Spotting Scopes are used to see bullet holes in targets at ranges up to 200 yards. (I've never seen conventional a spotting scope that would reliably show 30 caliber bullet holes at 300 yards or over.) For offhand shooting you must be able to see 30 caliber bullet holes in the black at 200 yards under most conditions. This is the threshold requirement for a spotting scope, and spotting scopes either do the job or don't.

There are many cheap spotting scopes for sale that don't do the job. Don't buy one; you'll be disappointed.

I have two Bushnell Sentry spotting scopes, and I'll buy a better spotting scope when I find one. I've been looking through every spotting scope I can for a long time, and haven't found a better one yet.

Walter Deane (a very knowledgeable caster and reloader, most fondly remembered for inadvertently shooting a 44 caliber bullet through an entire closet of clothing), told me a long time ago that 20 power was all the magnification needed or usable in a spotting scope. Some days 30 power eyepieces do a better job, but for all around use, without changing eyepieces, Walter was right.

Since I wrote the above, I've read about some very good and very expensive spotting scopes such as Howa. These spotting scopes are reported to be wonderful. They cost in the neighborhood of $1000, a neighborhood that I don't visit very often.

For many years I shot in an offhand match every Sunday from Nov-Mar, from a heated shooting house, at 200 yards. Old Colony, Pembroke MA.

We use spotting scopes and look at/for every shot.

Most of the time I could see most of the holes, down to 30 caliber, in the black.

Most of the time I could see 22 holes in the white, many in the black.

Sometimes I couldn't see 45 holes in the white, and many holes smaller than 45 were not seen-black or white.

All with my 20X Bushnell Sentry

At this match, and whenever I've shot, till today, I ask to look through any spotting scope I'm not familiar with.

I'm still of the opinion that a 20X fixed power spotting scope is going to do the job as well as any other scope, most of the time.

Mirage will hurt any view, at any power I've looked through, even on cold days with a foot of snow on the ground. Everything wiggles around.

I don't know anything about seeing holes at ranges greater than 200 yards.

Spotting scopes I'm talking about must be in the feasible set. This specifically excludes the Unertl Team Scope and other scopes that are either very big or very expensive. There are Kowa scopes for $1200 or so, not feasible for most of the folks I know.

In order to do a comparison, it is necessary to set up a pair or more of scopes at the same range on the same day when there's a lot of mirage-start in the morning before the mirage, and have a set of folks look through them.

There has been a lot of talk on the CB-L about astronomical scopes, seems like both reflector and refractor.

But less a comparison = test, I don't know that any of these is "better" than another.

On a clear, calm, cool, sunny day without any mirage; my Sentry will allow me to count 22 holes at 200 yards-pretty well, and to accurately count 30 caliber holes. I suspect that many spotting scopes will allow the same.

But let it get dark or miragy and things go awry.

On bright sunny 90 degree days in Miami (last Wed.) I have a bit of trouble seeing 22 holes in the black at 100 yards!

I think that for now I'll stick with my story, since my opinion is based on 20+ years of observation of other scopes on the same day at the same place. And that opinion is:

A 20X Bushnell Sentry or ?? does the job most of the time, up to 200 yards, that any scope will do.\

More expensive (Kowa) or ?? maybe reflector?? scopes will do a better job some times.

The mount, keeping the spotting scope still, is extremely important. Keeping the scope steady requires a mount such as a good camera tripod or one of the Al Freeland foldable-unscrewable mounts. From the bench, various home made clamp on arrangements work well, as do the bought (expensive) clamp on mounts. The scope has to be still!.

 Variable power scopes seem to lack eye relief, and don't work as well as fixed power scopes.

20X is all you need, most of the time.

   Ned Roberts, in "The Muzzle Loading Cap Lock Rifle", (written in 1940), writes about spotting scopes. Here are some quotes from the chapter "Accessories and Equipment", page 124:

"I have yet to see any prism spotting telescope that can be purchased for $150 or less that gives as fine definition of the target at 200 or 220 yards as can be obtained with a high-grade draw-tube telescope having as power of 50 to 70. The English made "Lord Bury" telescope in 50 power is the finest spotting telescope that I have yet owned, and gives most excellent definition at all ranges."

A lot of years have gone by, the draw tube telescope is an instrument of the past, but I am interested in his comments about power of spotting scopes.

Roberts goes on to talk about a quote from "The Improved American Rifle", published in 1848, about a spotting telescope with a power of 77 times that allows seeing the head of a pin at 220 yards.

I've never tried to look at the head of a pin at 200 yards, or any such small thing. I think the background and light would have a lot to do with how well it could be seen. I have looked for and at 22 holes in the black and in the white on targets at 200 yards, and find that no matter the power of the scope, very favorable light and mirage conditions are required to see ALL of maybe 10 22 caliber holes in the black at 200 yards. And good light and mirage conditions must exist to see ALL of maybe 10 22 caliber holes at 200 yards, some of which are touching the lines.

I think that any telescope much above 30 power needs a very stable mount, and that probably a concrete bench or an extremely stable tripod must be used. Certainly the amateur astronomers must have mounts or tripods that would do the job.

Anyhow, this is what Ned said almost seventy years ago about spotting scopes.