rivet questions
Here is the end all for rivet questions. I
have access to look up the National Stock Numbers (NSN or old FSN). Here is what
the government used for rivets. I will refer to the part number from figure B-14
of TM 9-1005-212-25 which can be found on the main page.
Part #27
NSN 5320-00-502-4602
Item Name: Rivet, Solid
Fastener Length: 0.505 Inches Nominal
Head Style: C9 Flush Countersunk
Shank Diameter: 0.186" minimum and 0.188" max.
Shank Style: D9 Straight
Head Major Diameter: 0.250" Nominal
Countersink Angle 60.0 Degrees Nominal
Material: Steel Comp 1035 Overall
Part # 28
NSN: 5320-00-502-0600
Item Name: Rivet Solid
Fastener Length: 2.025" Nominal
Head Style: C9 Flush Countersunk
Shank Diameter: 0.340" Min & 0.343" Max.
Shank Style: D11 Straight with tapered tip
Head major diameter: 0.401" min & 0.406" Max.
Chamfer Length 0.016" nominal
Tip Diameter 0.312" nominal
Countersink Angle: 60 degrees nominal
Material: Steel Comp 1035 overall
Part # 33
NSN: 5320-00-515-2737
Item Name: rivet Solid
Fastener Length: 0.437" nominal
Head Style: C9 Flush Countersunk
Shank Diameter: 0.187" nominal
Shank Style: D9 Straight
Head Major Diameter: 0.272" nominal
Countersink Angle: 60 Degrees Nominal
Material: Steel Comp 1035 Overall
Part # 34
NSN: 5320-00-502-0711
Item Name: Rivet, Solid
Fastener length: 0.500" min & 0.510" max
Head style: C14 Fillister
Head Height: 0.094" nominal
Shank Diameter: 0.197" min & 0.200" Max
Shank Style: D9 Straight
Head Major Diameter 0.295" min & 0.300" Max
Special Features: One side of head flattened to OD of shank
Material: Steel Comp 1035 overall
Part # 35
NSN: 5320-00-502-0522
Item Name: Rivet, Solid
Fastener Length: 2.043" nominal
Head Style: C12 Oval Countersunk
Shank Diameter: 0.197" Min & 0.200" Max
Shank Style: D9 Straight
Head Major Diameter: 0.269" nominal
Countersink Angle: 60.0 Degrees nominal
Material: Steel Comp 1035 overall
Part # 36
NSN: 5320-00-502-0601
Item Name: Rivet, Solid
Fastener length: 2.557" nominal
Head Style: C9 flush Countersunk
Shank Diameter: 0.183" min & 0.186" max
Shank style: D11 straight with tapered tip
Head major diameter: 0.256" min & 0.258" max
Chamfer length: 0.016" nominal
Tip Diameter: 0.155" nominal
Countersink angle: 60.0 degrees nominal
Material: Steel Comp 1035 overall
I hope this answers some questions as to rivet length and diameter. If there is
another part that you need info about, e-mail me at:
usafredhat@aol.com
Or, take a tip from the legendary RKM and use a length of mild 3/16", which is just long enough to fit through the trunnion and have both ends sitting below the level of the countersink. Fire up the MIG welder, drop a bead on each end and file flat or form a round "rivet" head. Indistinguishable from a real rivet and very fast. Incidentally, it fulfills the requirement of welding the receiver together.
The only requirement for a serial number is that it be
unique (i.e. you as the MFG haven't used it before; it could be the same
serial as another MFG's gun) and that it be over .002" in depth. This is a new
requirement since 1/02. No longer can you photo or laser etch a serial number.
Some people use their initials and a number, i.e. SPG001. That's the system
that the NFA branch recommends.
Other MFG use a date code, like Special Weapons- "SW5-99-12-####". The SW5 is
the Model, the 99 is the year, the 12 is the month, and the #### is the actual
serial number.
I like to use serial numbers that identify the model and then the serial
number, or if it's a contract gun, I use the person's initials and then a
serial number.
So, my cans are P9#### for 9mm cans, P50#### for .50 cal cans, and P50K####
for the short .50 cans.
SImon
The most important thing is the pre-heat. Get your kitchen oven as hot as possible, and let the receiver sit in it for 30 minutes or so. That will get it up to around 550 degrees. Take it out, make a weld, and put it back in. Repeat every 10 minutes or so until the whole receiver is welded.
I weld the bottom plate for about 1.5 inches at the forward end on both sides; I weld the top plate for about an inch both sides, and the underside of the trunnion to the sideplate both sides. That way, there are only 2 of 3 welds visible.
Another option is to remove metal from the bottom plate. You can grind or mill down the top of the skirt (that the rivets go into) at the forward edge. When you weld to the sideplate, you essentially build back up this contour and you can then mill/grind so that the weld is invisible.
Before the gun is riveted, I bevel the edges to be welded so I can run a decent bead and not have to do any post-grinding, but you can grind the bevel while assembled.
Personally, I keep the welds visible so that there's no question it HAS been welded, but if I were gonna be a perfectionist, I'd do the latter. I do partially grind down the skirt just so I can put a large bead down and get good penetration, but I don't make it too cosmetic.
MIG welding is easy. I would have no hesitation welding the receiver; any fuggups can be fixed with a grinder. Just pre/ and post/heat the receiver to avoid cracking, grind a good bevel and be meticulous about cleaning the area to be welded. Make sure it has been completely degreased (use acetone), and grind down to bare metal so the bead will stick.
This site contains information on legal 1919 semi- and full-auto firearms. The information in these web pages is not intended to be used to construct illegal devices, nor is it intended to be viewed by minors. All NFA rules apply.
