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View Full Version : 7 Rd. Vs. 8 Rd. Mags


coltsr
17th January 2005, 18:12
HI,
I have read that 8 round mags are not as reliable as 7 rounders. They say that the springs weaken faster. I have 4 Chip McCormick 8 round Match grade mags. My question is...What if you just load 6 or 7 rounds in them. Will they be just as reliable as the 7 rounders? And also, would the springs last just as long?
Coltsr

John
18th January 2005, 10:53
Good quality mags shouldn't have a problem and McCormick ones are some of the best. 8-rounders are the standard these days.

Rgds

SMMAssociates
18th January 2005, 11:09
I hope Tuner chimes in, but the real issue, I think, is that making an eight round magazine that's not too long to be convenient (and maybe even one that is too long) is asking the springs to do more than the basic Browning design intended.

The magazine spring has to provide a fairly constant tension on the ammo column when feeding the whole load, and that extra half inch (another coil or so of spring length) changes things quite a bit.

To do this, people have gone with shorter magazine followers and/or various different base designs. The results are always a compromise, as is the standard 7-round magazine anyway.

I don't think the springs "wear out" so much as just soften enough to not quite do what they're supposed to do. Again, the compromise "point" moves away from the design point. :eek:

I'm not any kind of an expert in this.... Just what I've seen "on the boards"....

(My Commander runs generic 7's with Tripp upgrade kits. Even if the Tripp thing is entirely hype - I'm not qualified to make a pronouncement - they seem to work as well as the magazines did originally, and let me burn off some stuff that the original magazine setups wouldn't feed. IOW, $8 for a replacement spring and follower isn't too terrible. Very stiff spring!)

N7CAV
18th January 2005, 11:10
I've had mizex results with 8rd mags, but stick with standard 7rd mags for several reasons. Mainly, the follower and spring setup on the 8rd mags are not as reliable. Government models are very forgiving when it comes to old magazine springs- Heavy reciol springs, commander, and smaller Officer's size models especially, are the most sensitive to weak springs because the action is so quick. If the last round jams frequently, I first suspect the follower is tipping. If the last round chambers and the slide doesn't lock on empty, it still look at the follower, then the mag spring.

Unless I'm at the range, I really avoid using 8rd magazines in carry. Just too much more pressure on the spring and more chance of failure. Using only 6 or 7 rounds in an 8rd mag isn't going to correct the problem.

1911Tuner
18th January 2005, 18:42
The problems with 8-round magazines in a nutshell...

Making room for 4 inches of ammo in a space designed for 3.5 means that
something has to be sacrificed. 8-round magazines require two such sacrifices.

One is in the length of the follower's rear leg. The leg keeps the follower stable, and this stability becomes more critical as the magazine gets closer to the last round...and the last round is most critical. The shortened followers
don't provide enough length for the required number of spring coils to hold it solidly against the inside of the magazine body. The result is a follower that
rocks forward, possibly causing the round to nose-dive into the ramp, and often causing the slidestop to fail to lock the slide on empty.

The other problem is with the spring. An extra half-inch of lost space requires that the number of spring coils be reduced in order to prevent
coil bind...which stresses the spring beyond its elastic limit and shortens its
useful life. In order to provide enough strength to correctly orient and feed that critical last round, the space between the coils must be increased...which usually results in only one coil to keep the follower stable.
Here is one of the main reasons that we see steel Devel-type followers doing damage to alloy frames.

An added problem is that the Devel follower is smooth on top. That little dimple on the original design follower is there for a very good reason. Removing it can and does bring on other problems, especially when the spring begins to tire out from use. It's all about that critical last round.

The Wilson-Rogers follower shares the last two problems with the Devel follower as used in the Powermags and Shooting Stars, even though it
doesn't share problem with stability.

Before anyone jumps me with: "My Wilson/McCormick/MecGar, etc etc
works perfectly"...I know. Some guns do okay with'em, and some don't...
but keep one thing in mind, and my experience bears this statement out.

That the gun is functioning is not proof that it's functioning correctly. It just
means that you got lucky...and your luck may not hold out.

An improperly functioning magazine can take the tension out of the extractor or even cause it to break. Whenever I see a pistol that loses extractor tension in just a few hundred rounds...the first thing that I look at is the magazine. Is the spring tension good? Does it have a dimple on the follower?

Cheers all!

Tuner

Noah Zark
23rd January 2005, 14:54
. . . An added problem is that the Devel follower is smooth on top. That little dimple on the original design follower is there for a very good reason. Removing it can and does bring on other problems, especially when the spring begins to tire out from use . . . Whenever I see a pistol that loses extractor tension in just a few hundred rounds...the first thing that I look at is the magazine. Is the spring tension good? Does it have a dimple on the follower?


Tuner:

Thanks much for posting your views on the 7 vs 8 rd. debate.

Regarding your statements alluding to the importance of the follower dimple, could you explain to me it's importance? What does it do for the last round?

Thanks again,

Noah

SMMAssociates
23rd January 2005, 15:09
Noah:

In case Tuner's out chasing his dog, there's a thread hereabouts called "Magazine Burps" that covers this.

Magazine Burps Thread (http://forum.m1911.org/showthread.php?t=1322)

You'll have to read down a ways to find the dimple stuff.

Regards,

Noah Zark
23rd January 2005, 15:20
Thank you, Stu. First time I've seen that, and I used to repair 1911A1s in the Marines as a 2111 in the early 70s.

Noah

1911Tuner
23rd January 2005, 15:31
Thanks for posting the link, Stu. I was just about to do it.

To clarify it a little further, the dimple is simply a physical barrier. You can demonstrate its function by loading one round in the mag, and pushing it straight forward slowly without downward pressure. You can feel the dimple
snag the cartridge rim, and stop the round from moving forward unless forced to.

Gonna be out of the loop for a few days guys...I'll be back in the thick of it soon, though. Ya'll take care.

Noah...Semper Fi!

"Gunny" Tuner :cool:

SMMAssociates
23rd January 2005, 15:55
Noah:

Tuner's our resident expert on stuff like this, although I don't want to slight anybody else 'cause this group is pretty sharp.

(Why they let me in, I'll never know.... :eek: )

Very interesting stuff! I'm kinda new to 1911's myself - I've been shooting for nearly 40 years, but not these, so I tend to read a lot. The dimple thing is downright funny if you don't know what's going on there, which kinda makes it "stick".

Tuner:

I hope nothing's wrong! I'm getting a CAT scan tomorrow, and probably some semi-minor surgery in a week or two, but nobody'll miss me :D as much as we'll miss you.

(A quick question - that silly Tac-Four's slide stop can be pushed out of the frame with finger pressure regardless of it's location v.s. the cutout. I'm waiting to hear from George at Para, but this ain't right? )

Regards,

Noah Zark
24th January 2005, 16:06
Stu:

I've read Tuner's informative posts on other boards as well as this one, but somehow missed the dimple explanation.

My 1911 experience started at age 9 in the early 60s, and continued through high school, service in the Marines as a Small Arms Repairman, through college in competition, and up to the present as a "plinker" when time allows. Presently in the stable there are a 60s Gold Cup, a 70 Series Electroless Nickel Govt, an 80 Series Combat Commander, an 80 Series Stainless Steel Govt Model, and a new to me but used Springfield MilSpec. Fed solely by McCormick Shooting Stars (psst: 8rd!).

Love 'em all.

Good luck with the CT and your pending surgery.

Gunny Tuner: Semper Fi, bro.

Thanks again to both of you.

Noah

SMMAssociates
24th January 2005, 16:31
Noah:

You're just a young 'un.... (How DO you spell that?).... I was old enough to buy a 1911 in the early 60's, if not carry it. (I wish I had - it'd be worth something now :) )

My first was a .32 revolver. Basically junk, but affordable. A Charter "Undercover" (.38 Spl) replaced that when sanity returned (and I had another $85). As I was doing rent-a-cop work, that quickly required a 6" S&W M19 - I'm kinda big so it didn't look too silly - and a 4" M10HB for plainclothes work. The Charter was my "backup" until I picked up a PPK/S. (I had to buy the 6" Magnum - most of S&W's production was going to the Military at the time, and that was all I could find. I'm still not sure how I was able to come up with the M10HB.)

When "Starsky & Hutch" were in vogue in the 70's, some of the City PD Detectives bought S&W M39's, and I saw one while visiting the Chief's Office one night and decided that I needed one. $125! Great plainclothes gun! It still shoots like brand new.

Fast forward until about two years ago. A friend of mine willed me a nice little Commander (which I never bothered to shoot until earlier this year), and I bought the Tac-Four last May. Minor problems with both (Wolf ammo crapped up the extractor in the Commander, and a sloppy gunsmith forced further repairs) got me deep into "how these things work".

It also got me to meet Tuner, which has been a ton of fun in itself, plus he does know his stuff. Just because he didn't come outside and wave to me and my bride when we drove through his town in 1975....

(I used to drive to Anderson SC two or three times a year from 1984 to about 1993, which puts you way too close to Tuner, too! Anderson's in the Atlanta area.)

And, Tuner, if you're around, your advice on the firing pin stop shape was right on for a buddy last week. On a Beretta! His son's stopped feeding reliably. Nothing worked - known-good magazines, etc. I looked at it and felt that the rear of the slide and the corresponding face on the hammer weren't "right". A bit more than the thickness of the paint and some fine polishing did the job. Joey's was almost square. His dad's (same gun) although quite square compared to my Commander, was a lot "softer". Worked....

The CT scan was this AM. I won't hear anything for a couple days. Probably will need a bit of surgery, but other than the doc wanting to be paid in advance, I'm not too concerned. :eek:

Regards,

John
24th January 2005, 23:20
CAT scan? Surgery? Nothing serious, I hope.

Wish you get well quickly Stu. And don't be sure we will not miss you.

Get well buddy, soon!

SMMAssociates
24th January 2005, 23:47
John:

Well, they didn't ask me to bring my own cat, at least :D .

I've been under the weather since mid-October, and generally screwed up (irritable bowel issues) for a lot longer.

We thought it was an infection (probably was initially), since much of the problem cleared up when I was taking an antibiotic, but as soon as I'd run out, about three days later, it'd come back. More antibiotics....

However, about three weeks ago it came back while I was still taking the antibiotic.

I got in to see my Gastroenterologist buddy ("digestive tract" specialist) and he recommended some X-Rays, which I did last Monday. Turned out that what was an "ignore it" thing in my stomach now appears to be about the size of an orange, and is impinging on my small intestine. It appears to be encapsulated or benign (the former means that the tumor's in a "bag" and is thus easily removed), but the pre-CAT-scan vote was to plan on yanking it.

The doc should get the CAT results Tuesday, and then we'll wake up my pet Surgeon and see what we can schedule. I'm going to try to talk him into arthroscopic (probably didn't spell that right) surgery - that's when they basically use a BIG needle rather than a big incision - but it's too soon to tell. I don't think they'll do that outpatient, but it's a quick recovery thing. The latter is serious cutting, but still shouldn't put me out of commission for more than a few days in terms of being in hospital or working. (I mostly telecommute anyway, and can work from my office or the recliner in the family room. The trick will be keeping the dog off my stitches....) I'll probably be off the range for a month, though.

Other than asking to be paid in advance, the doc's not too worried. Maybe I should send him an invite to come out and hold targets?

Regards,

John
24th January 2005, 23:55
Stu,

I hope that everything works out in the best possible way. Get well soon, and keep us posted on the outcome.