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Old May 7, 2010, 10:52 PM   #1
philster
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How to stop clip feed probs and jams

I have a Hi-Point C9 (compact 9mm), and am having probs with rounds jamming while feeding from the clip. Actually, clips - two 10 rd and a 7 rd.

I figure that there are a set of common issues with this kind of thing in any semiautomatic. For instance, it appears that the clip lips play a very important part in how high the primer end of the cartridge sits and at what angle it lies in the top of the clip. All three are relatively new, and I had problems from the start with flat point ammo.

Well, I tried modifying the lips by experimenting with slightly bending them in or out. That didn't seem to help, and I resolved that the flat points were really the issue. I finally shot them all up and replaced them with standard round nosed ammo (extremely hard to find these days, it took months). So I go out target shooting today, and the same problem.

I could ask Hi-Point to replace them (and they would), but I figure I could have the same problem. I'd really prefer to know how to position the lips for optimum jam-free feeding for myself. Is there a rule of thumb to follow for measuring how far the round should sit at the top of the clip and the correct angle? Would slightly chamfering the lower lip of the chamber be something to try? I'd really appreciate any advice.
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Old May 7, 2010, 10:56 PM   #2
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For starters, I'd consider loading your magazines with ball ammunition and see if that helps with the feeding and reliability. Then see how well some hollow points feed in the gun. I wouldn't load your magazine with wadcutters.
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Old May 8, 2010, 12:28 AM   #3
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I don't have a Hi-Point, but I can make lots of guesses. Why did you think there was a problem with the magazine? The release point is important (where the round is free of the lips), as is the spring pressure. Does it jam more on the first round or the last round? Does it jam when you cycle by hand? If not, I would suspect weak springs. Can you take a closeup pictures of the parts and the jam?

Keep in mind that as the nose is sliding up into the chamber, the head of the cartridge is sliding up the breech face. A rough spot around the firing pin hole or the extractor, for example, could cause the round to go nose up.


If you can duplicate the problem by hand cycling, troubleshooting will be safer with dummy rounds. Here's one way to make dummy rounds:

1. Pull the bullets out of some of the ammo you're having trouble with. You will need one of these: http://www.midwayusa.com/viewproduct...tnumber=215517
2. Discard the powder, use your gun to pop the primers.
3. Drill an 1/8" hole in the side of each empty case.
4. Tap the bullets back into the cases until they're the exact same length as the ammo you didn't take apart.
5. Squirt hot glue or epoxy in the hole so the bullet can't get pushed further in when you're testing the gun.
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Old May 8, 2010, 09:42 AM   #4
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DSA1115 - I did try ball ammo, same prob, I was surprised.

LaserSpot - when I was originally using FP's I made a possibly incorrect assumption that the prob was with the clip, and started tweaking the lips.

As for spring pressure, I've read where lots of folks load the clip 1 rd short until clips are broken in and that helps. However, jams occur throughout the feed at various points.

Some jams leave a round free of the clip but crossed in the chamber, but most are (you'll have to help me with terminology) when the receiver feed tang picks up the back of the round and the nose of the bullet tips down and sticks against the face of the chamber just below the opening. The first case requires dropping the clip and retracting the receiver to dump the round out. The second is resolved by just releasing/re-inserting the clip manually cycling a single rd.

I've also noticed when loading the clip that the top rd nose position varies. Sometimes the nose ends lay nice and flat against each other, then at other times there is slight separation as if they're pivoting slightly on the rim at the primer end. Pressing down on the top rd and releasing results in a slightly different angle. I don't know if this makes a difference or not.

As for weak springs, these clips have hardly been used - less than 200 rds each. I'd also read where most Hi-Point owners had fewer probs after the clips had cycled several times (springs originally too stiff).

I can take pictures, and will the next time I go to the range. I'll check for a rough spot around the firing pin hole or the extractor.

I haven't tried continuous hand cycling, but will. Wouldn't it be easier to use those snap-caps for this purpose? Maybe more expensive, but less trouble and more easily available if they are a match for size.
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Old May 8, 2010, 11:39 AM   #5
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Quote:
Some jams leave a round free of the clip but crossed in the chamber, but most are (you'll have to help me with terminology) when the receiver feed tang picks up the back of the round and the nose of the bullet tips down and sticks against the face of the chamber just below the opening.
Is there rough spot right where the bullet nose is stopping?


Quote:
As for weak springs, these clips have hardly been used - less than 200 rds each. I'd also read where most Hi-Point owners had fewer probs after the clips had cycled several times (springs originally too stiff).
That is a possibility; if the spring is too stiff, that could cause the rounds to nose down when they're stripped from the magazine.


Quote:
I've also noticed when loading the clip that the top rd nose position varies. Sometimes the nose ends lay nice and flat against each other, then at other times there is slight separation as if they're pivoting slightly on the rim at the primer end. Pressing down on the top rd and releasing results in a slightly different angle. I don't know if this makes a difference or not.
It does sound like a problem with the magazine. I think you should ask Hi-Point to replace them; they might have had a bad batch or something.


Quote:
I haven't tried continuous hand cycling, but will. Wouldn't it be easier to use those snap-caps for this purpose? Maybe more expensive, but less trouble and more easily available if they are a match for size.
No, snap-caps are for dry firing. They're too light and they're made of plastic; it would be meaningless if they don't feed from the magazine. You could use Action Proving Dummies: http://www.brownells.com/.aspx/sid=1...uger__per_10__
If you can reproduce the jams by hand cycling, you could save a lot of ammo and trips to the range. I would hate to see you waste $200 in ammo in a vain attempt to fix a $150 gun.

Also, could it be limp-wrist malfunctions? Is it less likely to jam with a really tight two-hand grip?
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Old May 9, 2010, 10:13 AM   #6
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I'll check for rough spots where indicated, I'm going to try short loading the clips minus 1 rd, and also will pick up the action dummies (pretty cool tool). Is there any special technique to cycling the action to more closely simulate a firing? I typically grip the receiver firmly with one hand across the top, then push the pistol body underneath it quickly and firmly forward and release the receiver to let it return and chamber a rd.

I've never heard of a limp-wrist malfunction, and don't know how that's supposed to contribute to jamming - please explain. I'm using a two-handed grip. I'm a lefty, and I rest the butt of the grip in my right hand. Ham of my right thumb pressed against my left little finger with right fingers wrapped up and around the back of my left hand.

Hi-Point will replace all of the clips free of charge, I just wanted to understand the mechanics of what causes these problems. I was also concerned that the replacements may have the same issues. If it's anything besides the spring, I thought it should be something I could fix myself and save the aggravation of sending them out and back - living without any clips for however long.
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Old May 9, 2010, 11:41 AM   #7
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Quote:
also will pick up the action dummies (pretty cool tool).
Dummies are also useful for detecting a trigger flinch. Drop a few in your pocket along with some live ammo. Load the magazine while you look at the sky. When it goes click instead of bang, do the sights stay on target? If not, it's something you need to work on.


Quote:
I've never heard of a limp-wrist malfunction, and don't know how that's supposed to contribute to jamming - please explain.
Limp-wristing is a problem that some polymer-frame pistols have. This is because the frame isn't heavy enough to stay put while the heavier slide reciprocates. This results in the slide not going all the way back, so the cartridge doesn't have time time to rise completely, and the slide isn't returning as fast.


Quote:
Limp wristing is a term used to describe a phenomenon commonly encountered by semiautomatic pistol shooters, where the shooter's grip is not firm enough to hold the frame of the pistol steady while the bolt or slide of the pistol cycles. This condition often results in a failure to complete the operating cycle, properly termed a malfunction, but commonly (and incorrectly) termed a jam.

http://en.wikipedia.org/wiki/Limp_wristing
Try pushing with one hand while you pull the pistol toward you with the other hand. If the problem is limp-wristing, you may need a weaker recoil spring or stronger ammo.


Quote:
I thought it should be something I could fix myself and save the aggravation of sending them out and back
I'm in favor of trying to fix it yourself if you can do so safely. The worst that will happen is you learn something, but still have to send the gun in.
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Old May 10, 2010, 07:48 AM   #8
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Wow - a great article on limp wristing. The Hi-Point is a composite frame, a compact, and I'm shooting light load practice rds (115 gr). I don't understand what the article means by fast burning powder versus slow - "fast burning powders caused failures to increase, and medium and slow burning powders of the range suitable for the cartridge gave the best reliability." I will try a firmer grip using the method you suggested.

It seems like maybe slightly weakening the recoil spring may be something to consider. How is this typically done?

I got to thinking about it, and short loading the clip won't help because the jams occur at different places in the clip feed.
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Old May 10, 2010, 07:44 PM   #9
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I don't know of a good way to weaken the recoil spring. Wolff and other companies sell different rate springs for some pistols, but probably not for Hi-Point. Try a firmer grip and look for +P ammo. If a firmer grip helps, you could try an intentionally weak grip to confirm the problem. I still wouldn't rule out the magazine spring.

I would guess that loads with slower burning powder are more reliable because they produce more recoil. A significant part of recoil is due to high velocity gas leaving the barrel after the bullet. Even though the gas doesn't weigh much, it's moving at a much higher velocity than the bullet is.

When a slower powder is used, more powder can be put into the case without excessive pressure. Because it's slow burning, the pressure peaks later and is higher at the point when the bullet clears the barrel. So, a larger mass of propellant gas exiting at a higher velocity would give slightly more recoil to operate the slide.
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Old May 11, 2010, 08:40 PM   #10
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This is all great info - I really appreciate it. The Hi-Point C9 is +P rated. However, it's still pretty hard to find 9MM ammo of any kind, much less very specific loads. I don't know if the +P designation is related to the speed of the powder, or just the size of the load. There's lots of FP out there though! :barf: I'm shooting Winchester 115 gr. FMJ round nosed for target practice now. Other than a +P rating, how can you tell what the powder speed of any particular box of ammo is?
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Old May 11, 2010, 09:16 PM   #11
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+P means it's loaded to higher pressure so it will produce higher muzzle energy. It will be marked +P on the box and on the case head. I don't think there's any way to tell what powder it's loaded with unless you want to load your own.

You could buy some online if the local place doesn't have any: http://www.midwayusa.com/viewProduct...tNumber=997993
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Old May 12, 2010, 09:38 PM   #12
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OK, I have the dummies, and... !@#$! I must be doing something wrong in working the slide, but I don't know what it is. For some reason most of these don't release from the slide when retracted, like when a live rd is fired and ejected. Sure the rd is extracted from the chamber, but it stays attached at the rim and the next rd just tries to jam in with it. What's going on? I noticed that these dummies have NO primer inserted. Maybe the spent primer is required in the cartridge for the action to function normally?
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Old May 12, 2010, 09:47 PM   #13
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Just to see the differences between what I'm shooting and the +P you found (THANKS!):

Winchester
Muzzle Velocity: 1190 fps
Muzzle Energy: 362 ft. lbs.

Black Hills +P
Muzzle Velocity: 1300 fps
Muzzle Energy: 431 ft lbs

It appears that the muzzle energy difference is more than enough to change the way the slide retracts and the rds feed.
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Old May 12, 2010, 09:57 PM   #14
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Another thought - if the bullet is heavier (147 gr vs. 115), will that also increase recoil as there's more resistance against the burn?

Here's the defense ammo I bought:

Winchester Supreme Elite Ammunition 9mm Luger 147 Grain Bonded PDX1 JHP
Muzzle Velocity: 1000 fps
Muzzle Energy: 326 ft. lbs.
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Old May 12, 2010, 10:08 PM   #15
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Most guns have a seperate ejector, but I think yours uses the firing pin as the ejector. You will have to find a way to fill the primer pockets so the pin has something to hit against. Maybe hotglue?

Or, if you have a small pin punch, you could tap the spent primers out of fired cases and try to get them into the dummy rounds.

It's hard to say if heavier bullets are likely to be more reliable. You haven't ruled out problems with the magazine spring, feed ramp, etc... Feeding the dummy rounds may provide a clue.
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Old May 12, 2010, 10:13 PM   #16
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OK, for my last post I guess it does look like the numbers are going the wrong way on the PD rds to help me with jamming. If muzzle energy is the key indicator, then it looks like clip jams may even be worse.

As for the dummies, I figured it out - but I don't know how to work around it. The firing pin doesn't retract fully with the slide. As a normal spent rd is pulled back by the extractor tang's grip on the rim, the primer hits the end of the firing pin and this spins the casing outward through the port and free of the tang. Without a primer cap in place, this doesn't happen and the casing doesn't get pushed off of the extractor. Do I need to insert something in the primer hole to fix this?

It's a miracle I didn't break my firing pin by jamming another rd into the breach.
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Old May 13, 2010, 08:11 PM   #17
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You must have been typing when I hit Submit. See post #15
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Old May 14, 2010, 07:39 AM   #18
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JB Weld KwikSteel filled the primer holes nicely and the rds will eject properly. Now I need to take pics of the jams I'm getting, and the angles of the rds in the clips.
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Old May 14, 2010, 05:13 PM   #19
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Good idea; that's better than hot glue. So is it jamming the same way when you hand cycle rounds? If so, that probably rules out limp-wristing.

Does it make a difference if you pull the slide all the way back and let go, or if you hold onto the slide as it goes forward?
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Old May 16, 2010, 04:09 PM   #20
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Well, now that the dummies are right it doesn't seem to jam with round nosed ammo when hand cycling. However, I figure that I'm slowing down the action and almost trying to cause a jam if I hold onto the slide, so I've just been releasing it at the rear of the full retraction stroke.

I've attached my pics with comments. I would have put them in with the text, but forgot how to do that.

1RD in Clip - note the alignment of the rd casing with the clip, it's pretty much parallel without a lot of spring tension in the clip. Shown are both the dummy and JHP rds.

Note where the primer sits with respect to the edge of the clip. I guess I'll have to post another reply to get the rest of the images.
Attached Images
File Type: jpg DUMMY 1RD_B.JPG (76.4 KB, 35 views)
File Type: jpg JHP 1RD.JPG (63.3 KB, 33 views)
File Type: jpg PRIMER.JPG (63.8 KB, 31 views)
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Old May 16, 2010, 04:15 PM   #21
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Now look at the rd position with respect to the edge of the clip lips when it's fully loaded and under max spring tension - this is a 10 rd clip (I have two), but it's the same for the 7 rd standard clip. I'm showing both the dummy and JHP as the final rd in case you have probs distinguishing the clip lip edges from the cartridge casing.

The last pic is looking down into the clip when it's fully loaded. In this case, I kept pressing down and quickly releasing the rds in the clip until the last rd lined up with the clip lips again instead of being cocked at an angle, but this results in the gap you see at the bullet end of the cartridge between the last rd and the one underneath it.
Attached Images
File Type: jpg DUMMY FULL.JPG (50.6 KB, 23 views)
File Type: jpg JHP FULL CLIP.JPG (75.5 KB, 23 views)
File Type: jpg FULL CLIP RD GAP ALIGNED TO LIP.JPG (55.0 KB, 26 views)
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Old May 16, 2010, 05:10 PM   #22
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Lastly, here's a couple of pics of the slide face and the feed ramp into the chamber. I don't really know exactly what I'm looking at here, but the slide face seems OK to me - even if slightly scored vertically.

The feed ramp into the chamber seems a little strange, as it looks like the nose of the rds have been taking some squiggly diagonal line driving up the ramp from lower right to upper left.

The two different feed probs I've seen are where:

1) the slide moves forward and instead of catching the top rim of the cartridge (which may be sitting too low in the clip lips), seems to miss and slides over the rim and catches in the groove instead. This moves the cartridge forward with the rd nose angling up, but with the slide catching and stopping while resting on top of the rim instead of getting behind it and picking it up - and the nose jams in the chamber opening.

2) the nose of the rd is slanted downward (like when the clip is full), the slide picks up the back of the cartridge and moves it forward, but the nose hits the face of the feed ramp too low and stops, refusing to slide up into the chamber.

Lastly, a new problem when chambering the JHP rds - which I haven't tried at the range yet. In addition to them jamming (when hand cycling) more often against the face of the feed ramp with a full clip, they seem to have a little more difficulty sliding into the chamber. Once a rd is in the chamber, it sticks inside just enough that hand cycling an unfired rd won't remove it. The extractor tang slips off and leaves the rd in the chamber. I've had to use a pair of small long needle nosed pliers to put their tips in the rim and lever the rd backwards. I have no idea what'll happen when I actually fire one and it tries to eject.

My first (uninformed) take on what I've found is to maybe open up the clip lips ever so slightly near the bullet end of the rd. This should keep the bullet casing aligned with the top edge of the clip lips instead of angled down when the clip is full. This might keep the bullets from jamming into the bottom face of the feed ramp.

It seems I should also make sure that the rds in general (observing primer position at back edge of clip) are riding up high enough into the clip lips so that they get picked up properly by the tangs on the bottom of the slide face when it moves forward, instead of getting missed and ridden over.

Some light polishing might be in order for the feed ramp. The angle of what appears to be the bullet noses sliding upward into the chamber seems a little weird, but I don't really expect to try and change that - just maybe hand polish what's there.

As for the JHP rds in the chamber, I guess I'll need to fire one and find out what happens when it tries to eject. Maybe the blowback from firing will kick it out where hand cycling fails.

All of these are just my observations though, and I won't do anything until some folks have commented so I don't risk make it any worse. I'm looking forward to your advice.
Attached Images
File Type: jpg SLIDE FACE.JPG (114.6 KB, 32 views)
File Type: jpg CHAMBER3.JPG (110.6 KB, 31 views)
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Old May 16, 2010, 09:14 PM   #23
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It looks to me like the rounds aren't rising to the correct position, possibly because the follower is tilting inside the magazine. That would explain the nose-down jams. It could be caused by rought spots inside the magazine tube that the follower is catching on. It could also mean that the inside of the magazine is smooth, but has some kind of gummy film causing the follower to bind. It could mean that the spring is too weak.

Is it possible to remove the baseplate, spring and follower from the magazine tube? It may help to clean the inside of the tube with a bronze brush or a toothbrush and some Break Free CLP. The breech-face and feed ramp look rough; I would scrub them with a stiff brush and CLP too. A tiny square of 600 grit emery cloth glued to the eraser on an old pencil can be used to polish spots like that.

The problem with the round not extracting could be a dirty chamber; give it a good cleaning. This is a blow-back gun, so the only function the extractor provides when you fire it is to act as a pivot point for ejection.

The problem with the slide catching in the extractor groove could mean that the rounds aren't rising fast enough; the next round has only milliseconds to move into position for the slide to catch it. It could also be a limp-wristing type failure where the slide doesn't go back far enough to catch the rim.
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Old May 16, 2010, 10:20 PM   #24
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If I'm going to work on polishing the feed ramp and breech face, shouldn't I go ahead and remove the slide? Did you see anything strange about the squiggly diagonal track the bullets appear to be making up the feed ramp?

I've read some scary stuff about people polishing the feed ramp too much and making their problems worse. I want to be careful to avoid this. Some have mentioned using a dremel, but with the small soft felt pad at low RPM. Which would be more aggressive, the dremel as described or the 600 grit emory cloth on the pencil eraser? For that matter, how about just using a good typewriter eraser? They're considerably grittier and harder than a standard pencil eraser.

I think you can disassemble the clip, I'll take a look. Hey - isn't there also some sort of trick you can use with chalk powder or something to check for exact points of contact or wear spots in the feed?
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Old May 16, 2010, 11:04 PM   #25
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Take it apart and give everything a good cleaning first. I couldn't see the squiggly diagonal track.

Red polishing rouge is finer than 600 grit emery cloth. It should be pretty safe on a felt bit. Don't try to get all the tool marks out. Don't try beveling a new angle with a grinding stone. Also, if you have any plated or anodized parts, you don't want to wear through the surface coating.

You can check for contact points by blackening the feed ramp with candle soot, or a Sharpie, or by putting lipstick on tips of the bullets. Make up a story about why you need the lipstick.
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