[TML] 20mm

[Tod Glenn]

On Jan 21, 2008, at 1:27 PM, GDWGAMES at aol.com wrote:

>>> How big does an alien need to be to use a 20mm as a standard long  
>>> arm?
>>
> IMO, not much larger than a human. 20mm antitank rifles were  
> standard issue
> in some WWII armies, but they had to be fired prone (ususally off a  
> bipod or
> monopod) because of the recoil. Solothurn is the one that comes to  
> mind
> immediately, but I'm sure the gun nuts on the list can provide full  
> details on all of
> them.
>

There were a number of 20mm anti-tank rifles fielded in WWII, although  
they quickly became obsolete due to improvements in tank armor.  The  
Lahti L-39 was probably the most common.  Others include the already  
mentioned Swiss Solothurn S-18/100, S-18/1000 and S-18/1100 as well as  
the Japanese type 97.

20mm have made something of a comeback as anti-material rifles, with a  
few being fielded.  The South African NTW-20 is the best known western  
design, but there's an interesting Croatian 20mm rifle that uses  
reactive counter recoil (similar to recoilless rifles) The RT-20.   
Even with recoil reduction, full power 20mm are the upper limit of  
what a human can tolerate in terms of recoil.

Even larger calibers like the Barrett 25mm 'Payload rifle' exist, but  
these use reduced charge rounds to keep recoil manageable