Help with adjusting shims on Beretta Extrema II

[Nikon Shooter]

Hello,

I was wanting to get my Extrema II shooting a little higher, so I changed the stock shims.... I achieved the desired pattern height, but now I am shooting about 6" left of center (about 6"-8" high, which is what I was wanting).

I shot the gun this morning two times and let a friend shoot it once, and all three shots (new paper each shot) was high and about 6" to the left... The height is great, just can't figure out how I have got it shooting to the left.

I used the C-50 DX plastic shim in the front with the C-50 DX facing the butt end of the gun (thin side toward the top and thin side toward the right) and inside the stock I used the metal spacer also with the C-50 DX facing the butt end of the gun (that positions the hole low and to the left).

This should be the correct way to set the shim/spacer I thought, but perhaps I am mistaken???

Just curious if anyone has any ideas how I ended up shooting to the left, or how to get it centered back up?

If it matters we were shooting Kent Fasteel 3 1/2" number 4 shot through a Patternmaster extended tube at about 20yds.... This combo was shooting good, although a little too flat for me before the shim/spacer adjustment.

Thanks for your time!

 

[Pete409]

Nikon Shooter,

It sounds like you are doing it the correct way. The "C-50 DX" should be at the top and facing you as you look at the shim/spacer from the rear of the gun.

Perhaps you just weren't getting your cheek down on the gun firmly enough when doing the pattern placement testing. Or, perhaps you just jerked the trigger a bit in anticipation of recoil.

You might try it with some milder recoiling loads, although the pattern placement could be a little different with different loads.

Also, the choke tube used could make a difference if it were not drilled perfectly concentric with the bore.

My suggestion is to just make sure you did everything the way you said you did and then be careful in shooting the gun that you keep your cheek firmly on the stock and don't jerk the trigger.

Good luck and let us know what you find.

 

[mswestfall]

Assuming that you are a right handed shooter....

The DX designation is a "Cast-off" stock. If you replace the SX with a DX you may move the patter from "Cast-on" to "Cast-off" or move the pattern to the RIGHT.

That being said: How you see down the barrel is what I would think effects the left-to-right impact. Do you see the same left-to-right alignment?

It sounds to me like you have a problem independent of the shims.

What other info can you give?

 

[Nikon Shooter]

Thank you both very much for replying!

I meant to get back to this sooner, but with the holidays and duck season opening, I've been a little busy...

I am a right-handed shooter (hence the DX shim being used) and after convincing myself that I had done everything correctly (installing the shims) I decided to install the other shim included with the gun. This time I used the 55DX shim. The 60DX shim was installed from the factory.

After getting it installed, I took it out for another try (both times shooting the gun was from approx. 20yds and with the use of a steady rest).

I had also considered that it was possibly the aftermarket tube (although I have never had any issues in the past with a Patternmaster tube) or maybe even the shells. I fired four shots this time, 2 with the P-Master and 2 with the factory supplied modified tube. Each tube fired one Kent Fasteel 3 1/2" shell, and one 3" Winchester Drylok.

The results this time were much more satisfactory... The gun still shot slightly high, and all four shots were centered much better.

I can only conclude that the 50DX shim is what was causing trouble... When time permits I am going to try playing with it a little bit more and seeing if I can get it centered up a little better.

Again, thank you both for your time and suggestions!