Depends on the application. If you mean power, the higher the caliber, the more powerful it is. for example, a .22 caliber rifle is much less powerful than a .50 caliber rifle.
We can't really answer that until we know WHICH 45 and which 50. In the case of a muzzleloading black powder rifle, the .50 with have more energy, all other things being equal. However, it could also compare a 50 muzzleloader to a .45-70 cartridge rifle, which is more powerful. Caliber alone only tells us the width of the bullet.
Rifle or handgun?
Any caliber can do the job. Most states regulate what can be used.
A VERY large caliber, VERY powerful rifle. It is the .577 T-Rex.
Both Shinsung and Sam Yang make a 50 caliber air rifle. The largest caliber Weinrauch makes is a .25 caliber.
Good rifle, good caliber for most uses. Did you have a specific question?
At present the Sam Yang 50 Caliber "Dragon Claw". However this year 2014, other companies are starting to make 50 caliber air rifles. These rifles are capable of taking down deer.
Depends on what type of gun you are talking about. A pistol it is either .357 magnum or 44/40 Winchester which uses a rifle caliber size round in a six shooter for interchangeable use. Rifles would be 50 cal. m107 but the most effective round is a 416. The most powerful pistols are the Desert Eagle .50 caliber and the .500 Smith&Wesson
It is most likely to be a .32 caliber rifle since it uses .32 caliber ammo
There is no most powerful airsoft sniper rifle that you can just buy. But, Iv'e heard of guys tuning them over 800fps with custom parts. My most powerful is 600fps.
30/06