So where should we really start this post series? Well, at the most-logical spot: the actual part of the gun that is legally the "firearm".
Without going too far down the rabbit hole of legalities and idiotic restrictions, the Bureau of Alcohol, Tobacco, Firearms, and Explosives (hereafter referred to the BATFE when necessary) is really only concerned with one single part on your gun – the piece that carries the serial number for the entire firearm. If you were to strip everything else off that piece, that one piece would be the thing you would have to have a background check executed on you to purchase from a gun store. In the case of AR-15s, it is that "lower" you always hear about (the full term is "lower receiver", since ARs also have an upper receiver); on bolt-action rifles, it is the tube (but not necessarily the barrel) the bolt slides around in; for 1911s, the serialized part is the "frame"; on Ruger Mark I/II/III pistols though, the BATFE only cares about the part with the barrel on it (which has to be a pain in the ass).
In other words, the definition of a "receiver" is fairly arbitrary, but it generally boils down to, "the serialized part that holds all of the other parts of the firearm together, in the right orientation to function properly". Arguably, an AR-15 upper would work just fine without the lower so long as you had a hammer and fairly long punch handy, but the BATFE "had" to pick on part as the actual firearm, and here we are.
So how about the 10/22? What constitutes the serialized "receiver" on those things? Well, in AR-15 terms, it would actually turn out to be the upper receiver – the part that holds the bolt and that the barrel is inserted into:
That part, and that part alone, is the actual "gun"; everything else on the 10/22 can be shipped straight to your door, no questions asked, but to take possession of that part from a firearm dealer, you will have to show up to the store in person, present your identification, undergo the required background check, and pass it. It is a bit wierd when you think about it like that, is it not?
With all those legalities covered, you have approximately two-and-a-half options when it comes to the receiver in your assemble-it-yourself 10/22.
First, you could just buy an existing 10/22:
This route has a number of advantages:
1. You will always have a fully-functional, actual firearm; not just a single machined piece of metal that is not good for much by itself except holding papers down.
2. Anything you replace on the rifle will always have a spare part, in the form of the original.
3. Depending on what you plan on replacing, this could be significantly cheaper than assembling from the ground up.
4. You do not have to buy the little fiddly bits that all guns have, like the receiver pins or v-block screws.
But there are also a few hitches:
-1. Certain features are all-but unavailable on standard receivers; specifically, a cleaning hole on the back of the receiver and rails along its top. The former only matters if you use a cleaning rod and want to clean in the "right" direction, and the latter is fixable with screw-attached rails, buying the apparently unavailable Tactical 10/22, or going with an SR-22 (which is just a 10/22 in a special body), but if you want a unibody rail or that hole, you are probably going to have to go aftermarket.
-2. Depending on what you plan on replacing/attaching (specifically, if all you plan on keeping is the bolt and receiver itself), this could actually turn out to be more expensive.
-3. Ruger 10/22 receivers are universally die-cast aluminum, though I cannot seem to find what type. If you want a billet receiver, or a stainless steel one, you are going to have to look elsewhere.
-4. I have been hearing that Ruger’s quality has been sliding of late. If their stock bolts are any indication, I would tend to agree with that assessment, but mine is only one data point.
-5. Aftermarket receivers supposedly have better tolerances, meaning tighter fits of all of your various parts and, in the end, potentially better functioning and accuracy. Of course, "tighter fits" can also mean "binds up", and I am not entirely sure how you can have better dimensions than the people who set the standard, but that is what some non-Ruger companies claim.
Alternatively, you could buy a virgin 10/22-clone receiver:
You can go with ones that are virtually identical to the original, all the way up to custom-fabricated, specially engineered rigs, or even options that include such oddities as AR-15-style charging handles or the "dual-arm straight pull" actions our biathlon competitors use (which is functionally bolt-action, by the by, in order to circumvent stupid European laws).
Really, the only upper limit on those is your budget; depending on company, features, materials, and other options, you could easily spend more on a receiver than you could on a nicely-built direct-from-Ruger all-up rifle. But if that is what you want, and you have the budget, it is there.
One final thing to bear in mind with aftermarket receivers, however, is that they are aftermarket and are not from the original manufacturers. While Ruger does publish specifications as to what the dimensions should be for a receiver, it is entirely likely that aftermarket producers decide they know a better way to do things, or that their tolerances are too tight, or not as tight, especially since Ruger only really specifies the important dimensions (whatever those are in a 10/22’s case) and leaves the rest up for artistic license. More on this in a bit.
So what about that half-an-option? Well, in addition to purchasing an aftermarket receiver, you can also purchase something that you make into a receiver:
These are commonly referred to as 80% receivers, and the interesting thing with them is that they are not legally defined as "firearms". Due to not having certain holes punched out of them (specifically the receiver cross pin holes, the bolt stop pin hole, the barrel hole, and the v-block screw holes), the BATFE does not define these lumps of metal as "firearms", and, as such, they can be shipped to your door without a serial number, registration, or background check. They are, however, somewhat useless in their current form.
Which is why the same company will sell you the jig to line up all of those holes, and with the help of a drill press, you could have yourself your very own 10/22 receiver that exists on no books anywhere. The complete kit is a bit expensive, especially with the required drill bits, but it is guaranteed to give your average “gun control” extremist a raging case of hoplophobia. (Note: once finished, you cannot sell that receiver without first serializing it and registering it with the BATFE.)
So what did I do? The middle option – I got a finished receiver from Tactical Machining. Since I would only end up keeping the receiver, bolt, and various fiddly pins and screws from the original rifle, and since I would have to end up mounting some kind of rail system on the receiver regardless, this actually turned out to be marginally cheaper than buying an off-the-shelf rifle and modifying it appropriately, especially with a $10 off "LIKE10" coupon code (which may disappear shortly after me posting this – it is only a year old – so use it fast if you want it). Additionally, it bemused me to try to build a rifle designed by Ruger without using any actual Ruger parts (my budget did not quite allow me to accomplish this, as we will discuss later). Finally, I will freely admit that a not-screw-attached rail system on the receiver gives me a warm fuzzy; I know screws can be tightened and secured to the point where it does not matter, but the fewer removable interface points, happier the engineer side of my brain will be.
I am going to hold off reviewing the individual parts (if I ever get around to doing so) until after I get a chance to put this all together and actually shoot it, but here is a brief comment to tide you over for that future eventuality: My Tactical Machining receiver required a surprising amount of gunsmithing to work with the parts I purchased. The barrel I bought was an impressively tight fit requiring somewhere over an hour of sanding on the barrel shank to get it fitted into the receiver (almost completely consuming the emery cloth the barrel fabricator provided), but I expected that, and it is not such a big deal. However, the stock I purchased required fitting to be able to mount the TM receiver, and a bone-stock Ruger bolt hangs up on the rail that projects inward from the ejection port. I have contacted the company, they agree this should not have happened, but they have not provided potential solutions for the problem yet.
Now it is time to clear up a few misconceptions.
Yes, I bought this receiver online. I placed my order with Tactical Machining through their webpage, paid with my credit card, and handled the entire transaction electronically.
No, this receiver could NOT be mailed to my door. It was the only part I could not, personally, receive, but this receiver, useless by itself though it may be, constitutes a "firearm", and thus could not be sent to me directly.
Yes, I had to go to a Federal Firearm Licensee to pick up this receiver.
Yes, I had to undergo, and pass, a background check to pick up this receiver.
This is the same for functionally all online firearm transactions. Unless you are purchasing the firearm from a person who is not a dealer but who is in you state and is willing to meet you face-to-face (in states where face-to-face transactions are legal), all online firearm transactions must go through an FFL and involve a background check. I know, idiots, useful and otherwise, are going positively apoplectic over the notion that law-abiding citizens can purchase firearms from the intertubes, but much though I wish it were the case, it is not nearly as simple or uncontrolled as they make it out to be.
(Bare Ruger 10/22 receiver image borrowed from this GunAuction.com listing. Wood-and-blued Ruger 10/22 carbine image borrowed from Ruger. Virgin 10/22 clone receiver and 80% receiver images borrowed from Tactical Machining.)