397 with new stock
Benjamin 397 with my new curly maple stock.

Part 1
Part 2
Part 3
Part 4
Part 5
Part 6
Part 7
Part 8
Part 9

This report covers:

  • The 397 open rear sight
  • BB learned more!
  • The Williams 64 peep sight
  • What does this sight fit?
  • Talk about easy!
  • Remove the rear sight
  • BB learns even more!
  • Summary

Today I mount the Williams 64 peep sight to my Benjamin 397 with the pretty curly maple stock. Guys, I learned a lot today!

The 397 open rear sight

In Part 9 I told you I was going to mount the Williams sight when it came in. And of course that meant that I had to remove the rear sight that was on the 397, because the Williams sight would look right through the open notch of the factory rear sight when it was sighted in. I did think I could lower it out of the way but today I discovered that was impossible.

I dreaded taking the sight off, until I examined the 397’s rear sight closely. I saw that it was attached to a base and Crosman had made the four flanges on the springy legs that hold the sight in place short, so they wouldn’t put much strain on the soldered barrel joint when the sight was removed.

397 rear sight
As you see, the 397 rear sight legs are short, so they don’t put too much pressure on the solder joint as they come off the rifle.

I will now compare that rear sight to the one on my Sheridan Blue Streak from 1978.

BB learned more!

I was not aware until writing this report that the Sheridan rear sight also clamped to a separate mount and not directly to the barrel. I have owned that rifle for 43 years since it was new (and I was also a lot newer) and I had heard so many stories of the rear sight breaking the solder joint when it was removed that I just accepted that the clamp was direct to the barrel.

Sheridan rear sight
The flanges on the Sheridan rear sight legs run the entire length of the sight.

But you do need to take caution, because removing that sight is the number one cause of the barrel solder joint breaking. I guess the longer clamping surface is responsible, or maybe some guys just put Vise Grips on the sight and pull it off. I don’t know the reason, but I do know removing that sight can break the solder joint.

The Williams 64 peep sight

The Williams company makes sights of all kinds. This peep sight is not made to fit any particular firearm or airgun, but many of them can be adapted to fit it. Because of that, it doesn’t come with directions. It’s very simple and straightforward to install, but don’t look for the directions. However I am going to show you how I got it to fit this 397.

397 sight holes
The Benjamin 397 (and 392) has a flat on the right side of the round receiver. Two holes are drilled and tapped to receive the screws that mount the Williams 64 sight.

What does this sight fit?

The Pyramyd Air website says this sight will fit rifles made in the last five years. Well, I know that the description has said that for several years, so the guns it will fit go back farther than just five years, but how much farther I can’t say. Don’t take chances. If your airgun is older, call the Pyramyd Air tech department and ask whether this sight will fit. If you just bought a new airgun the sight should fit, no problem.

397 Williams 64
This is what comes with the sight.

One mounting screw comes separate from the sight. The other one is under the elevation slide on the right side of the sight.

397 Williams 64 back
Here is the sight on its back. The screw poking through is under the elevation slide.

397 Williams 64 slide off
Loosen the screw on the right with the silver ring around it and the elevation slide slips up and off, revealing the other mounting screw.

Shop PCP Rifles

Talk about easy!

I had the sight on the rifle in seconds. Then I slipped the elevation slide back down and tightened the jam screw on the right.

397 Williams 64 mounted
And there is the sight, mounted!

Now I brought the rifle to my shoulder and looked through the peephole. The hole was almost perfectly aligned with the rear sight notch. It was maybe off to the right just a little. Yes, the rear sight leaf is elevated a little, but I could see that even if it was all the way down it would still be in the way of the peep.

Remove the rear sight

Now I came to the part of this job that I had been dreading — removing the rear sight. It appeared that just tapping it with a soft rubber hammer was the way to proceed, so I did. And it was!

397 rear sight coming off
I tapped on the front of the rear sight with a rubber hammer and it slid back easily. Four or five taps got it to here.

397 rear sight off
The rear sight came off without any problem.

BB learns even more!

After the rear sight was off, BB learned one more thing. The “base” he has been talking about isn’t a base at all! It is a pair of triangle-shaped individual grooved inserts that tuck into the barrel/pump tube gap and allow the flanges on the legs of the rear sight to ride in their grooves. They are held in place by the spring pressure applied by the rear sight legs. It’s an ingenious way of mounting the rear sight. And, when BB examined his 1978 Sheridan, he discovered that it has the exact same inserts. But that sight has a solid sight flange on each side that isn’t as delicate as the one on this 397.

397 rear sight inserts
Those two inserts tuck into the gap between the barrel and pump tube — one on either side. They accept the flanges on the base of the rear sight legs.


This job took me about an hour because I stopped to take the photographs. Removing the rear sight was the most tedious until I realized that it was made to come off. Yes, BB did learn a lot today, and the design of the new rear sight with it’s shorter flanges is an improvement worth mentioning.

397 finished
The finished rifle with the peep sight mounted and the rear sight removed looks sharp!

Next time I will sight her in and see what kind of accuracy she has. Remember — I’m still looking for the best pellet for this rifle!