1911 tuners, first-I've-seen feeding oddity

[highxj]

Hey guys, I ran across a problem today that I haven't seen before....

I bought my wife a new Colt 5" Govt. 45 yesterday and we shook it out today. Ammo was primarily light 200 gr. SWC handloads, and a 20 round box of Hornady 230 gr. +P TAP.

Using the heavier loads, my wife experienced three failures to go into battery. In each case, the cartridge had chambered *ahead* of the extractor rather than sliding up under it during the feed cycle.

I've been building and shooting 1911's competitively for 25 years and have never seen this. This malfunction did not happen when I shot it, but I only put a few rounds of the +P stuff through it. The light target loads functioned perfectly. We were using the supplied Colt magazines with tapered feed lips.

The only theory I can come up with is this: My wife's lighter grip on the handgun combined with the stout +P loads allowed the slide to hit the rear stop violently enough to dislodge the top round in the mag. Then as the slide travels forward the barely contained top cartridge was pushed the rest of the way home by the front of the extractor. I haven't really taken the pistol and mags to examine if this is possible or not, but perhaps the tapered Colt feed lips would allow the cartridge to raise up enough for the round to go ahead of the extractor rather than under it if it were dislodged far enough forward under recoil.

Anybody else see this happen, or have any other ideas to throw out there? Thanks..

Dan

 

[1911Tuner]

It's a magazine problem, and probably the spring. An overly heavy recoil spring is also a contributor sometimes.

 

[Cemetery21]

Your theory sounds reasonable, Dan.
And, as you know from competing, if the recoil spring was light enough to cycle the wad loads, the +P was probably hammering the frame pretty solidly, which would come closer to inducing the inertia feed you saw. And, it may happen more when the mag is near empty since the spring pressure is reduced. New, tight mag springs will help by holding a little more friction on the rounds (in case you were using some older mags).

edit; Tuner types faster and is usually spot on.

 

[Baldy]

That's what happen to me one time when I listen to a kitchen table gunsmith. He talked me into a 14lb recoil spring and it done the same as yours. Changed back to the 16lb spring and the gun run just fine.

 

[highxj]

Yep, those loads were really whippin' the little gals wrists around. I seriously doubt it would ever happen to me......but it's her pistol so I need to run this little hiccup down.

1911Tuner, the pistol was box stock with the factory recoil spring and brand new factory mags. I don't care for overly heavy recoil springs either and don't generally go over 16 with full house .45 loads.

In all honesty the vast majority of my shooting has been steel shooting and Action Pistol using light loads and springs with very light recoil. Different things come into play when limp wristing with defense loads, which is why I haven't seen some of these malfunctions.

I'd really like to see this happen on a high speed video to find out exactly what it looks like. I locked the slide back and inserted a loaded mag (dummies), and pushed to top round as far forward as I could before it was released and eased the slide forward. The rim was still below the extractor hook, so my initial idea doesn't quite fit. Unless the round is actually being fully released by inertia and the slide starts forward before the next round has risen far enough to engage the breechface.

I suspect different mags would cure it and that's the next step I'll take, thanks for the replies.....

 

[rbernie]

Magazines with wadcutter feed lips (straight in the back with a big flare out front) release the round abruptly, and my experience has been that if the pistol's timing isn't 'just so' then these magazines can cause the round to jump in front of the extractor. The tapered feed lip magazines seem to not have this sort of issue (since they don't release the round in one fell swoop, so to speak), so sometimes switching magazines to the 'older' tapered lip design is all that is needed.

Weak magazine springs can also be a culprit, as 'Tuner suggested, because they can allow the round to 'pop' forward down the feed lips faster than the slide is moving, when the breechface smacks the base of the round. A stronger spring plants the round against the feed lips more firmly and helps keep it in time with the slide. If you don't want to buy into a new tapered lip magazine, maybe trying a 11lb/in Wolff spring would be a good idea.

 

[1911Tuner]

If he's got the OEM COlt magazine, it probably has the tapered "hybrid" type lips. The spring is the likely suspect. Wolff 11 pound/7 round spring will probably fix it.

If it doesn't, the feed lips themselves could be out of spec...too wide or even sprung.

The top of the follower should have a tiny bump on it. If somebody has filed it off...there's where the bug nests if it's always the last round that jumps. You can get a replacement from Check-Mate Industries.

 

[Jim K]

Was it the last round in the magazine and does the magazine follower have a "hump" in the middle? Some magazine makers eliminate the "pimple" thinking to improve smoothness, but there is a reason for it. When the slide comes forward and hits the case head, the cartridge tries to jump forward before the slide catches up with it. That puts the case ahead of the extractor. The "pimple" keeps the round from jumping.

Jim

 

[highxj]

Jim, they do have the bump in the follower...but these malfunctions happened in the middle of the mag.

 

[1911Tuner]

Then it's either a weak mag spring, or just a bad magazine. Sprung, or out of spec feed lips.
It could also be that the little speed bump on the follower is worn. That can happen. It wasn't a problem back in the dark ages when they hardened the followers, but it's a definite possibility in this enlightened age.

 

[Jim K]

Just curious, Tuner, but did you ever check out the feed lips of a GI mag vs those of a "new and improved" type. The GI mag lips allow the round to come up in an even and controlled manner. The new kind are made to let the gun handle short rounds with short or HP bullets and hold the round longer, then suddenly release it. I believe in using the new mags only for short OAL rounds, and stick to the old type for standard length. What do you think.

Jim

 

[Rail Driver]

If the mag is new, the mag spring could be binding inside the magazine body, causing loose rounds in the middle of the mag. Even something as small as a tiny burr that you might not notice when loading or unloading the mag could cause strange things to happen when firing.

 

[1911Tuner]

Sure have, Jim. If you'll look at the Colt OEM 7-round sticks, you'll notice that the lip design is a cross between the full-tapered USGI "Hardball" and the new ones with parallel lips and early, abrupt release point...which I refer to as "Wadcutter" magazines.

The timed release point of these "hybrid" magazines is a bit later than the wadcutter design, and a little less abrupt...and still allows for the gradual rise of the rear of the cartridge. I can't remember how many feed problems that I've "fixed" by simply handing the owner a few hybrid magazines equipped with Wolff 11-pound springs. The most recent was a new 5-inch Para Ordnance that the owner was ready to take a hammer to. I arranged for him to come with me to the range, and when he hit the 500 round mark without a single stoppage, he was mystified.

 

[bbuddtec]

Wouldn't the slide back hit be lighter if it was limped?

 

[bradph]

1911tuner..... do you favor the hybrid feed lips for hollow points and/or ammunition with a relatively short overall length (compared to FMJ that is).. or do you prefer wadcutter feed lips for shooting hollow points and/or ammo with short OAL.

I ask because a few folks have reported live rounds in the pile of brass when mixing hollow points with hybrid feed lips. Not often, but on occasion. Could be their gun or a bad magazine, or course.

Thanks!

 

[1911Tuner]

brad...Live rounds among the brass is most often a magazine spring problem, but can happen if the feed ramp is located too far forward of the magazine, or at the wrong angle.
Most often...with a spring issue...it's the next to last round that escapes when the slide hits the frame, then feeds the last round.

I like the hybrid design for all ammunition except that loaded with the short-nosed SWC bullets.

 

[bradph]

Thank you 1911Tuner!

I still remember that time you called me on the phone, when I needed some Norinco advice.... and the time you helped me with advice for my dog (you suspected she was gulping air when she drank, causing some health issues... took your advice, changed her behavior a bit, health issues never came back).

Thanks again,
Brad


ps: wish Checkmate would put a 11lb-type of spring in their 8-round, flush fit hybrids. If I had to guess, I'd say it is closer to 9. Just guessing though....

 

[1911Tuner]

Check-Mate has been busy, brad. They threw in the towel on flush-fit 8 round magazines, and are making an extended 8-rounder now, with a false slam pad to cover the extension. They're able to use a long enough spring and they've added a skirt to the Shooting Star follower for stability. They've also contracted with Wolff for the springs, and my test examples have done very well. They're available in the parallel and the hybrid lip design...blue or stainless.

They've also started making the full-tapered "Hardball" type magazine for public consumption...blue or stainless...7-round only. They're also available with the Heavy-Duty spring...which is the Wolff 11-pound number. For strictly hardball ammo, they're probably the best game in town, while the "Hybrid" will work well with hardball...hollowpoints of 1.210 inch OAL or greater...and the Hensley & Gibbs #68 SWC from OALs of 1.235-1.250 inch.

Of course, they also make the early/abrupt release "Wadcutter" type magazines for SWC bullets with a shorter OAL.

I worked with them in developing a gauge for the late release GI Hardball magazines, and from all reports...it's been successful. When they first reissued the design, they were having some trouble in locating the final release point consistently, and the gauge corrected it. My 15 minutes of fame, I guess. No money from it, but I do get to be a beta tester for their magazines, so it's all good.

 

[1911Tuner]

For a visual...Here's the comparison of the feed lips. On the left is the Hybrid design. On the right is the Wadcutter. Note the slightly later, less abrupt release point of the Hybrid.

The 2nd photo shows the difference in cartridge presentation at approximately the release point...placing the round closer to the extractor at the point of final release and reducing the distance that it has to "jump" so the extractor can pick it up. This rise also gives the round a straighter shot at the chamber.

 

[bradph]

1911Tuner,

I've a handful of both the flush fit and extended 8-round Checkmate hybrids in front of me... the springs sure look the same to me, diameter, number of coils, length. I could be missing something though.

One of the reasons I asked the original question, is that I noticed Federal's HST and Speer's Gold Dot rounds have OAL's around 1.209 - 1.208. So I though they would do better with wadcutter magazines. Compared to Remington's Golden Sabers that fall around 1.237, they are midgets.

Good to know you are working with Checkmate. Another reason to buy/use their stuff.

Thanks again,
Brad

 

[1911Tuner]

Give Check Mate a call. They've upgraded to stronger springs in the last 2-3 months.

 

[Jim K]

Thanks for all that info, Tuner. Some folks don't seem to realize how important that magazine is; they will spend bucks on feed ramps and all kinds of modifications, while using the same poorly made magazines.

Jim

 

[bradph]

Double thank you... great information!
Brad

 

[1911Tuner]

Amen, Jim...and the one feature that they really seem to miss is that silly little speed bump on the follower. They never stop to consider why it was put there to begin with.

The "Wadcutter" magazine works fine for what it was designed for. Namely...reduced power SWCs.
When the power and recoil forces go up...they often fall flat on their faces. The .45 caliber 1911 pistol isn't a smoothly cycling pistol. It's a fairly violent beast, and the magazine has to deal with all that slam-bang while maintaining control of every round. The last round is most critical because it has the least spring tension bearing on it. Doesn't take a rocket scientist to figure out that the magazine can use all the help it can get. That's what that bump is for.

 

[1911Tuner]

Whew! Got the dogs all tended to, and have a little time on my hands...so I thought I'd expound a little on the "Hybrid" feed lip design.

I first noticed the change in the late 70s in the magazines that came with Colt pistols. A little research revealed that it was a Colt redesign. Up to that point, the magazines that they included with their pistols were the GI Hardball type, and very likely left over from the anticipated government contract that never materialized in the late 40s.

Studying the design, and comparing it with a few GI magazines that I had on hand which had been modified by AMU armorers and Bullseye smiths to feed the Hensley & Gibbs #68 bullet, I found that the release point was nearly identical.

So, it appears that Colt took an old modification a step further and split the difference, designing a magazine that would provide reliable feeding with long hardball and short SWC and hollowpoint ammo...and it worked.

Their three main vendors...Check Mate...Metalform...and OKAY Industries make the magazines to Colt's specs, but only Check Mate makes them for public consumption., Sometimes, if you can catch Metalform with a small overrun...before the Colt logo is roll-marked on the bases...you can get them to sell to you in bulk orders. They don't normally have more than 15 or 20 on hand, though.

As an aside, Check Mate provided government contract magazines from late Vietnam era until just prior to the 1911 being phased out. I can't remember the CAGE code on the floorplates off the top of my head, but most of the genuine GI magazines found at gun shows are these...or at least they were. Beware of counterfeit Check Mate magazines. I haven't seen any real ones on exhibitors' tables in a good many years, and suspect that the surplus supply has long since dried up.