Do you know the definition of quality?

[Sry0fcr]

The military’s set of specifications (mil-spec, get it?) is contained within the TDP (Technical Data Package). The TDP carries a lot of weight with you guys and for good reason. It’s just about the only published (even if it is proprietary) specification for manufacturing a “known quantity” carbine/rifle. It has become the defacto standard, not on its merit alone but because no other standard has been published. Does this mean that anything that does not meet the TDP specification is “low quality”? This seems to be the dominant view, and I would say that it’s wholly incorrect. Phillip Crosby defines quality as conformance to requirements, not goodness or elegance. Learn this definition and understand it.

If I were to order 12 DPMS carbines from a distributor and they send me 13 6920’s is this a non conformance? Absolutely. The distributor failed to meet the requirements of my P.O. despite me receiving “more” & “better”. Similarly, the military has certain requirements. For example 1:7 twist 4150 MIL-B-11595E chromed lined barrels, with a specific gas port size, & a notched barrel. The 1:7 twist is to stabilize M856 tracer rounds, and the 4150 barrels hold up better to sustained automatic firing, the gas port is sized to attain a cyclic rate of 700-950 RPM only with 5.56 NATO pressure ammunition and the notch is to mount a M203 grenade launcher.

Are your requirements similar?

Why do we demand the mil-spec when the “me-spec” is more applicable?

Do we know enough about the platform to make decision about which parts of the mil-spec can be deviated from and when?

My intent here is not to justify people’s purchase of “inferior” equipment, but to bring awareness of what quality actually is and the importance of being able to define requirements of the end user and to enable us to be “thinkers” not “followers”. If you’re able to determine your own requirements find something that meets those requirements then do so & be able to explain why you deviated. If not then buy the known quantity but admit that your opinion is unqualified. The truth is, while I appreciate the effort rob_s has put into The Chart, I think that he’s created a monster because people lack the knowledge to understand what they’re looking at (to be fair he tried to explain the features) or what quality is… much less how to achieve it. Some folks will balk at the idea that one of the key principles of quality is to cease dependence on inspection to achieve quality but it wouldn’t make it less true.

Randy B. - Quality Systems Analyst
ASQ Certified Quality Improvement Associate
ASQ Cetrified Quality Process Analyst pending
API/ISO Internal Quality Auditor

[TehLlama]

Being the offspring of quality engineers, it's simple for me to draw the most linear conclusion between the quality (correct matching and maintenance of tolerances and metallurgy in the parts of a weapon system) and the mean rounds between failure with all other variables controlled.

My requirements differ significantly in a few minor areas, but when looking at a reliable stock carbine there shouldn't be significant deviation from the TDP in regards to BCG, LPK, barrel materials and dimensions, or assembly steps such as pinning gas blocks and staking gas keys and castle nuts as needed.

There are ways to differ that do not hurt reliability (KAC's hydraulic pressed gas blocks, and castle nuts, as well as IWS Bolt on SR-15's come to mind; SS and CHF barrels that are not MIL spec, but outperform that spec in key areas), but cost savings measures leading to tangible deficits on very known quantity weapon systems will eventually become evident as weapons are shot enough.

[Wiggity]

Thank you for posting this. Too many people think that chart was sent directly from heaven.

[irockstar661]

Thank you as well. I am also in quality. In the aerospace manufacturing industry.

Sent from my LG-P999 using Tapatalk 2

[Grizzly16]

In your example the divergence from the order is a good thing, more high quality rifles than expected. Had they sent you 11 mini-14s then you are screwed.

Has any serious poster on this site ever argued with the fact that better than milspec for logical reasons is ok but worse than milspec is bad? The "it needs to be milspec" is usually preached at folks thinking a $1000 olympic arms rifle is just as good as a $1050 colt.

[rob_s]

Originally Posted by Sry0fcr

Why do we demand the mil-spec when the “me-spec” is more applicable?

I tend to view the "mil-spec" as similar to a building code, meaning it is the minimum basic standard and that there is certainly room for improvement. The problem is that many companies don't even meet the minimum standard and in turn charge the same, only slightly less-than, or even MORE than other companies that do meet, or come closer to meeting, the standard.

It sounds to me like you maybe understand the definition of "quality" but you maybe don't understand the spec, or how others choose to apply it to themselves or their recommendations for others. I don't think you'd find anyone here telling people to choose a Colt 6920 because it has a barrel notch but until the release of the 6720 very recently the 6920 was the only way to get the specs that are important for the majority of users (whether military, LE, or civilian) and so we accepted the notch because of that. Similarly, the twist rate issue may have been spec'd for one reason but it has a happy coincidence of also being better for the better performing defensive loads since those loads were often developed to work in the military spec guns.

Also, most people's "me-spec" is nothing more than "cheapest gun that appears to be an AR-pattern firearm I could find at the gun show". That's fine if people buy based solely on appearance and ignorance. In that case, I would like to sell each of them a "Ferrari".

[Safetyhit]

Originally Posted by Sry0fcr

The 1:7 twist is to stabilize M196 tracer rounds, and the 4150 barrels hold up better to sustained automatic firing, the gas port is sized to attain a cyclic rate of 700-950 RPM only with 5.56 NATO pressure ammunition and the notch is to mount a M203 grenade launcher.

Great questions overall and food for thought. But I was under the impression that the 1"x7" was implemented to better suit anything from 62gr M855 to 77gr, such as MOD 1 and so forth. Never heard it was geared for tracers, though they obviously have to be accommodated.

By the way, considering your credentials I thought you would be interested to know that your post was a quality one.

[militarymoron]

Originally Posted by Safetyhit

Great questions overall and food for thought. But I was under the impression that the 1"x7" was implemented to better suit anything from 62gr M855 to 77gr, such as MOD 1 and so forth. Never heard it was geared for tracers, though they obviously have to be accommodated.

IIRC, the 1x7" twist was developed to stabilize the longer M856 tracer, not the M196 (which is a 55gr tracer bullet). the Mk262 MOD 1 didn't come out until almost 20 years after the 1x7" twist was introduced in the M16A2.

back to the original post - good post, and i agree that it's important to understand both your needs and the specifications that something is manufactured to, if you're concerned about quality. but, without the in-depth understanding of what something like the TDP means, it's a convenient way for the new shooter or novice to ensure that the weapon he's purchasing has met SOME SORT of specification, minimal or not. it helps the new the purchaser who does not yet have the knowledge to recognize whether the weapon falls short of, or exceeds the TDP, to narrow the selection down.

[Sry0fcr]

Originally Posted by Grizzly16

In your example the divergence from the order is a good thing, more high quality rifles than expected. Had they sent you 11 mini-14s then you are screwed.

Then you'd be wrong. In QA, there is no good, better or worse, only meets requirements and doesn't meet requirements.

Originally Posted by rob_s

I tend to view the "mil-spec" as similar to a building code, meaning it is the minimum basic standard and that there is certainly room for improvement.

Can you quantify why it's the minimum standard other than it's existence?

Originally Posted by rob_s

It sounds to me like you maybe understand the definition of "quality" but you maybe don't understand the spec, or how others choose to apply it to themselves or their recommendations for others. I don't think you'd find anyone here telling people to choose a Colt 6920 because it has a barrel notch but until the release of the 6720 very recently the 6920 was the only way to get the specs that are important for the majority of users (whether military, LE, or civilian) and so we accepted the notch because of that. Similarly, the twist rate issue may have been spec'd for one reason but it has a happy coincidence of also being better for the better performing defensive loads since those loads were often developed to work in the military spec guns.

If there's two things I understand it's specs and the definition of quality. I'm questioning whether or not you and others actually understand the specs in the TDP and whether or not you've evaluated them to know if they meet your requirements?

Originally Posted by rob_s

Also, most people's "me-spec" is nothing more than "cheapest gun that appears to be an AR-pattern firearm I could find at the gun show". That's fine if people buy based solely on appearance and ignorance.

And what's wrong with that? If they're requirement is for a cool looking gun that's as cheap as possible a HK716 probably isn't the right answer is it?

[Grizzly16]

Originally Posted by Sry0fcr

Then you'd be wrong. In QA, there is no good, better or worse, only meets requirements and doesn't meet requirements.

Yes, in a clincal/iso9000 whatever blank standard you work in this is correct. In the real world I call getting something better than I ordered for the same price a good thing. Say I order a COLT 6920 and the box comes with 3 extra mags. That may be a QA failure to you but I don't mind that. But if I order a colt 6920 and get a dpms with non-chrome barrel that is both a QA failure and a problem for me.

In the world of m4c a company that exceeds the TDP's quality standards is a good thing. A company that doesn't even meet that level is a bad thing.

[Safetyhit]

Originally Posted by Sry0fcr

Can you quantify why it's the minimum standard other than it's existence?

Probably because it is a performance standard established around the round to which it applies, in this case a 5.56.

[Sry0fcr]

Originally Posted by Grizzly16

In the world of m4c a company that exceeds the TDP's quality standards is a good thing. A company that doesn't even meet that level is a bad thing.

Then perhaps the M4C world should become more than drones beating the TDP drum and learn to think for themselves?

Originally Posted by Safetyhit

Probably because it is a performance standard established around the round to which it applies, in this case a 5.56.

Then the answer to my question is, "No."?

[Safetyhit]

Originally Posted by Sry0fcr

Then the answer to my question is, "No."?

Sounds to me like you are looking to play games at this point. Have at it.

[militarymoron]

Originally Posted by Sry0fcr

Can you quantify why it's the minimum standard other than it's existence?

sure - in a nutshell, it's the minimum standard that the parts manufactured need to meet in dimensions, materials and testing to ensure parts interchangeability, life/durability, and performance etc. of the weapon as required by the military.

[Grizzly16]

Originally Posted by Sry0fcr

Then perhaps the M4C world should become more than drones beating the TDP drum and learn to think for themselves?

What posts are you referring to where a member of m4c derided a company that exceed the TDP quality standards?

[Sry0fcr]

Originally Posted by Safetyhit

Sounds to me like you are looking to play games at this point. Have at it.

I may be challenging dogma but I'm not playing games. It's a serious question. Is the TDP the minimum standard because it's the the "best" standard or because it's the only one published? Also, is it possible to build a "good" carbine that doesn't necessarily meet the TDP?

[Sry0fcr]

Originally Posted by Grizzly16

What posts are you referring to where a member of m4c derided a company that exceed the TDP quality standards?

None, but I have seen members deride a company that didn't meet the TDP specs for deviations that, truth be told are inconsequential for the intended purpose.

[Safetyhit]

Originally Posted by Sry0fcr

None, but I have seen members deride a company that didn't meet the TDP specs for deviations that, truth be told are inconsequential for the intended purpose.

I completely agree in context, but that doesn't deny the need for a military based standard or make it irrelevant to most. If you want to do so much thinking you can elaborate what deviations you feel would be sensible and why.

[militarymoron]

Originally Posted by Sry0fcr

And what's wrong with that? If they're requirement is for a cool looking gun that's as cheap as possible a HK716 probably isn't the right answer is it?

the problem is that the people looking at the cheapest cool looking gun still expect it to function/perform, and are surprised when it doesn't.

[C4IGrant]

As we all know, people use AR's for lots of things. Some of them include:

1. Target shooting
2. Hunting
3. Gun Games
4. Plinking
5. LE/MIL
6. Self Defense


In categories 1, 2, 3 and 4, the TDP has little to no relevance. Meaning that if your gun fails in some way, it really doesn't matter and is mostly an "inconvenience." So buy whatever you like that you believe will best fit your needs.

Categories 5 and 6 is a different type of animal. These guns might be saving someone’s life. So for them, we want a known standard to follow to ensure that every part fits, is reliable and can deliver a certain level of accuracy.

Now the question is, are their guns or parts that go above what the TDP calls for? I am sure there are some parts that will outlive a part built to the TDP standard. I am also sure that some people BELIEVE that something is better just because it fits their needs better, but it actually isn't better in any way (Carbine gas vs Middy Gas systems come to mind).

IMHO, there are few parts that have been verified (or at least tested) as being better than what the TDP calls out. Most of the "enhanced" parts are pretty much smoke and mirrors when you get right down to it.




C4