Sunday, February 10, 2013

Necked down 20mm to a 50 cal..

Why hasn't anyone necked down a 20mm to a 50 cal and developed the ultimate long range crew served sniper system?


  1. Wouldn't the powder have to burn a bit quick? I vaguely remember reading of a wildcat cartridge dreamt up by somebody in Texas that had a 4.5mm bullet and a .50cal case. The bullet reached crazy velocities upwards of 4,500fps. Used against coyotes it basically liquidized the poor animal at extreme ranges about 1000m too. The rifle's lock time was worked on. But the time it took the powder to burn made making shots tricky.

  2. oh this wouldn't be something i could do at my reloading table. i'm talking about the boys at ATK or LaRue or some other big name taking a swing at it. i imagine it would be tough to do and the weapon itself would be a beast but that's where we're headed anyway. maybe a vehicle mounted sniper rifle ...

  3. Either that or laser queued indirect fire weapon.

  4. Gale MacMillan tried it years ago with the .50 Fat Mac but supposedly barrel wear was a huge issue.

    A more practical effort is probably the .416 Barret, which was specifically designed for shots at over 2000m range and pushes a specially designed 400 grain bullet to about 3250 fps. It has the same base dimension as the .50 round, so .50 rifles can be converted.

    Trivia: US 20x102mm is actually a necked out .60 machine gun round.


  6. There's a lot of factors to consider here that haven't been previously listed (ignoring the forum post I can't get too). In this case the biggest one is recoil. You'd have to be a helluva man to handle a round like that. Which is probably why you describe it as "crewed served." But I ask you, what kind of sniper needs/uses a crew? That's very un-sniper like.

    What would you use it for that current rifles/calibers don't already work? The US Army is currently using the 300 Win Mag. That's a hefty round in it's own right that's well suited to 1000+ yard shots in the right hands. Not to mention they already have the 50 cal for personnel at extreme distances and/or disabling vehicles. Your round sounds awesome, but I think it might be unnecessary. I know at least the SEALs also use the 338 Lapua Mag which another 1000+ yard round.

    You're also going to be looking at some serious ware and tear on the rifle itself. How many rounds do you think a gun like that could get off before its needs the barrel and a butt load of springs replaced? How many rounds can it get off in a short period of time before overheating?

    Another thing to consider is simple ballistics. A bullet, like everything, has a terminal velocity. After it gets going so fast one of two things will happen: it will literally come apart or the turbulence will cause it to become unstable and veer wildly off course in an unpredictable direction.

    1. the Marine Corps is looking at Sniper Teams of about 6 to 8 guys now. break down a weapon and have each guy carry a portion...setup on a hill top, establish security and have a weapon that can accurately reach out to 2...2.5 miles might have applications. i'm thinking more ma deuce type weapon than some shoulder fired rifle. oh and the round that is a winner that BB1984 named is the 416. i saw the ballistics tables on that bad boy and i'm wondering why no one is using it for sniper work. i'll find it and post it here.

  7. How about:



Note: Only a member of this blog may post a comment.