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draconianruler
06-22-2008, 10:40 PM
Anyone have more info on the .50 Fat Mac round? It is suppose to be a necked down 20mm cartridge :eek: Now that would be a round to have :cool:

ke6guj
06-22-2008, 11:11 PM
All I know is that Gale McMillan designed it a while back. It did not work out since it was a barrel burner. Barrel life was less than 100 rounds, IIRC.

draconianruler
06-22-2008, 11:21 PM
All I know is that Gale McMillan designed it a while back. It did not work out since it was a barrel burner. Barrel life was less than 100 rounds, IIRC.

Well that sucks :( Imagine the recoil on that monster.

Knight
06-22-2008, 11:23 PM
Found some info on it here (http://www.6mmbr.com/compcartridges.html), but it's not much:

A discussion of 50-caliber benchrest cartridges would not be complete without mention of the largest of them all, the 50 FAT MAC. Developed by rifle maker Gale McMillan, the Fat Mac is made from a drastically altered 20mm Vulcan cannon case. The shoulder is pushed back to a 30 angle and the case trimmed to a length of 2.6" with a very short neck. The primer pocket is modified for installation of a stainless steel flash tube and a standard BMG primer. Whereas the 50 BMG Improved can launch a match bullet to 3000 feet per second, the Fat Mac will propel the same bullet in excess of 3400 fps.

I've gleaned from other sources that the cartridge was abandoned due to the extremely short barrel life. No current rifles are chambered for it, no ammunition manufacturer makes it, and you'd probably have to make the cases yourself if you wanted to shoot it.

Skammy
06-23-2008, 2:56 PM
http://img.photobucket.com/albums/v626/Skammy/118538-big.jpg

I was thinking this :

http://img.photobucket.com/albums/v626/Skammy/imfifty.jpg

50 Shooter
06-23-2008, 3:05 PM
There's also the 14.5mm JDJ http://www.sskindustries.com/14_5.htm

I think this would have more potential here in Cali along with the .50 DTC.

ke6guj
06-23-2008, 3:15 PM
If I had the money and the need for another big boomer, that would be a nice way to go.

That 14.5mm JDJ is federally exempt from the DD rules, and CA's DD rules don't start until .60.

brando
06-23-2008, 4:57 PM
There's also the 14.5mm JDJ http://www.sskindustries.com/14_5.htm

I think this would have more potential here in Cali along with the .50 DTC.

Actually I'm pretty sure the 14.5mm (assuming it's the Soviet round) is classified a Destructive Device. It's too bad because for precision long range shooting, it is a superior round to the .50BMG. It has more mass and velocity approaching 3250 fps.

ke6guj
06-23-2008, 5:04 PM
As I already mentioned, the 14.5mm JDJ is DD-exempt federally. And CA's DD laws don't kick in until .60".

SSK has non Destructive Device exemption for a 14.5 MM (.585") cartridge.

SSK's 14.5mm JDJ rifle is based on a 50BMG bolt action. The cartridge has a Destructive Device exemption.

edit: Just to clarify, the 14.5mm JDJ is not the 14.5x114 Russian.

http://en.wikipedia.org/wiki/14.5_mm_JDJ
http://en.wikipedia.org/wiki/14.5x114mm

CSACANNONEER
06-23-2008, 5:24 PM
I believe that there is/was only one set of dies and one rifle ever made in 50 Fat Mac. There are a lot of fake copies of the round floating around but, they are not always to spec. It was an interesting experiment but, as stated before way to overbored and therefore a barrel burner.

JPglee1
06-23-2008, 5:28 PM
I'd much rather roll my own .50 using BMG brass with the neck lopped off .100" and the rim rebated a similar .100"... Problem solved for legality and easy to acquire brass....

Not the type of rifle you run 1000s of rounds thru in a weekend anyway.

How about a necked-UP .50 BMG using 14.5mm projectiles...would be 100% legal and definitely different.

J

ke6guj
06-23-2008, 5:31 PM
I'd much rather roll my own .50 using BMG brass with the neck lopped off .100" and the rim rebated a similar .100"... Problem solved for legality and easy to acquire brass....

Not the type of rifle you run 1000s of rounds thru in a weekend anyway. why make a new wildcat when there is already a mainstream .50BMG alternative, the .50DTC?

How about a necked-UP .50 BMG using 14.5mm projectiles...would be 100% legal and definitely different.

JThats what the 14.5mm JDJ is. And its only legal since SSK took the effort to get it DD-exempted.

JPglee1
06-23-2008, 6:17 PM
why make a new wildcat when there is already a mainstream .50BMG alternative, the .50DTC?


Cuz to me it would be easy with access to a lathe... remove a little rim and a little neck and problem solved. Short chamber the barrel and ream accordingly.

No need to run a different neck taper, so "surplus" or "pickup" brass could easily be used...

I dunno, just an idea ive kicked around for a couple years.

I have the skills to do it, for the average joe who just wants to buy n shoot, I'd go for the .510DTC as well.


J

virulosity
06-23-2008, 9:07 PM
I was thinking it would be cool to buy surplus 20mm rounds and neck them down to use .50BMG bullets. You would get lots of velocity with an already large bullet. Components should be relatively inexpensive since most 20mm aircraft guns are slowly being phased out...

JPglee1
06-23-2008, 9:08 PM
I was thinking it would be cool to buy surplus 20mm rounds and neck them down to use .50BMG bullets. You would get lots of velocity with an already large bullet. Components should be relatively inexpensive since most 20mm aircraft guns are slowly being phased out...

A lot of the 20mm is electrically primed...so you'd have to convert to percussion...then you have the huge powder volume to small bore size, which makes a barrel burner. Its 100% do-able but prolly not for the faint-of-wallet.

J

50 Shooter
06-23-2008, 9:44 PM
The other problem with that is finding someone to make you a receiver & barrel to handle it. Not to mention the stock and all the other work of putting it together.

Custom dies would also set you back about 1K+ and that's on top of finding a press big enough to load it. Like JP said, barrel burner indeed and that's an understatement. You have to remember that Gale had his own shop and could do whatever he wanted.

CSACANNONEER
06-24-2008, 5:28 AM
You have to remember that Gale had his own shop and could do whatever he wanted.

And, Gale gave up on the project!