Im finally going to take the plunge and get my sot in july. In preparation, I've been doing some research on what would be "easiest" to manufacture. I do have m16 cut lowers that would require nothing more than a pin and trigger parts, but if I ever relinquish my sot I'd have to cut them up. On the other hand, if I can manufacture a dias, I could just destroy it. However, I'm not sure if I could make a dias. What do you you guys recommend?

I feel like lowers are cheap enough that the risk of making an oops is less a concern than fussing with a dias, but as a peasant, I've never made either.

Not a SOT or a MG owner (maybe someday), but If I were investing the time, energy, and money I'd want the real deal 3 position switch. Ultimately a single lower receiver isn't a tremendous investment.

Make sure your SOT location is zoned for manufacturing.

Plenty of New SOTs learned this the hard way

M16 fire control pocket lower, Bowers autosear jig, engrave, done.

By "easiest to manufacture", I guess it kinda depends on what you're starting out with.

If all you've got is a hunk of raw aluminum, there's far more features and critical dimensions to nail to make a complete lower receiver, even without the 3rd pin hole.  A DIAS is a couple rectangles with some notches and holes in them.  You could bang out a batch of DIAS from a manual mill.

Now, If you're starting with an 80% or 100% semiauto lower and have some jigs, then doing the lower could be easier to do.  DIAS = machining something like 20 flat surfaces.  Converting a low shelf receiver to a MG = drilling 1 hole.

DIAS - cheaper to manufacture.  I dont know the cost of raw stock these days.  I would not be surprised if the cost of complete lowers vs DIAS was 10:1.  You maybe got $2-5 worth of steel to make each one.
3rd pin lower from scratch - you're gonna need a CNC .  
3rd pin lower from mostly complete lowers using a jig - Your cost per item is higher.  You can't really batch these out to save time or cost.  Whatever it takes you to make 1 of them, multiply your time and cost by 100 and thats what it takes to make 100 of them.

Maybe you are confusing a DIAS with a LL.....you still have 3 position with a DIAS.

I have both DIAS and full auto lowers.

A DIAS can be lost and typically takes a few more seconds to deal with than a true sear when swapping uppers.

Pictured below is my favorite MGI modular lower setup.  I have one that is a post sample but also several that are not drilled for when I no longer have the SOT.   So all the tinkering Ive done and all this setups I can still run with my transferrable DIAS.

Also think about all the specialty lowers like ones that take special mags.   I wouldn't drill them as they are worth more as title one.  With an SOT, just make more DIAS if you want.

If you give up your SOT all your mgs become no law letter guns you can sell to another SOT. An m16  lower will sell for 300 to 500 dollars.

Just drill a hole in lower and be done.

I'm not understanding. I have a 07 ffl, but I cant get the sot without manufacturing zoning? Where can I find more info on this?

Your local laws.

Say you want to be an FFL and do transfers for people.  If you are not zoned for a business where walk in foot traffic is allowed, then nope, you cant do transfers.  
And in your case, if you want to manufacture things, you have to be in line with your local zoning ordinances.  The ATF giving you a slip of paper does not let you violate state and local rules.  You have to follow them all.

They're both pretty easy. If I got my SOT, I would make both along with a glock switch and Maxim DIAS. Probably build a few auto connectors as well.

County auditor should show how your property is zoned. If you live in a urban or a urban area chances are you won’t be able to run a business and certainly not manufacturing out of your home. If you live in the country it’s pretty much do what you want.

This is one of many hurtles people face when opening up a FFL/SOT. Everyone assumes it’s a loophole to get cheap MGs, but it’s really not. If it was that cheap and easy transferable MGs would not be selling for tens of thousands of dollars.

Another option is to go the FFL/SOT dealer route and buy pre-may samples which are a bit cheaper than regular transferables, then give up the license and you get to keep the pre-may samples.

As well as the state laws and and local ordinances that the zoning board enforces, your home/shop owners insurance company may also have a say in what you decide you can afford to pursue.

MHO, YMMV, etc.  Best of luck.  Be well.

reading thu posts wondering if anyone thinks like me....found him

You can easily get an FFL/SOT home business going cheap, if other allowed home businesses exist.

I was told by the field agent I could get a sot. She checked my zoning when I first applied for the 07 ffl. I was thinking you meant I HAD to get manufacturing zoning.

Sounds like you're covered.

Attached File

If you have an M16 pocket lower, that is the easiest. Add your info, drill hole, done.

When giving up, FFL/SOT, strip all parts out or sell a post sample.


eta

looking at responses, it is easy to who the FFL/SOT been there, done that and who are not.

If easiest is the criteria, then you could 3d print a swift link, however don't expect it to last all that long.

If your criteria is to have a gun that functions well with the least amount of machining then you go with a M-16 pocket lower (to avoid having to mill the inside) then use a jig to drill the 3rd hole. At that point just engrave your info, fill out the form 2 and put in full auto parts.  Even if you didn't get a lower with an empty pocket, it isn't that hard to mill it out and the dimensions are not all that critical as long as the parts fit in.

With the DIAS, you may have an issue getting the timing right and need to harden the trip or it will get chewed up.

You could also make a lighting link but would need a SP1 bolt carrier.

Might as well just get a lower and do it right. They are not all that expensive and in the end, you can sell it to another manufacturer without a law letter.

Even LL can have 3-position select fire.

I have two lowers set up with Colt M16 FCGs for lightning links and both have Safe/Semi/Full function. Of course with the LL pulled out they’re just Safe/Semi/Semi.

IMO if you already can/do finish your own 80% lowers, cutting the FCG pocket to M16 spec and punching a third hole is almost zero extra effort.  DIAS are pretty simple to build.  Two drills, a 1/4” endmill, and a 1/8” corner radius cutter are all cheap and can chew through a bar of prehard 17-4PH pretty easily even if all you had is a cheap Harbor Freight bench top mill.  But it is still something you’d have to machine... not difficult, but extra work nonetheless if you can already finish your own 80% lowers.

DIAS advantage is really only realized when compared to pricy transferable RR; destroying an RR in an accident is gut wrenching and available transferable RR are all dated.  An RDIAS is nearly indestructible and you can drop them into most modern lower receivers to make contemporary builds.  Both those attributes are only valuable to people who can’t legally build their own new 3rd hold lowers - they’re stuck with shooting old RR’s or old indestructible RDIAS in new receivers.  If you can cut your own M16 lowers, it’s simpler and easier.

Yes, I am well aware of that by using the A2 burst kit parts.  I was generally speaking as most people don't know about the burst kit either.
On that note, I do have a buddy that broke his RLL and his was setup using the burst kit.  He was in a SMG match at the time running straight blowback 9mm.  This was over 10yrs ago.  No delayed blowback 9mm M16 configurations existed back then.  The burst kit was given to him by another friend of mine that also had a RLL.  The guy that gave the burst kit away didn't like it as he thought that using the dual disconnector springs put too much stress on the link.  BTW both guys were using the KNS RLL protectors as well.  My friend with the broken link sent it to M60Joe back then who welded it back together and he sold the RLL.

I personally never liked RLL's as I don't want to deal with SP1 spec carriers.

As an FFL / SOT, I would definitely do 3rd hold lowers as well DIAS.  

3rd hole for whatever typical M16 setups and DIAS for hosts you want to keep after dropping SOT or are unsure if you want to keep.

A few more examples I forgot to mention are like the Colt 901, DPMS G2 and Sig MPX.  The first two are not made anymore and then there is the Sig MPX which also works with a DIAS with very little work.  
Since the first two aren't made anymore, you may not want to drill the 3rd hole and FA 308 may not be all that desireable either.  That is the case for me.  Kind of a novelty and I wanted to see how smooth I could get it and also curious on tuning the cyclic rate.  475 RPM unsuppressed and 508 RPM suppressed with adjustable gas block for those that are curious.
When I drop the FFL/SOT, I'll keep the 308 but no real interest in running them in FA anymore.

On the Sig MPX, I ended up hating the platform and so glad I didn't drill it.  Gassy, loud and cyclic rate is too fast.  (I like all my MG's to run in the 600's to 700's unless we are talking 22LR where I just care about reliability).
MPX cyclic rate below.  I removed the post same DIAS and had a bidding war on Gunbroker to get rid of it.  Sure, I could have drilled it but I don't think I would have gotten the money I got on Gunbroker and you have a much larger buyers market if not drilling the hole for this gun.

Not to get too far off topic... but where did it break?  KNS protector?  Because I can’t imagine one breaking the ears off with a KNS protector.  Regardless, I’ve always wanted to put reduced-power disco springs in my dual disco hosts, but never got around to it.

Plus, if I pretty much never put the sector in semi auto - the link basically only ever is tripping one disconnector.

Yes, one of the ears broke off.  Don't ask me how.  I just saw the aftermath.