Good luck.
I have an OD G20 and have fired Police reloads and everything else I can think of and have not had one hint of a problem.
Here's an update. Shortened the COL to 1.255. Tried with the stock spring and 22# springs with XTP's and Montana Gold CMJ both in 180 gr. Same recipe. Wife tried it with softer and stronger grip. Basically no difference. I tired it single handed with stock and 22# springw. I'm not going to keep chasing this with a brand new gun, I think I'm sending it for warranty via Gun Genie.
Did you ever return the gun to stock and shoot factory ammo as Glock recommend ? Glock will return the pistol to stock and test it with factory ammo . As to warranty they specifically state no reloads / reman ammo and the gun has been modified which you have all ready informed them when you called tech support , warranty is iffy at best .
When a Glock wont run with reloads and aftermarket parts... Those are the first two things I would change.
Yes I returned it to stock form during some of my most recent testing. Still jammed in stock form.
Factory ammo, no. The whole point is not to have to pay $30 for a box of Buffalo Bore. And for me, I didn't buy a 10mm auto to shoot light factory loads.
I suspect you will not be happy with what Glock is going to say then . The idea is if the gun runs stock on sammi spec ammo the problem isn't the gun but what its fed . The manufacturer designed it to run in the configuration it shipped in with industry standard , SAMMI spec , ammo and if you modify it and run nonstandard ammo thats on you not warranty.
The Glock 20 is being advertised as shooting loads approaching .41 magnum loads.
http://www.galleryofguns.com/genie/default.aspx?pg=list&mfg=glock&mdlno=20SF+(Short+Frame)
As I said, I have problems in stock form. I believe my cartridge dimensions to be within spec. $30/20 rounds is expensive testing.
http://www.buffalobore.com/index.php?l=product_detail&p=114
The 180gr JHP are what I measured in the store. The G20 should run hot loads, in stock form, per advertising and based on what others are doing. Maybe I should go shorter COL?
Your missing the point nothing was said about using the hot Buffalo bore ammo for testing which IIRC is not SAMMI spec . If you never try something other than reloads your chasing your tail . There may very well be an issue with the pistol but until you return it to OEM configuration and try factory ammo you'll never know . Have you checked your ammo with a case gauge ? Are you running the pistol bone dry without enough lube ? There is an article that Vickers wrote on this that is being redone and not on the site now . The just of it is there is no such thing as to much lubrication regardless of conditions . The copper anti seize that Glocks ship with doesn't cut it .
As to the claims on Buffalo Bores site I'm wondering how they suspended physics by generating more velocity without more pressure , also the recoil spring has a minimal effect on keeping the slide in battery this is a function of the camming angles on the recoil lugs and the barrel shoulder . The 10mm load was downloaded 1st because it was breaking guns and then to reduce recoil not just for recoil .
Depending on how the cartridge jams, nose up or nose down will tell you if its too short or too long.
When you start shortening the OAL, pressures can skyrocket in a hurry.
SA Friday
08-24-2011, 07:30
I will say, I've ran into one glock out of hundreds that just wouldn't run. I tried everything and it would systemically nose the bullet to the very very far left of the chamber and fail to chamber. Ultimately, I suspect the breechface had been cut out of spec. I have never ran into this issue ever again.
With that said, you are better served trying factory ammo before just shipping the gun back. There are too many variables in reloads to consider your issue as a firearm issue until these variables can be removed from the possibilities.
What you are dealing with concerning this gun and its issue are simply a part of thw hobby of firearms. Resolving these issues is where true learning of gunsmithing and reloading comes from. if you don't at least try factory ammo and just ship it off to glock, I suspect they will test fire it after a month or so of backlog, determine it functions just fine with factory amm and in oem, and ship it back to you.
Except the fact that when you customize a gun an the ammo the burden of it functioning reliably is on you. Then take a scientific approach to resolve these issues and learn what works and what doesn't. This is how true expertese is achieved.
First I'll reply, in brief to the previous posts. It makes sense to use a high power factory loads for testing. Buffalo Bore, not DT, is the only commercial ammo I have seen that really equals my desired load for woods carry. Also, this issue of G20 high power load jamming is easily found while internet searching, even instances with Buffalo bore 180 gr JHP. I don't have a case gauge, I measure with calipers and have checked by dropping into the Lonewolf barrel.
I was looking for ammo at Sportsmans so I looked at a box of Federal SD JHP, 180 gr. $30/20 for an advertised 1030 fps. The same bullet in 40SW loading advertised at 1000 fps, 30 fps difference [LOL]. Even if I did find cheaper test ammo to check other aspects of the brass, it would not tell me about the high power question. I did take caliper measurements of the cases at the store (again) and compared to mine, looked good. If I can find cheaper commercial ammo, even weaker I will try it out.
Gun has a good amount of liquid lube I apply at the start of the session. I would rather run a gun wetter than drier.
Jams are nose up and mostly to the left. I was concerned about pressure increases as well, that's why I reduced my max for the following tests.
At the range today, gun in stock form. Fired six test groups of 10 each. First four strings had magazines loaded to 14 but shot only 10 for chronograph strings. Last 2 strings had magazines loaded to 10 shots. I had two different loads.
Load 1)
9.3 grains Longshot (reduced max for testing with shorter COL)
CCI 350 primers
1.250 COL (reduced from previous attempts)
New Starline brass
Montana gold CMJ 180 gr
Load 2)
8.8 grains Longshot
WIN WLP primers
1.250 COL
New Starline brass
Montana gold CMJ 180 gr
Wife shot the first four strings, 2 handed firm grip (10 of 14 fired).
String 1) Magazine A, Load 1, 1238 fps , Jam on shots 2, 4, and 6
String 2) Magazine B, Load 1, 1232 fps, No jams
String 3) Magazine A, Load 2, 1180 fps, Jam on shot 3
String 4) Magazine B, Load 2, 1142 fps, No jams
I shot strings 5 and 6 (10 of 10 fired)
String 5) Magazine B, Load 2, 1183 fps, No jams (5 shots 2 handed, 5 shots single handed)
String 6) Magazine B, Load 1, 1233 fps, Jam on shots 4 and 5 (10 shots single handed)
So it seems magazine A may have an issue and possibly magazine B with the higher velocity loads as well. Load 1 (the hotter at this test) was considerably less than the 1330 fps I had been using earlier. I'll likely go back to that loading with the 1.250 COL and test magazine B further.
So the question in my mind is to still send it back. Currently waiting on Gun Genie to get more in stock. Either way seems as if magazine A has some issue and maybe due a warranty.
Oh by the way. At the end of the day I noticed the chronograph had been hit. Nicked the back sensor and bent the metal back. Wife had a couple of shots hit low so figured it had to be her. Almost a really bad day.
Are you having issues when using the factory barrel?
This entire thread has been shooting with the stock barrel.
I had another thread for the Lone Wolf barrel but I am wanting to get this issue sorted out, in complete stock form, before tackling that issue.
Have you tried using the barrel as a case gauge to see if your ammo drops in and drops out?
Anothert thing to try is to have another shooter fire the gun I've seen people that swear up and down that limp wristing isn't an issue and someone else fires it.and the problem goes away . Plastic guns are typically more prone to this because the frame has some give in it . Your wrists shouldn't break over under recoil the pivot point should mostly be your shoulders.
Have you tried using the barrel as a case gauge to see if your ammo drops in and drops out?
Yes, I have used the Lone wolf and stock barrels as a case gauge.
Anothert thing to try is to have another shooter fire the gun I've seen people that swear up and down that limp wristing isn't an issue and someone else fires it and the problem goes away . Plastic guns are typically more prone to this because the frame has some give in it . Your wrists shouldn't break over under recoil the pivot point should mostly be your shoulders.
Is that an offer :), just kidding.
I think one handed my wrist probably broke a few times. I guess I could limit my testing to two handed for the time being.
Is that an offer :), just kidding.
Some thing could be arranged depending on when and where .
Lots of us shoot pistols every Wednesday afternoon/evening in Pueblo West...
Thanks for the offers. I have a lot going on right now, hopefully I can take you up on it after muzzleloader season.
I have an OD G20 and I shoot it one handed with hot reloads and have never had one FTF or FTE or any hickup, I would have it checked out and probably switch back to the stock spring and send it in to glock, I love my Glock I shoot hot reloads and DT 200 gr rounds.
Been really busy, got my elk with black powder (335 gr REAL home cast) and have been getting my 12 year old daughter ready for Pronghorn season but I digress.
After discussing with my dealer and he with Gun Genie they agreed to take it back. I got the new one and have tried a few magazines. I can say I'm convinced there was an issue with the first gun and or magazines but there is still a jam issue, though not near as bad. Here are the results:
180 gr Montana Gold CMJ
new starline brass
WIN WLP primers
1.250 COL
9.3 grains Longshot
Avg velocity for all shots was around 1240 fps, so these are hot but not full power.
New Glock 20sf and new magazines, completely stock set up. Two handed grip, normal firm grip. In other words I wasn't trying to hold it really tight.
Each magazine was loaded with 14 rounds I fired 4 sets of full magazines
with mag A
set 1 -- no jam
set 2 -- no jam
set 3 -- one jam shot 7
set 4 -- no jam
1 out of 56 shots jammed
with mag B
set 1 -- one jam shot 9
set 2 -- one jam shot 7
set 3 -- one jam shot 7
set 4 -- one jam shot 7
4 out of 56 shots jammed
All jams were nose up. So this is a great improvement before I was getting multiple jams per magazine. But now it seems to be a magazine issue during middle of the loading, I have read of this problems other are having.
The common denominator in all this is your reloads sorry to say.
Try some factory ammo with a completely stock gun.
It will be the only way to rule out the gun at this point.
Hoser,
That is what I was planning on doing. I actually contacted Swampfox to order some of their high power 180 gr ammo. After exchanging a few emails and my recipes, Mike suggested I try my load with a different primer (CCI 300). I have used 350's as well and he thinks the magnum primers are providing a bigger pulse that may be contributing to the problem. The WLP's are hotter than 300's, based on my results. In his experience he thinks 1 out of 10 -15 Glocks have this issue and it's related to slide velocity at heavy loading. I have a similar thread on Glock talk where Mike posts under Mudrush. I loaded up 4 magazines worth and I hope to try this weekend. I shoot at Frontier Sportsmans (Fountain) if you'd like to go out sometime.
Tried with stock spring and 22# spring
Half the loads were with 180 gr XTP and half with Montana Gold 180 gr CMJ. All 1.250" COL
CCI 300 primers
9.8 gr Long shot
Average (overall) velocity about 1290 fps (XTP were slightly higher average, probably due to longer bullet seating deeper)
One magazine was noticeably worse at jamming than the other but both had jams (same type as before) regardless of spring weight. Both bullet types jammed. These jams are not favoring the left side as the previous pistol.
As an interesting side note this load produced more noticeable Glock smiles than similar velocity with CI 350 primers with lower corresponding powder charge.
Well I guess the next test is to use some of Mike's ammo (Swampfox) to rule out my hand loads then I would guess +10 mag springs if those don't work.
Anybody have a 10+ spring magazine I can borrow?
Should I try stretching the magazine springs in mine?
Hoser pm sent.
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