View Full Version : Receivers: FAC/Dan Coonan (DCI) receiver Hardness test

December 06, 2002, 23:17

I contacted Dan Coonan for information about his receiver that FAC sells. This is the response he sent me. This might answer some of the questions that more than a few of the members here have about them.

There is information concerning the hardness of FAL Receivers manufactured by Imbel, DSA, Enterprise, etc. in a post dated Oct. 31st in the Review Form that I believe was started by Meepers when he reviewed a U.S. Armament Receiver.

I hope this helps.



We have done a fair amount of hardness testing of various FAL type receivers. The only receivers that should be used as a benchmark or standard are the Imbel commercial and contract (military) receivers and the various receiver remnants
found on rifle kits. The most common of these receiver remnants is the front end section; still attached to the barrel. We have just recently
seen center sections and back end sections from L1A1 and G1 rifles. Here is the scoop in a nutshell: All Imbels and contract (military)
receivers are SOFT!!!!!! LESS THAN 20 (TWENTY!) Rockwell 'C' Scale, with the EXCEPTION of the UNDERLUG/LOCKING LUG AREA. The Underlug/Locking Lug area has been spot treated by either induction or resistance heating to the critical or transformation temperature and quenched ; no tempering. The result is a hard spot, about 57 Rc, blending to 18 -20 Rc within 1/2 inch radius. Our best engineering analyses of this spot treatment (and we sent our head engineer on an all
Ireland Pub Crawl BEFORE he kissed the Blarney Stone!) is this: They wanted the locking lug something better than dead soft - around 25-30
Rc. So they spot hardened and quenched. By eliminating a Draw or Tempering operation, they saved BIG BUCKS! - and that's the only reason
it's 57 Rc and not 25 Rc.
Our parts are Normalized, Hardened, Drawn - three different heat-treat operations - to 25 to 30 Rc and then fully machined in this hardened condition. We have tried other methods. This is the most predictable. DSA receivers measure 25 -30 Rc anywhere and everywhere. Some people
claim their receivers are 'rock hard' - they fail to claim they have rocks in their head!
As an added note, this is an extremely hard part to check accurately. We have been forced to SECTION parts and prepare them for hardness
evaluation. The inclination is that the parts measure softer than they are due to part movement while testing, and the heat-treater making them
harder because of the lower readings, This can be SO MUCH FUN!!!!
I have more to say, but I think I'll have a pint of Guinness before the Blarney wears off!
Thanks for giving me this opportunity!
Dan Coonan

December 07, 2002, 00:13
Thanks for the info on these receivers. Let them ban Imbels I think we may have what we need a good priced US receiver.:fal: :fal: :biggrin:

December 07, 2002, 00:33
That explains the darker spot just behind the locking shoulder on my Imbels. I think. I think a Coonan is my next receiver. Maybe my Imbel barrel will fit better on it. :D

December 07, 2002, 00:46
Originally posted by McDobber

I contacted Dan Coonan for information about his receiver that FAC sells. ...

Our parts are Normalized, Hardened, Drawn - three different heat-treat operations - to 25 to 30 Rc and then fully machined in this hardened condition. ...

Good! Dan Coonan sounds like a great guy, and it's nice to have some remarks of his on the board. And complete heat treatment is the best way to go, I think.

December 07, 2002, 03:36
Essentially, a receiver fabricated from 4130 prehard,... good stuff,... and Dan Coonan sounds like a class act,.. imagine that!,... someone in the gun industry who actually has a sense of humor!

I'm impressed with the fact that he approached the tempering process as he did, and I'm also impressed that he ended up with a receiver which is pre hardened to 25-30 Rockwell *then* machined. That's the way that it should be done. Doing it in this way eliminates the distortion which would obviously occur if they were heat treated after machining.

My next build is going to be a Coonan.

Lazy Horse
December 07, 2002, 06:15
I have one in the safe and another being built by Tony of M&M guns. Tony says that Coonan Receivers are GREAT. I have now ordered another from Harlan at FAC I am so impressed with them. AND its US made. Russ ( Lazy Horse )

December 07, 2002, 10:07
If I remember from my days in metals the heat treat first then machine makes the metal every bit as strong as the best of the forgings it is the best way to go even tho it would not have to be done this way to make a good receiver. Dan deserves every bit of the money he makes on these receivers. For once there is a guy that wants to do the job right. DSA will always be great but costly. But look at Enterprise for a couple of years there receivers had very bad heat treating that was not there fault they were ripped off by a contractor. I had one built on one of there receivers from that time and it held up fine after the 2500 rounds I put threw I wish I would have kept it tho. My point is Dan did not have to heat treat and then machine to make a good receiver he took the extra step to make a great receiver something you don't see in the Military semi auto rifle world.:fal:

December 07, 2002, 11:57
The fact that Mr. Coonan runs a normalization cycle on the recievers before the hardening cycle tells me much about his understanding of the heat treat process. Its really a simple matter, but most folks either dont care, dont know, or dont take the time (talking about heat treating in general, not just recievers). Im gonna have to try one out.

December 07, 2002, 12:32
Great response from Connan! Good to see a manufacturer that will take the time to answer questions about his product. This has helped to make me feel better about ordering a pair of these for my next two builds. Hope they will be in by the end of the week.

December 07, 2002, 13:00
Hey Dwight and Bryan...pay attention here. This is how you treat and keep customers (pun intended).

December 07, 2002, 19:56
I had to drive down to Atlanta today to take a G1 build to Tony at M&M Gunsmithing (UPS wouldn't ship it for me) and I took a look at an Israeli HB that he built on a Coonan receiver. He spoke highly of them, and the HB was a great looking rifle. I think my next receiver might just be a Coonan.

December 23, 2002, 14:29
Sounds like a product that can compete head to head with DSA's receivers?????

Better bang for the buck.


December 23, 2002, 15:10
i ordered 1 when they went on sale for $199 hope they are like everybody says. and from dan's reply you can tell that they did their homework before they started production. lets just hope that they one day make a true inch receiver. speaking of which how about somebody posting the e-mail address and everybody e-mail dan coonan expressing interest in a inch receiver

December 23, 2002, 16:19
Ever see one of dans .357 mag 1911 clones? I was too young and had no money for one back then. Ahh hindsite aint it a b>>ch.

December 23, 2002, 18:18
Originally posted by HD99FXR3
... speaking of which how about somebody posting the e-mail address and everybody e-mail dan coonan expressing interest in a inch receiver

I would rather have Dan Coonan doing something more productive than reading emails that all say the same thing. I'm sure he knows there's interest in an inch receiver.

Instead of emails, let's use a thread in FAC's forum. Here's one already started....


December 23, 2002, 22:19
I emailed Dan in October regarding that very thing. His biggest obstacle it that...He's really buisy...REALLY BUISY!
Hopefully, he'll have something soon. I know I'm ready for it.
Just imagine, an "Inch" receiver that doesn't say Entreprise on it...ohhh bliss! (Gett'n a woodie just thinking about it) lol

December 26, 2002, 10:48
The New Year is sure to bring New things!!!

Looney Tunes
December 27, 2002, 02:30
that's it. i am ordering two from FAC early in january. i am very impressed with dan's willingness to build a quality receiver for a reasonable price. thanks dan & FAC. 8^)