Tires: trailer tires seem low, Trailer Tires

Question
I recently purchased 2 new Carlisle Radial Trail ST205/75R14 tires for my single axle 19' boat trailer. They are load range C tires. I've checked the pressure with two different tire gauges (50 lbs.)but they look under inflated with a lot of flex in the sidewalls. I haven't taken the trailer anywhere yet and am wondering why it looks like this( the last tires were load range C also)and if I return these tires, which tires would be better?

Answer
Stace,

Trailer tires are allowed to have more deflection - and pretty much this is all controlled by the inflation pressure and has very little to do with the brand.

I would suggest you weight the trailer fully loaded - with everything you can possible think you might ever put in the boat.  Then compare that to the load carrying capacity of the tire.  I think trailer tires ought to have a 15% unused capacity.  Put another way, for safety reasons less load is better, and I think 85% of the rated capacity is the appropriate value.

*******************

Additional thought:

You are reemitted to use up to 10 more psi on trailer trailer tires for more speed capability.