.30 Caliber failure to feed

[w2ec]

I'm attempting to fire my new 1920 Commercial 30 caliber for the first time, after complete cleaning and examination of course.

I'm using Winchester factory loads, 93 grain FMJ. I lock the toggle back with an empty magazine inserted, then remove and re-insert the magazine charged with 5 rounds. I release the toggle and the first round feeds perfectly. I then fire the first round, but the second round fails to feed into the chamber. Instead the cartridge is tipped upward so the nose jams into the top of the chamber. I attempted this 5 times and had the same result each time, first round fires, second round jams.

I proceeded to analyze the problem on the bench with some dummy rounds and have concluded that the toggle/breech is not moving fully to the rear on recoil. If I pull the toggle completely back so the breech face passes behind the cartridge rim in the magazine and release it, the cartridge feeds fine. But if I pull the toggle only part way back, just prior to the point where it would clear the rim of the top cartridge, and then release it, the friction of the bottom of the breech pushing on the top of the cartridge starts feeding the cartridge forward, but it is also applying pressure to the top rear of the cartridge just forward of the rim, so the cartridge is tipping upwards as it moves forward, and it jams exactly like it does during live fire.

So my question is, what would prevent the toggle/breech from retracting fully on recoil? The action itself is nice and smooth, no binding when operated by hand, it retracts freely and when released snaps forward with plenty of force. I would think that the Winchester factory 93 grain ammo should be plenty powerful enough to fully cycle the action, but it just doesn't seem to work, at least not to the point where it cycles the action fully rearward.

I've included two pictures, the first is of the feed failure, with the cartridge tipped up, and the second attempts to show the breech face where it is pressing the cartridge down just before the rim, causing the cartridge to tip and jam.

I'm confident that if the toggle/breech moved fully rearward past the cartridge rim on firing, the pistol would function fine.

Any ideas/suggestions for a Luger newbie?

[Mauser720]

w2ec -

Hopefully someone on the Forum can tell you if the ammo you are using is sufficient to properly operate the toggle.

Another possible cause of failure to feed is frequently a substandard magazine. Everyone seems to recommend a MecGar brand magazine if you have one or can find one. A magazine with a weak spring can also cause the malfunction you have described.

Another easy possibility is that the grooves on the toggle, breech block, frame, and reciever might simply be too dry to function properly. Ensure you have enough oil on these parts that need to slide over each other easily, etc.

Please let us know what you find out since this is how we all learn.

Mauser720 - Ron

[policeluger]

Is the chamber rough and/or pitted, deos it need to be polished a bit?

[PhilOhio]

Once you have determined that a locked magazine will raise a round high enough for the bolt's lower lip to pick it up, it must do so with each successive round, if they are fed into the same position quickly enough and if the bolt has moved backward far enough. You already know this is possible, because it feeds the first round when hand cycled.

There are only a few common problem areas, with Lugers or anything else.

Closely fitted magazine followers and dents in mag bodies can keep the mag spring from pushing up the follower and raising cartridges fast enough. It has to be really fast with a Luger. Any little bit of grit can make it do exactly what you are experiencing. It's tough to take a Luger mag apart, but you can hold the follower button all the way down while you use a cleaning rod and patch to thoroughly clean the walls of the mag body with solvent. Clean it again with a dry patch. Then put some oil in, to lubricate the follower and get more grit out. Then clean and dry it yet again. A dry and unlubricated magazine is less likely to attract grit and jam. Satisfy yourself that the follower travels freely under full spring pressure. It should be difficult to hold the button down. And be sure your ammunition is clean and lint free.

Although less likely recently, there is still some weak ammunition floating around, "lawyer engineered ammo", I call it. It goes bang, but not with enough recoil to cycle a stiff Luger action or to blow up any dangerous junk gun and trigger a frivolous liability suit. Only after you have eliminated all possible problems with the gun can you focus on weak ammo as a possible cause.

You may think the action is free and smooth enough, but you may be mistaken. Use Three-in-One or any good gun oil to fully lubricate everything that moves and slides; grooves and rails of the grip frame and barrel extension, all toggle parts and their grooves in the barrel extension, spring and linkage, etc.

Examine the mainspring (without removing it) and see if you can make a good guess as to whether it looks like it may have been kinked, fiddled, or replaced with something too stiff, intended for a different model Luger. As a last resort, maybe a Luger expert could check this for you.

Here is where it can be useful to be a reloader. You can fine tune bullet weight and powder charge to be certain you are getting enough recoil to operate this or any other semiauto action.

While all semiauto pistols are affected by the sort of things I mentioned, the Luger seems to be especially sensitive, because it is so well made, tightly fitted, and has a rather violent high-speed action cycle. If everything isn't just right, it doesn't work.

I recently had the same problem you describe, and most of it related to a very slight bit of dry grittiness in the magazine body. After that was removed, rounds rose fast enough to be picked up.

[w2ec]

My thanks for all the very helpful comments on my problem.

I am going to focus on the magazine as I do recall it seemed stiff and somewhat jerky although not much worse than the mags for my other older personal semi-autos (mostly 1911's in various calibers) which all work fine in those guns, so I didn't do anything with this mag to slick it up. However as this is my first Luger and I'm still learning about them I did not take into account the cycle speed of the action as pointed out by PhilOhio. I can see how my thought that the breech wasn't moving rearward enough, could very easily actually be the fact that it did move fully rearward, but has started its forward movement before a weak/sticky magazine can feed the next cartridge fully up. Can't wait to get off duty so I can get home and clean the mag up. I'll also relube the pistol itself and make sure it is well oiled. We don't oil our duty guns much, we use modern grease on our Glocks and Sigs and I lubed my Luger the same way, light coatings of grease only on friction bearing points. I'll strip the grease and redo it fully with oil as suggested.

I do have a couple Mec-Gar mags on order, but until they arrive all I have to work with is the single original mag that came with the Luger.

I'll post my progress later.

[w2ec]

I received two new Mec-Gar mags yesterday and immediately went out to test them. I have the same exact problem, failure to feed a second round.

So, now going the possibly weak ammo route, I loaded up 5 rounds using Accurate Arms powder AA#5 loaded near max (according to the manual) which the manual indicates should be 1300fps out of a 6" barrel.

Let me preface this by saying I chronoed ammo from my only box of 30 luger, WW Super-X (which I believe is supposed to be 1220 fps) and it actually gave me a 1048fps average out of my 3-7/8" barrel, with one round at 981 and one round at 1080, the rest were in the 1020-1050 range.

My reloads, that I expected to be 1200 fps or more, averaged 1080, with a high of 1095 and a low of 1075. I used my original magazine and the first three rounds functioned successfully, with a failure to feed on the fourth round, which was the round chronoed at 1075. Also, firing the final round out of a mag fails to result in the action locking open on any of the three mags. But when cycled by hand, the action locks back perfectly. So it does appear to be a weak ammo situation not fully operating the action and it appears that I am going to have to up the load to well over 1100 fps. Since my AA#5 load is already near recommended max and it isn't making 1100 out of my barrel, I'll need to find a different load. I used AA#5 since I have lots of it, but I have other powder to try as well.

There seems to be a big velocity drop from a 6" to a 4" (3-7/8 really) barrel if the AA manual and WW specs are to be believed.

Anyone have any pet 30 luger loads they'd like to share that function well out of their 3-7/8" barrel Lugers?

[davjed]

I reload for an 8" .30 barrel and use Unique for a slower burn down the longer barrel. For my shorter 3 7/8" 9mm barrel I use Bullseye for a quicker burn in a short barrel. I seem to feel it cycle slower with the Unique. Perhaps a quicker burn rate would suit better in your short barreled Luger. Just my 0.02.

[Freischütz]

The pistol's outside is nice and clean so I assume the inside is equally well cared for.

7.65 Par is usually a reliable feeder. I have only had failures like those of your pictures when using underpowered ammunition. The minimum load with my pistol is 4.5 gr of Unique and an 94 gr cast bullet. 4.2 gr produced results like yours.

I only use handloads and don't know how powerful the factory W-W cartridges are. I know Fiocchi has a reputation for underloaded 7.65 Par ammo.

How old is your ammo? I once fired some very clean looking Winchester 7.63 Mauser ammo that was post-war. It looked great, the box looked like new, and every round failed to work the bolt of my C96. That pistol wound function reliably with 1,100 fps loads.

[w2ec]

Originally Posted by Freischütz

The pistol's outside is nice and clean so I assume the inside is equally well cared for.

Yes, the pistol is nice and clean inside as well, chamber well polished with no binding of the cartridge, action is smooth with no binding. At this point I'm pretty convinced it is a weak ammo situation. I ordered a Wolff light weight (36#) mainspring to try but it hasn't arrived yet.

The WW ammo appears to be pretty new, and I just received two boxs of the Fiocci (JSP, not FMJ) which I will try tonight. I also loaded up some rounds from the fired WW brass in .1 grain increments, I will attempt to function fire one round at a time until I find a load that will work the action to the point it successfully locks open on the empty mag. I will of course be checking for pressure signs as I go up in powder charge.

Thanks for all the helpful pointers on this forum!

[PhilOhio]

W2ec,

You are approaching this trouble shooting in a good, orderly way. My bet is that the lighter Wolff mainspring will solve your problems.

When you have a pistol for which such springs are not available, you can modify or make them from scratch. In the case of your Luger, you could remove the original spring (tricky) and put it away, buy a replacement, clip one coil, and see how that works. If necessary, remove a bit more until it works reliably with a cross section of modern ammo, or your favorite load. That's assuming recoil energy was the issue, and in this case I think it is.

I've been through this a few times, and have just done it once more, finishing yesterday. I have a mint post-war commercial Mauser HSc, an Interarms import. They are excellent and beautifully crafted pistols, but have an Internet reputation as "jam-o-matics". Why? Mauser made a few compromises on totally wrong recoil springs and didn't get the magazine follower design quite right.

I set my gun up to use both the original .380 ACP barrel and also a Mauser .32 ACP barrel.

I made my own stronger replacement magazine springs, heat treated them, and slightly modified the followers.

I then designed, wound, and heat treated three different recoil springs from two different (lighter) sizes of music wire. What Mauser had done was like putting a ten-ton dump truck spring on a VW Beatle.

After testing, I am now confident that the pistol can be trusted as a carry weapon, which was the point of the exercise...total reliability. ...which is not too common for an HSc, but should be.

The point of saying all this is to encourage some of the newer Luger people out there, to believe that most, if not all, of these functional reliability problems can be overcome. I'm only getting back into it after a lapse of many years. But my observation is that, although they have a reliability reputation somewhat like the HSc, most of that is just because they are so well made and closely fitted, and consequently they are very demanding on ammunition that is uniform, of high quality, and tuned to the dynamics of this stiff, high speed action. In my opinion, getting a fine old Luger to really run right, reliably, is worth a serious and methodical effort.

[w2ec]

Some progress has been made!

My Wolff 36# mainspring arrived today so my first step was to replace the original with the Wolff. This Wolff spring is a good 1" longer than the original I replaced. Also, just operating it by hand, it feels tighter/stronger than the original. I then fired 5 rounds (each single loaded in a mag) of the factory WW Super-X 93gr FMJ. Again, not one round locked the toggle back and the velocity was still in the 1050fps range. Not only that, but some of the rounds either didn't extract and eject or stovepiped. I really think this new Wolff spring is quite a bit stronger than the original. I then did the same with the Fiocchi JSP. Those 5 rounds also failed to lock the toggle back and and two failed to extract/eject. The toggle was closed tightly back over the fired rounds. The velocity of the Fiocchi ammo was in the 1060 fps range.

So now I moved on to my reloads. My first try was AA#5 and a 90 grain XTP .308 (not the .309) bullet. I used 5.8 grains, 5.9 and 6.0. None of these loads locked the slide back and average velocities ran 1048, 1062 and 1078 respectively. A few of these either remained in the chamber or stovepiped. Next I tried a slower powder, AA#7 with the same bullet at 7.1, 7.2 and 7.3 grains. Success! These rounds extracted perfectly when fired and every one locked the slide back. 7.1 grains gave 1119 fps, 7.2 = 1131 and 7.3 = 1145 fps. So it does seem like 1100 fps is the magic number for my Luger. It doesn't look like AA#5 will do for me as 6.0 grains is up at recommended max and still over 20 fps slow for the magic 1100fps.

There were no signs of pressure buildup on any of these loads.

Next I am going to try Unique, as I see many recommendations for this powder.

The main thing is I now know my Luger can function correctly once I get rounds reasonably over 1100fps. Now to work up a good consistent reliable load above 1100fps without any pressure signs. It was a good feeling to have the pistol functioning in the semi-auto mode, just like it should!

[Sieger]

Dear w2ec:

Let's solve this problem right now.

Hugh is definately on the right track!

Remove the Wolff Spring and put it away (hopefully, forever). Replace it with the original spring.

Load the following please.

With your Winchester brass and round nose 93 grain bullets, the final OAL of the loaded cartridge must be 1.173 inches, as shorter will contribute to jaming.

Medium slow powder is best for any Luger load, 9mm or 7.65mm. For me, Alliant Power Pistol at about 5.4 to 5.6 grains is an advanced target load (three touching out of three at 25 yards). Load a full magazine of 8 cartridges, as they shouldn't jam now.

Sieger

The jam you have shown us in the photos can be caused by too weak of ammo, or, too strong of ammo, as in the later instance, the breach block recoils faster than the mag spring's ability to properly deliver the next cartridge in line. You should be shooting from the Meg-Gar mags youv'e purchased.