rec'd by email. it cost you nothing to read...take it for what it's worth.

>>> SAFETY ALERT <<<<   PRODUCT WARNING

Re: Frame Rivets for stamped receiver Kalashnikov type rifles.

K-VAR Corp. is providing this information in response to a
significant number of inquiries concerning the general use of
rivets used to affix and secure the trunnion and rear blocks to the
frame on all stamped receiver AK type rifles.

The most important thing to know about this subject is THESE
RIVETS HOLD THE ENTIRE FRAME TOGETHER and are
crucial to the structural integrity of the frame.

That makes these very small parts very important. The quality of
material and correct dimension and configuration of these parts is
vital to the safe use of your firearm.

As you know, when in proper working order a firearm in action is
basically a controlled and contained rapid expansion of gas and
pressure that expels a projectile out of the muzzle.

If that control and containment is compromised, then a jam is the
least of your worries. Improperly contained this discharge quickly
turns into a disaster.

So, what does this have to do with rivets? What difference does
it make?  Once again, THESE RIVETS HOLD THE ENTIRE
FRAME TOGETHER.

Below are some of the questions asked and responses by our
technical staff. Please read these advices. It's important for your
safety.

Q.: Why all of this debate over a part as simple as a rivet?
A.: When the stamped receiver AK was first developed and
fielded, significant shortcomings of the design began to appear
(ie...the rivets sheared off and the frames feel apart after
repeated firing).

As a result, for some time, production of the stamped receiver
version of the AK was suspended. After lengthy R&D the source
of the shearing was isolated and a solution found. The flat
bottom of the rivet allowed movement of the frame components
during firing. These components (namely the frame) got looser
with each successive impact of the action parts in movement
until the rivets sheared off and the frame failed.

The solution was to redesign the rivet head to include a beveled
or chamfered head bottom that in turn locked into the frame and
trunnion blocks when attached. This created a solid bearing
surface which firmly lodged the rivet and prevented shearing.

Solution found, the stamped receiver went into full production
and AKs filled the world.  


Q.: What's the difference? A rivet is a rivet.
A.: Not actually. In a proper rivet set for the AK (depending on
country of origin) there are up to 6 (six) different styles of rivet
used.

The dimensions and individual style of the different types have a
specific location and configuration to perform a specific function
and are not interchangeable. Improper installation or using
incorrect rivet parts will result in catastrophic failure at the rivet
attachment points.

But, it gets worse.

If the rivet material is incorrect, the problem magnifies. If the metal
used in a improperly shaped rivet is too hard or soft on the
Rockwell scale, then the catastrophic failure happens all the
sooner. The wear or shearing that occurs is magnified and
accelerated if the Rockwell property doesn't match the specific
material specification required.

The combination of incorrectly shaped rivets that allow shifting
and additionally do not conform to the material specification is a
recipe for disaster.

See illustrations on K-VAR's Online Forum  here is the link:
http://www.k-varcorp.com/cgi-bin/forum/ikonboard.cgi?
s=3eee3586de4bffff&act=ST&f=2&t=50&st=#entry1


Q.: So, what are the different rivet configurations for the various
AKs?  
A.: The three most common configurations are:
Romanian (14 total)> 2 long chamfered, 1 long thin flathead, 5
short roundhead flat bottom, 4 short chamfered roundhead, 2
short flathead chamfered.

Bulgarian (15 total)> 1 flattop long chamfered, 2 short chamfered
roundhead, 1 long thin flathead, 4 short roundhead flat bottom, 1
short heavy cylinder head, 4 short chamfered roundhead, 2 short
flathead chamfered.

Bulgarian-side folder (17 total) > 1 flattop long chamfered, 4 short
chamfered roundhead, 1 long thin flathead, 4 short roundhead
flat bottom, 1 short heavy cylinder head, 4 short chamfered
roundhead, 2 short flathead chamfered.

       
Q.: I've seen less expensive rivet sets from other vendors.
A.: Yeah, we've seen them too, even purchased some to
compare to our products. Frankly, the one's we've examined just
won't work.

Let me clarify that statement.

They will work, but, the result will be eventual catastrophic failure
due to the causes we've outlined above.

Simply put, I wouldn't use them on my gun.

What you need to decide when purchasing a rivet set in regards
to price is A. Will the lower priced product you intend to buy be
inferior or dangerous & B. Is your life worth $5.00?



We hope this clarifies some of your questions. Your safety is
important to us.

http://www.k-varcorp.com/rivet2.html
http://www.k-varcorp.com/rivet3.html

K-VAR Tech Department
www.k-varcorp.com

i think the issue of rivets and the countersink is a little overblown, much like the receiver hardening...but, ya might as well do it right the first time.

of more importance than whether or not you use a commie rivet is getting a tightly set joint.

the rivet is soft. it will "flow" under hammer blows to fill voids if properly bucked.