Magazine Measuring Procedure

[vluc]

Are you or are you not thinking the mag in the picture is legal?

With the mag crooked in the gauge it is clearly illegal. With the mag straight in the gauge it appears to be legal due to the rumored "No daylight" criteria. With the mag sitting in the gauge with some pressure applied it appears to be very legal. However, are you allow to apply pressure when measuring or not ?? If not, show me where this is documented !!

By the same token, show where it says you can? I think you are getting into a Clintonism of it depends on what "is" is.

If you were beat by another shooter and you found that they had to push and tug to make his/her mags fit into the gauge, would your response be the same as what you want to argue here?

I think your desire to have clarification has merit, though.

Edited September 6, 2010 by vluc

[L2450]

Are you or are you not thinking the mag in the picture is legal?

With the mag crooked in the gauge it is clearly illegal. With the mag straight in the gauge it appears to be legal due to the rumored "No daylight" criteria. With the mag sitting in the gauge with some pressure applied it appears to be very legal. However, are you allow to apply pressure when measuring or not ?? If not, show me where this is documented !!

Nick,

I used enough pressure to hold the mag and the gauge without slipping, anything more than that would be forcing the mag into the gauge. I also kept the basepad square to the bottom of the gauge. I did have calipers with me, you should have asked me to measure the magazine as shown in Appendix E1 of the rulebook.

You are free to send a query to John Amidon, Director of NROI, and ask the question on how to measure mags using the gauge. I would be very interested to read his reply in Front Sight.

Bud

[nwb01]

Are you or are you not thinking the mag in the picture is legal?

With the mag crooked in the gauge it is clearly illegal. With the mag straight in the gauge it appears to be legal due to the rumored "No daylight" criteria. With the mag sitting in the gauge with some pressure applied it appears to be very legal. However, are you allow to apply pressure when measuring or not ?? If not, show me where this is documented !!

By the same token, show where it says you can? I think you are getting into a Clintonism of it depends on what "is" is.

If you were beat by another shooter and you found that they had to push and tug to make his/her mags fit into the gauge, would your response be the same as what you want to argue here?.

Well, I am not arguing anything, just trying to clarify the process and not go by somebody's interpretation of the how it is to be done. If I wanted to go by interpretations I would shoot a different sport !

If someone had to "push and tug" their mag into the gauge to fit then who really cares. Shouldn't we give the competitor every possible opportunity to comply with the rules. I don't see how a couple of thousandths would give somebody an advantage. Believe me, if a rule was written the didn't allow it I would not be happy. For some reason, no WRITTEN rule on how to perform this procedure has turned up !!

Are you or are you not thinking the mag in the picture is legal?

With the mag crooked in the gauge it is clearly illegal. With the mag straight in the gauge it appears to be legal due to the rumored "No daylight" criteria. With the mag sitting in the gauge with some pressure applied it appears to be very legal. However, are you allow to apply pressure when measuring or not ?? If not, show me where this is documented !!

Nick,

I used enough pressure to hold the mag and the gauge without slipping, anything more than that would be forcing the mag into the gauge. I also kept the basepad square to the bottom of the gauge. I did have calipers with me, you should have asked me to measure the magazine as shown in Appendix E1 of the rulebook.

You are free to send a query to John Amidon, Director of NROI, and ask the question on how to measure mags using the gauge. I would be very interested to read his reply in Front Sight.

Bud

How do you know you cannot force it into the gauge ?? Do you have documentation that says this is not the correct way to use the gauge ?

John has already been queried.

Calipers would have not been the correct measurement tool to use, a height gauge would be more suitable in this application. You would have also need an instrument to ensure the magazine was truly perpendicular to the measuring surface.

[Flexmoney]

As Nik and others have said...

We have a ruling from 2008 that says to use the gauge.

We have a rule book from 2010 that shows a "procedure" (< that word used at the top of the page on E1)...

Ample room for confusion.

Seems like we still have some rulings on the books that are dated?

[Brazos Custom]

One thing to keep in mind is that almost every mag/basepad combo will have some play in it. The mag spring will have a tendency to push the magazine basepad out to its longest measurement. After you drop the magazine a bunch of times and disassemble/reassemble this slop gets a little bigger and if you are not allowed to compress the magazine spring/basepad at all you could get a situation where the magazine is legal at one point and then might not be later as it wears.

[Pat Miles]

One thing to keep in mind is that almost every mag/basepad combo will have some play in it. The mag spring will have a tendency to push the magazine basepad out to its longest measurement. After you drop the magazine a bunch of times and disassemble/reassemble this slop gets a little bigger and if you are not allowed to compress the magazine spring/basepad at all you could get a situation where the magazine is legal at one point and then might not be later as it wears.

I've often wondered about this situation. My 170 mags will fit the guage when pushed into it to collapse the mag spring. Not to try to imitate a lawyer and protract this discussion, but what might an RO do if i Popped the spring and follower out before handing the mag over to be measured. Measurement is from the back corner of the base pad to the back corner of the feed lips. Hmmm.

Pat

[Skydiver]

One thing to keep in mind is that almost every mag/basepad combo will have some play in it. The mag spring will have a tendency to push the magazine basepad out to its longest measurement. After you drop the magazine a bunch of times and disassemble/reassemble this slop gets a little bigger and if you are not allowed to compress the magazine spring/basepad at all you could get a situation where the magazine is legal at one point and then might not be later as it wears.

I've often wondered about this situation. My 170 mags will fit the guage when pushed into it to collapse the mag spring. Not to try to imitate a lawyer and protract this discussion, but what might an RO do if i Popped the spring and follower out before handing the mag over to be measured. Measurement is from the back corner of the base pad to the back corner of the feed lips. Hmmm.

Pat

Although the measurement point is from the back corner, the gauge supposedly goes to infinity... this thread was left abandoned when I posed the question to get people's thoughts about trimming feedlips and basepads: Magazine trimming and fitting the gauge

It seems like the NROI ruling overrides the rulebook, and the rulebook should have been updated.

I do think that it is a bit unfair that by mandating the use of the gauge, it also implicitly implies a limits on the maximum angle between the horizontal plane defined by the basepad and the plane defined by the feedlips. Imagine a new gun design a few years from now that has a more radical grip angle, and hence feed lips that point up even higher. The back of the mag from feed lips to basepad may be legal (based on the "measurement procedure" in the rulebook), but it won't fit in the gauge. As a visual try exaggerating the angles in the link I reference above even more.

[JThompson]

I say we do away with the gauge and the limit on length all together. Max capacity of say 18 etc or 28- 29 whatever, and call it a day. It would save an insane amount of money in mag tuning and the whole issue of SNL +1 +2 etc would be moot. Also, coming up with more minutia to figure what is legal and not.. X amount and no more and we don't care what the hell length your mags are. Not only that, but it might possibly bring back calibers which have been discarded for rounds that fit more into a pre defined space.

JT

Edited September 6, 2010 by JThompson

[SLM]

Where's the fun in that Jim??

[JThompson]

Where's the fun in that Jim??

Ya, imagine me wanted less rules .... Hmmm, Maybe it's because it would be one less thing for me to deal with as an RM.

JT

Edited September 6, 2010 by JThompson

[George Jones]

Ya, imagine me wanted less rules .... Hmmm, Maybe it's because it would be one less thing for me to deal with as an RM.

JT

Sometimes less rules = more RO work.

Counting rounds to 10 is already a challenge for some. Imagine having to count rounds on every stage for every mag in every gun up to "28-29 whatever".

[herky]

You would have to add an extra RO/round counter to every stage.

[JThompson]

Ya, imagine me wanted less rules .... Hmmm, Maybe it's because it would be one less thing for me to deal with as an RM.

JT

Sometimes less rules = more RO work.

Counting rounds to 10 is already a challenge for some. Imagine having to count rounds on every stage for every mag in every gun up to "28-29 whatever".

I thought about that George. I think it would be much less to deal with than the constant reset of count you get from 8 or 10 rounds. You know how many targets there are, so you just add 1 for any extra shots and when they get to X target you know they have fired X round and will need a mag change. If they don't then you call them on it and check to see how many rounds that mag will hold. In this case you would load to 28 or whatever and if it accepts another.....

I'm really not advocating this as a rules change.... It's more of a what if and have some discussion. Shotgun plugs work pretty well for limiting rounds. If a mag didn't accept more than X rounds then everything is cool. There are other issues with that as in how much force do you try to apply to load that last two rounds... and by doing so do you wreck a guys mag or springs. As I said, I think it's worth some discussion, but I'm asking people to think more than actually wanting this change.

JT

[rgkeller]

So we have an approved mechanism to check mag length and an rulebook procedure for measuring mag length that does not include the approved mechanism.

Seems like the NROI would be all over this.

[nwb01]

So we have an approved mechanism to check mag length and an rulebook procedure for measuring mag length that does not include the approved mechanism.

Seems like the NROI would be all over this.

One would think but it looks like it has been an issue since 2008 !

[nwb01]

One thing to keep in mind is that almost every mag/basepad combo will have some play in it. The mag spring will have a tendency to push the magazine basepad out to its longest measurement. After you drop the magazine a bunch of times and disassemble/reassemble this slop gets a little bigger and if you are not allowed to compress the magazine spring/basepad at all you could get a situation where the magazine is legal at one point and then might not be later as it wears.

It sure would be nice to get some clarification......... I wonder what the reaction of an RO would be if you handed them a mag with no follower or spring for measurement ??

[Paul B]

If you look at Appendix E-1 of the 2010 rules the measurement of a magazine is from the very back of the feed lips (there is no follower shown) to the longest portion of the basepad. It is not from a move-able follower. The diagram is very clear what is to be measured.

Then someone had to make a gauge. I have never seen a machinists drawing of the gauge, but the important dimension should have been the one in the above appendix. If Amidon or anyone else approved a gauge without a very oblique angle for the rest of the feed lips at the top of the magazine then they were wrong. The rest of the feed lips should never touch the gauge. If someone measured from the follower then they are also wrong. Whether it was Amidon's decision or not the gauge should fit the rules or change the rules.

Deciding on whether a person moves to open based on a certain amount of hand pressure on a mag in a gauge is simply not an objective way to check equipment.

Edited September 7, 2010 by Paul B

[bbbean]

It sure would be nice to get some clarification......... I wonder what the reaction of an RO would be if you handed them a mag with no follower or spring for measurement ??

I suspect the mag would be completely legal, as long as you ran it and all your other mags with no springs or followers. Welcome to Single Shot division.

[Rob Tompkins]

I use those same mags and extensions. Along with at least a thousand other shooters.They fit. Something not right here.

+1, mine passed, not even close at Area 8.

[nwb01]

It sure would be nice to get some clarification......... I wonder what the reaction of an RO would be if you handed them a mag with no follower or spring for measurement ??

I suspect the mag would be completely legal, as long as you ran it and all your other mags with no springs or followers. Welcome to Single Shot division.

How does one know this to be true ?? The picture in Appendix E1 shows no follower..... And there is no WRITTEN procedure on how to properly use the gauge. Hmmm....

[BayouSlide]

I wonder what the reaction of an RO would be if you handed them a mag with no follower or spring for measurement ??

The same as if you handed over your Production pistol minus the guide rod so it could make weight. Your pistol made weight/your mag made length. Now you get to use it in the configuration in which it passed

Curtis

Edited September 7, 2010 by BayouSlide

[nwb01]

I wonder what the reaction of an RO would be if you handed them a mag with no follower or spring for measurement ??

The same as if you handed over your Production pistol minus the guide rod so it could make weight. Your pistol made weight/your mag made length. Now you get to use it in the configuration in which it passed

Curtis

I understand what you are saying Curtis...

The guide rod is an integral part of the pistol and definitely has to be included when weighing. As for the magazine, are we not just measuring the tube/base pad length ?? The spring and follower can effect the length due to stacking up of manufacture tolerances and wear as Bob mentioned. But does this really affect the effective length of the magazine ??

[Flexmoney]

The spring and follower can effect the length due to stacking up of manufacture tolerances and wear as Bob mentioned. But does this really affect the effective length of the magazine ??

Obviously, it does.

If you take the slack out (which is how it would run during the match...under spring pressure) it will be longer.

What would be next if you didn't measure with the spring? Accordion-like base pads?

[Gary Stevens]

One thing to keep in mind is that almost every mag/basepad combo will have some play in it. The mag spring will have a tendency to push the magazine basepad out to its longest measurement. After you drop the magazine a bunch of times and disassemble/reassemble this slop gets a little bigger and if you are not allowed to compress the magazine spring/basepad at all you could get a situation where the magazine is legal at one point and then might not be later as it wears.

It sure would be nice to get some clarification......... I wonder what the reaction of an RO would be if you handed them a mag with no follower or spring for measurement ??

I would tell you that is not a magazine. It is at best a magazine tube, and a basepad.

When I measure a mag I compress the basepad as much as I reasonably can then measure. The gauge is already oversized, sometimes cutting it too close is cutting it too close, so to speak.

Gary

[z40acp]

I don't think he means force enough to compress anything but the slop in the base pad. In Single Stack,do they allow you to compress the spring on the back sight in order to fit the box?

Edited September 8, 2010 by z40acp