Red Dot questions

I’m setting up a Umerex Buckmark for my BIL eightieth birthday present. I’d like to put a red dot on it but I’ve never used one. I’ve looked online and see there are 2 basic types. One with a tube like a optical scope and open ones without a tube. Which is a better style for a low powered back yard plinker pistol? Any input will be helpful. I’m hoping to stay under $40 since it’s only a $45 pistol.
 
The open ones are usually more affordable. The closed ones (usually) more expensive and easier to keep clean.

If it's just a back yard plinker, you'll be fine with an open red dot. They both do the same job -- the only difference is the closed one (if well made) keeps the unit weather-sealed.

That said, go with whichever unit is of higher quality, given your $40 ceiling. Never know what's on sale. In this era of "everything is backordered", it's better to go with what is available rather than waiting 8 months for the perfect item to arrive.
 
Standard pistol no stock. The Umerex has a Weaver rail but I’ve read it still usually takes some filing to get a sight/scope mounted. I’m guessing someone didn’t get the mould quite right.
Reflex sounds like the way to go. I’ve seen several on eBay or Amazon for $25-40 with Weaver mount. I’m sure in that price range quality is minimal but killing adult beverage cans doesn’t require military spec.
I’m just starting to square the gun away but by my first evaluation I would say by 20 yards the drop will be too bad to reliably hit anything smaller than a 1960 Buick. So this will be a 3-15 yd gun.
 
I seem to see more reflex sites on pistols that I do the tube type red dots. I'm not sure why.

I thought that was mostly to do with lowering the weight on top of the slide. The heavier the red dot, the more reciprocating mass, the harder it is to keep the gun steady for a 2nd shot.

I doubt that is of a concern on an air rifle.
 
Some of the images of sights on eBay and Amazon appear to have a pink tint to the viewing window. Are the windows different colors depending on the coatings or is it just the images are colored? If they are different which color is better?

Generally you want as clear a viewing site as possible. The more colour, the less contrast you will see, i.e. the harder it will be to find your target.
 
For pistol I would say reflex sight and as small as you can get. And there is a difference between $$.00 and $$$.00 but all things being equal, ease of use trumps dollars. I spent about $60. on one from O.Planet (coupon and O bucks) for my little Crosman pumper. Has different reticles, the circle with dot is my favorite and helps me plink very accurately in my back yard.
 
In MOST of the dot sights, the screen tint NEEDS to be there. It's part of the "reflex" and, you...the viewer to be able to see the dot. Differing colors, and differing amounts of color. It seems the cheaper the sight, the more the lens color is noticeable.

Only the more expensive dot sights have a work around for the reflection.
The Holosun, the "newer" Trijicon, Leupold, newer Vortex, are some of the more clear lenses, but also more expensive.
Holosun has a few newer dot sights that the lens(s) are clear, or they have no "noticeable" color tint.

Note that the battery life also goes way up in the more expensive sights. Like in the 50,000hr range !
And if you...accidently drop you gun, and it lands on the sight, with a cheaper sight...you'll be buying a new one !

Mike
 
Hello if you are looking at the $40 price range look at the Truglo 30mm red dot sight can usually find them at Dicks sporting goods from $35 to $45 with 5 moa dot. Just realize that with a 5 moa dot at 25 yds the dot covers 1 1/4 inches. For the price it is not a bad sight at all(I have several on some of my better 22cal plinkers ) It is a little heaver than the open versions but a bit more robust. Hope this helps Eric