What is a 20mmm picatinny rail?

[DsrtRat]

I have seen a few adds here and there referring to 20mm picatinny rails. Is that the same as a normal picatinny rail? From the diagrams of picatinny rails, they are not 20mm.

 

[Ryan j]

I think you/they mean 20 MOA...

A 20 MOA rail is lower at the front than the back.

With your scope at it's internal zero and mounted on a 20 MOA rail the point of impact at 100 yards will be 20 MOA high.

In other words the scope is pointing down relative to the barrel.

 

[DsrtRat]

In this case they are not. It is usually talking about rings/mounts that "fit 20mm picatinny rails".

I have been looking for a set of rings with a picatinny rail on top to mount something on top of a scope. I have seen several references to rings that will fit standard 20mm rail.

Is this paintball/airsoft thing by chance? Normall pic rail is slightly wider than 20mm at it's widest spot. They also describe the rings as accepting 25mm and 30mm scopes.

 

[Ryan j]

My bad...

I would imagine 20mm is the width of a standard Weaver/Picatinny Rail then.

 

[DsrtRat]

Not 100% sure about that. Here is a picture of a picatinny rail. 20mm = 0.787 inches.

Not sure if rings designed for 20mm rail would fit or not.

 

[DsrtRat]

Whoops, just realized this was in rimfire. Mad a fresh one in general to get more traffic and hopefully an answer.