DSA semi auto selector problem (FULL-AUTO???)

[Bubba30]

I have had a problem with my DSA semi auto selector. I got one, put the thing in a STG and stupid me went of shooting without testing. Imagine my surprise when pulling the trigger once, more than one bullet came out. After thinking about it for a minute I decided to do what any other idiot would do and pulled trigger one more time, empting the magazine and walked away with a grin.

Yes I fixed the problem by filling in the indent with weld and then remilled it shallower, looks like a real hack job too.

Anyways have other people had this problem? was I supposed to change the trigger also or some other part I dont get it.

[ September 09, 2001: Message edited by: gary.jeter ]

[Wadman]

A semi selector has a tang on it to prevent the selector from rotating all the way down to the full auto position. Your rifle went auto on the normal semi position?

================================================== ========

But it worked okay with the old selector installed? That's pretty odd. In theory, the semi selector doesn't have a cutout that allows you to pull the trigger all the way back. So somehow the sear is letting go of the hammer after the carrier passes. This sort of contradicts the theory that a hammer riding the bolt won't have enough energy to set off the primer.

[This message has been edited by Wadman (edited February 07, 2001).]

[Bubba30]

Yes my selector has a tang, and yes the event happend in what should have been the normal semi auto area. The problem was the notch in the selector was way too deep, identical to the depth on the full auto selector.

Am I the only one who has had this problem or just the only one who even bothered to buy a semi auto only selector.

[Frontsight!]

Looks like I'll be sending off for one of those DSA selectors soon.

[Bubba30]

Sure it happend, Im sitting here with a spare STG lower and it does the same thing. Here is how you can run the test to. Just pull the selector all the way out and press the hammer down as you keep the trigger pulled back, the hammer doesnt tripp anything and goes right back up. This is same process as what happend to mine. The entire process in a working rifle is uncontrolled but did work for a string of 5 not sure what would happen after that. Heck maybe I fucked something up when I built it?

[Bubba30]

Hmmm? I swear it.. If it wern't so I would have not felt so guilty and did all the butcher work to the darned thing to make it legal. There is supposed to be a FN get together Ill show the guys there.

[Bruce Allen]

Bubba30. You are correct. As a matter of fact any FAL lower with an original selector placed in the auto position will allow the hammer to function freely.

BARLEY POP - You are right on. You (and I) know without the safety sear in place the hammer will merely ride the bolt carrier down after the first shot USUALLY not causing a discharge as the hammer is not able to directly strike the firing pin.

We all tried it just to see if it would work.
It don't.

Bubba30 - Let's say just for arguements sake your FAL actually went full auto. The case then is you have an extremely unsafe weapon that could fire a cartridge without the bolt and carrier being in full battery and that would destroy the weapon at least and some of you at worst.

My suggestion:
1. If this "story" is just that, go away quietly an come back later in an adult manner.
2. If it is true get the weapon repaired before you hurt the rifle, yourself and/or get in trouble.

[This message has been edited by Bruce Allen (edited February 07, 2001).]

[Bubba30]

Hey I didnt mean to upset you and yes Im just presenting the facts, as far as I can tell the rifle is built correctly and I have fixed the problem with the selector. I Well give it a workout and test it to see if is a fluke, that is what I was wondering about.

[Frontsight!]

Of course I was kidding when I said "I want one of those" but seriously, Bru is right...it could go off without being fully into battery.

My STG does the same thing that everyone's does on FA. It fires once...then you have to pull the charging knob, cocking the hammer again, but ejecting an unfired round in the process.

[BigOne]

I take it none of you read the post I gave to the last case of this that was presented. I notice it isn't still on the board as we seem to be running very few threads at a time here.

I don't really want to go through it all again.

In a nutshell. I am a former Cdn Forces Armourer. The FN will, under certain conditions, slam fire. We tried it and interchanged parts and tried it again during Mil testing. It can happen.

Secondly the safety sear is just that, and NOT a full auto part. It is standard in semi auto only FN's

The information related to Mil parts only. I have no personal experience with US made parts but can only assume if they are made to spec, nothing would change.

If Admin can dig up my previous response it might help sort this out.

Good luck.

[Bubba30]

Ah... finialy some support. Yes I think this is what happend I will dig the gun out tommorrow and look for crude buildup in hammer area.

[BigOne]

Bubba30. What you might want to do is check the length of the trigger return plunger. There are two lengths available, one for semi auto only guns and one for select fire. The longer, semi auto only one does not allow the trigger to go back far enough to use the extra depth of the full auto position on the selector. This plunger in conjunction with the depth of the semi auto slot in the selector prevent the trigger from being able to be pulled far enough to prevent it from engaging the sear, thus keeping the gun semi auto.

The safety sear is designed to catch the hammers forward travel. It is disengaged by the bolt carrier just before the firearm goes into battery. This allows the hammer to engage into the fire control system without the momenteum it would have had had it been allowed to make contact without this interuption in movement. This prevents it from overrunning the fire control group and firing the firearm. The momentary pause, as the hammer overruns is enough to allow the bolt carrier to take the bolt into battery before the hammer follows along, thus allowing the hammer to strike the firing pin.

I would recommend ensuring the selector notch is the correct semi auto depth and get the right plunger for the trigger return for semi auto. Also be sure that any US parts in the lower are to Mil spec for dimension. You will then be as safe from this situation as you can be with an FN that has no safety sear.

Good luck.

[Bruce Allen]

Originally posted by BigOne:
Bubba30. ...The safety sear is designed to catch the hammers forward travel. It is disengaged by the bolt carrier just before the firearm goes into battery. This allows the hammer to engage into the fire control system without the momenteum it would have had had it been allowed to make contact without this interuption in movement. This prevents it from overrunning the fire control group and firing the firearm. The momentary pause, as the hammer overruns is enough to allow the bolt carrier to take the bolt into battery before the hammer follows along, thus allowing the hammer to strike the firing pin....

BigOne - You obviously have the knowledge and practical experience here that I do not.

Please help my education here.

I as I understand it the safety sear function is to provide a built in "hesitation", if you will, into the firing sequence of the FAL. As you put it so the hammer does not "overrun" the bolt carrier group. I assume we are on the same wave lenght here.

OK. If the safety sear is for semi auto rifles only then why is the presence of the safety sear needed for correct full auto function?
In line with that question - if the hammer is held in check by the primary sear in semi auto fire, why would the safety sear be needed at all. It would not be redundant in operation but would not be utilized at all, would it??

Third question - Aren't all the STG58's originally select fire weapons? If that is correct then aren't the lower receiver trigger group parts as we receive them still capable of full auto function.
If your contention that the plunger is the primary reason for full auto fire is correct then why don't more "kits" fire full auto?

No flame intended here, I am seeking to expand my knowledge some.

[Charmedlyfe]

Actually, the ejector blocks are different in the semi and select FALs. The safety sear was exactly that....a safety feature. Another case of the BATF not knowing their D*ck from a toothpick.

[Enquiring Minds]

Another case of the BATF not knowing their D*ck from a toothpick.
OK, without commenting on either the genitalia of ATF Tech Branch employees, or the old-womanish motives behind the U.S. 1934 NFA, let me humbly attempt to correct some topic drift and ambiguously written or read sentences. (NOTE: post this in the Gunsmithing forum and maybe more gunsmiths will chime in.)

OK. If the safety sear is for semi auto rifles only then why is the presence of the safety sear needed for correct full auto function?
Correction: It's not semi-auto rifles ONLY, it's semi-auto-only RIFLES, i.e. NON-select-fire rifles, setup to function only as semi-auto. The safety sear appears in both select-fire and (ORIGINAL, non-US, and G-series) semi-only rifles.

And YES, the safety sear IS NECESSARY for reliable, properly-timed, and in-battery full-auto sequencing and firing. It's obviously only an "insurance" feature in semi-auto mode, i.e. in case the trigger sear doesn't scoot forward on its oval pivot hole by the time the bolt+carrier comes ALL the way back and far enough forward to uncover the hammer OR the momentum/bounce/overrun issues mentioned above--not likely, unless...? Perhaps BigOne or other RKI will elaborate on this.

The select-fire selector, in the full-auto position, allows the few extra degrees of trigger travel that pivots the other (trigger) sear out of the way such that it cannot latch the hammer, leaving only the safety sear to latch the hammer.

So what this comes down to is: the original un-adulterated FN-FAL design, even in its SEMI-AUTO-ONLY configuration, is EASILY CONVERTIBLE to full-auto, since the only difference is a few extra degrees of TRIGGER TRAVEL. This few extra degrees can be obtained by some minor filing on the selector and the trigger return spring plunger. This delights full-auto enthusiasts but annoys the ATF, and you know who's going to win that standoff.

Uneducated guesses on Bubba30's delayed hammer symptoms:
1) DSA selector notch depth was BETWEEN full and semi spec., causing poor sear-nose-to-hammer-notch fit, barely engaging, and getting jolted loose by bolt carrier slamming home????
2) Brass shavings from an aggressive extractor, monkeying up the fire control assembly...?

[Bruce Allen]

...Originally posted by Enquiring Minds: OK. If the safety sear is for semi auto rifles only then why is the presence of the safety sear needed for correct full auto function?
Correction: It's not semi-auto rifles ONLY, it's semi-auto-only RIFLES, i.e. NON-select-fire rifles, setup to function only as semi-auto....[/B]

Enquiring Minds - My question was from the first post of BigOne, and I quote - "Secondly the safety sear is just that, and NOT a full auto part. It is standard in semi auto only FN's"..

Some of what BigOne posted is contrary to what I have heard and read and studied about on my own about the function of the FAL.

"The select-fire selector, in the full-auto position, allows the few extra
degrees of trigger travel that pivots the ther (trigger) sear out of the way such that it cannot latch the hammer, leaving only the safety sear to latch the hammer. [/B]

Yes, your point, sir?

So what this comes down to is: the original un-adulterated FN-FAL design, even in its SEMI-AUTO-ONLY configuration, is EASILY CONVERTIBLE to full-auto, since the only difference is a few extra degrees of TRIGGER TRAVEL. This few extra degrees can be obtained by some minor filing on the selector
and the trigger return spring plunger. This delights full-auto enthusiasts but annoys the ATF, and you know who's going to win that standoff. [/B]

I believe you are simply wrong here.

I refer back to my original question that asked about that:
"Third question - Aren't all the STG58's originally select fire weapons? If that is correct then aren't the lower receiver trigger group parts as we receive them still capable of full auto function. If your contention that the plunger is the primary reason for full auto fire is correct then why don't more "kits" fire full auto?"

If your information were true then EVERY lower receiver that had original full auto capability would function again as a select fire weapon as soon as it were assembled.

They do not, though. So...aren't we back to the safety sear, and of course the correct ejector block that would accomodate it.

[Enquiring Minds]

OOPS, did I add more ambiguity? My entire discussion assumes the PRESENCE of a safety sear, which presumes the ejector block and upper rcvr cuts to accommodate it. From prior posts I was led to believe that all semi-auto-only FALs/inch guns intended for NON-U.S. markets still had the safety sear in place. "Easily convertible" is strictly a U.S. hangup, like so many fun things.

Some of what BigOne posted is contrary to what I have heard and read and studied about on my own about the function of the FAL.
His statement is ambiguous, easily misread. I think what BigOne meant was the safety sear is not found ONLY in select-fire weps, and that even in semi-mode and in semi-only rifles, the safety sear DOES actively toggle in/out of its hammer notch--it is NOT deactivated by any position of the selector.

... Yes, your point, sir?
Just that the safety sear is really the "disconnector", and thus the essential link for CONTROLLED full-auto functioning. It is redundant in semi-auto as proven by millions(?) of American semi-only FALs that function just fine without it.

I believe you are simply wrong here.
Not at all, but I guess instead of "original un-adulterated" I should have said "non-US semi-only guns with safety sear in place". Then it makes sense, as any RKI or ATF Techie will confirm, and it is truly a "kitchen table" conversion in that config.

p.s. The StG kit lowers ARE full auto capable, including the ej block and safety sear, but since the US uppers don't have the relief cutout, you wouldn't be able to close and latch the two halves of the rifle. (You may also find the importer has ground back the ridge on the left side of the bolt carrier which "trips" the safety sear.)

SUMMATION: No proper FAL full-auto withOUT a safety sear, never said otherwise, wouldn't be prudent, no new taxes, free beer for everyone... who's your Dubya?

[BigOne]

Yes, I can see my information was a little mis-interperated, sorry wasn't as clear as I should have been.

I was trying to make the point that the safety sear is in both semi auto only AND select fire weapons and is not only found in select fire weapons.

In the semi auto only weapon the safety sear is there to prevent the possibility of the hammer over running the fire control group and is designed to prevent the firearm from firing until the forward movement of the bolt carrier has ensured the bolt is in battery. It also prevents damage to the engagement surfaces of the fire control group by letting the hammer come in contract much more gently than it would if the safety sear did not pause the forward motion, thereby removing the momenteum that the hammer had built up traveling forward under spring pressure.

In an extremely worn or dirty weapon, even a semi auto only, the hammer may not properly engage the fire control group which, without the safety sear in place, could result in the weapon firing out of battery. You all understand what a disaster that would be.

Basically if one recognizes the "safety sear" by it's true name. Then you understand the whole purpose for it being in the original design. This said, it is true that this same "safety sear" is employed in the full auto firing cycle, but the primary reason for it being in the weapon is to prevent premature firing.

I have only seen a few STG58's all of which have been standard design, incorporating the safety sear. I have, on hand, semi auto only FN's of both inch and metric design from various countries, all of which have provision for the safety sear. I also have several select fire versions, all, of course, with safety sear provision. Also, if one consults "THE FN RIFLE" by Blake Stevens, the operation of the "safety sear" is fairly well covered there.

Other than US made parts, I have never seen or heard of a Military FN not being equipped with the provision for the safety sear in the ejector block.

Anyway. I do hope this clears up what I had meant in my previous posts.

As far as being able to make a semi auto into a full auto. Yeah, it's real easy. But I won't get into that here as no one in todays "politically correct" society needs to know.

The FN was, and still is a great design. The interchangeability and convertability of parts between semi only and select fire was one of the reasons the aromouers loved them. If you found yourself with a bench load of busted guns, you could always get some running, really fast, and back on the line before having to actually "fix" weapons, with new pieces.

[Bruce Allen]

Thank you BigOne and Enquiring Minds.

I am going to assume my study about the STG58 is mostly typical. When I picked up the first complete lower receiver and observed it's function and saw the last selector position allowed full unrestricted hammer function I went OOOOOH mama, look at this!!

Then you wonder how it can be sold in this configuration. That led to the further study.
Given the same conditions of thing most men will come to very similar conclusions.

I can see we are in the same "wave length" here.

See there all of you guys - it is possible to have a discussion without flaming one another.

[Enquiring Minds]

Thanks BigOne and Bruce,

For the continuing education on the world's most user-friendly, and armorer-friendly(?), .30 cal MBR.

... It also prevents damage to the engagement surfaces of the fire control group by letting the hammer come in contract much more gently than it would if the safety sear did not pause the forward motion, thereby removing the momenteum that the hammer had built up traveling forward under spring pressure.

Ah so... excellent point. I can see there's a LOT more force involved under fire vs. hand-cycling. (Or to put it another way, even though I don't live in a "cult compound", the ATF is still endangering my life with unwise actions! )

Thanks to your explanation, I have a much clearer appreciation for the "safety deficit" we silly Americans are operating under without the safety sear. Perhaps when you get a chance, you might distill some of your armorer's experiece into an FAQ on the "care and feeding" of fire-control parts, what to inspect for, how to "re-sharpen", etc.

I can see we are in the same "wave length" here... it is possible to have a discussion without flaming one another.
Indeed it is possible. Though our patience is tried at times by lawyers and shooters of ComBloc weapons , civility is usually its own reward.

[This message has been edited by Enquiring Minds (edited February 10, 2001).]

[W.E.G.]

BTT