The DIY Hunter

Benjamin 397 Pellet Rifle with Bushnell 4-12x Scope

I purchased a Benjamin 397 pellet rifle a few years back and it has been a nice rifle. This past winter I decided to see what it could do accuracy wise. I had some unwanted pests raiding the bird feeders and I wanted to be able to place a pellet on a quarter sized target at 30 yards. Could it be done? I had to know.

I started by tuning up the trigger using Airgunsmith's advise. This did wonders to the trigger pull. I then wanted a variable power scope. Almost all 3-9x scopes have a fixed parallax that would cause a lot of accuracy problems due to the parallax issues at various ranges. I decide to go with a Bushnell Banner 4-12x with an adjustable objective.  With this rifle scope I can adjust the parallax from 10 yards and out.

I did have a issue with the bases and rings being loose. This took me a while to figure out. It was caused by having the rings clamped towards one end of the base creating leverage on the base that made it loose. I had to clamp the ring centered over the rear base. They're a little tricky so just keep an eye on the bases to make sure they are not loose around the barrel.

Pellet Accuracy Test Target from Benjamin 397

Best Pellets for a Benjamin 397

This left one problem, eye relief. The scope is mounted too far forward to get your head into position to view through the scope. The Benjamin 397 pellet rifle comes with a fairly lengthy trigger pull for an air rifle and the scope is mounted on the barrel not on the receiver.  I tried mounting the scope as far back as I could given the location of the bases but I found  two problems. One, I had to mount the ring in the center of the base to keep it solid. And two, if the scope was any further back it would interfere with the bolt handle unless I used some really high rings.

Gamo Rocket .177 Pellet

Gamo Rocket .177 pellet — my favorite pellet for my Benjamin 397 pellet rifle.

My solutions was to cut the stock down. I cut an inch off the end of the stock, placed the butt plate back on, sanded the stock and butt plate to fit, and then stained the area as best as I could to match the current stain. I still think I need to take another inch off the stock for optimal comfort with the eye relief and this scope but, as is, it works pretty good.

Now to find out what pellet shoots the best. I tried six different pellets available from the local Walmart and sporting goods store. The Daisy #557 pellets I used were some old pellets that I had and I can not find them any more.

Gamo Rocket and TS-10 pellet accuracy

Two five shot groups. One with Gamo Rocket pellets and the other with Gamo TS-10 pellets.

If the Gamo Rockets shot well I figured that the Gamo TS-10 Long Range pellets would be even better. Well, as you can see from the target they don't shoot very good from my Benjamin 397.

Here are the pellets I tried.

  • Daisy, #557
  • Savage Arms, Model 8512
  • Gamo, Rocket
  • Daisy, Precision Max
  • Daisy, Pointed Field
  • Gamo, Red Fire

My shooting range for my tests came from standing in the bathroom, shooting out the window into a piece of plywood against the backyard fence. I did use a large sand bag in the window to steady the rifle. I'm pretty confident I could get the groups a little tighter if I shot from a bench. However this was exactly where I was going to be working on the pest control so, out the bathroom window I conducted the test.

As you can see from the targets the Gamo Rocket .177 caliber pellet was the clear leader in accuracy from my Benjamin 397 pellet rifle. Again, the pellets I shot were only the pellets available at local sporting goods stores in my area. I'm thinking of ordering some Gamo Hunter pellets from and give them a try. I'm thinking these pellets might also shoot well.