Author Topic: Large Caliber Rifles (Read 389 times)

Neubob · « **on:** May 15, 2007, 10:52:59 PM »

I was doing some research on large-caliber rifle ammunition when I came across the .50 "fat mac". I was wondering if anyone here has ever heard of it. It looks like a 20mm case shortened and necked down to a .50. The result is a 3400 fps, 750 grain projectile delivering close to 20,000 ft/lbs at the muzzle. I've yet to find a rifle to chamber this round.

Here's the illustration:

storch · « **Reply #1 on:** May 16, 2007, 07:05:49 AM »

welcome back neubob

lasersailor184 · « **Reply #2 on:** May 16, 2007, 09:41:29 AM »

It looks like someone tried to do that super short case thing for which the name that I cannot remember right now. They tried to do it to some of the smaller calibers, and it wasn't incredibly popular.

Toad · « **Reply #3 on:** May 16, 2007, 09:57:39 AM »

Lazzeroni is the guy that is credited with bringing out the short, fat magnums. Winchester took that ball and ran with it. Lazzeroni, though, was undoubtedly influenced by the 6mm PPC developed by Louis Palmisano and Ferris Pindell.

The short fats are so incredibly unpopular that every major rifle builder is chambering them.

There's the .270, 7mm, .300 and .325 WSMs and then there's .223, .243 and .25 WSSms.

lasersailor184 · « **Reply #4 on:** May 16, 2007, 10:00:41 AM »

Well, they seem unpopular to me. I remembered several years back all these rounds coming out, and all the new guns being rechambered for them.

Then I've heard NOTHING for years.

Toad · « **Reply #5 on:** May 16, 2007, 10:03:44 AM »

Maybe you should get out more often.

Toad · « **Reply #6 on:** May 16, 2007, 10:06:26 AM »

BTW, I personally see no real need to nearly double the price of your ammo for the minimal accuracy gain and small increase in velocity.

But hey, the gun buying public is always chasing then newest way to down their game.

Which always turns out to be the old way: use enough gun and put the bullet where it needs to go.

Neubob · « **Reply #7 on:** May 16, 2007, 11:38:44 AM »

Quote

Originally posted by storch
welcome back neubob

Thanks. Nothing like a nice relapse, eh?

storch · « **Reply #8 on:** May 16, 2007, 01:58:14 PM »

the welcome back was not intended as a dig at you.

bustr · « **Reply #9 on:** May 16, 2007, 02:08:59 PM »

Here is a link to the specs....

http://ammoguide.com/?catid=445

FrodeMk3 · « **Reply #10 on:** May 16, 2007, 02:27:42 PM »

Man, if That's a .50 cal, and that case looks to be about twice as big as the projectile, making the case at least an inch in diameter....That would make the chamber end of any barrel it's chambered for about 2 inches in diameter in it's outside circumference. That thing would look like a funnel.

Neubob · « **Reply #11 on:** May 16, 2007, 02:37:03 PM »

Quote

Originally posted by storch
the welcome back was not intended as a dig at you.

I didn't think it was, Storch. If there was any cynicism in my response, it was strictly meant to be self-depricating.

Maverick · « **Reply #12 on:** May 16, 2007, 06:10:18 PM »

The neck looks too short to adequately maintain projectile alignment, compression and secure the projectile from coming out of the case inadvertently

FrodeMk3 · « **Reply #13 on:** May 16, 2007, 06:18:06 PM »

I'd like to see an unseated projectile for it too, Mav.

The one in the photo looks like it's already grabbing 1/4 in. of rifling before it's even fired. That would have to be one long bullet.

Maverick · « **Reply #14 on:** May 16, 2007, 07:01:53 PM »

It depends on how much the throat is relieved in the barrel / chamber combination as to whether the bullet would touch prior to firing. Running the shell to contact with the lands on loading would really require consistent cartridge length and case length in all shells. That's OK for a competition rifle but bad news for a "working" rifle.