Saturday, June 4, 2016

Air pistol tests

Saying in German: "Wer misst, misst Mist!" (English: "The one who measures measures crap").

But anyway... Today invested time to get to know how good/bad my cheap hobby air pistol ammunition is.

Vice. Combro chronograph. Three different ammunition. Two different pistols.

My tests say almost nothing. It is important to understand. Results may vary from pistol to pistol of the same model. Too many components are involved.

Your results with your guns will be different. That's life...

Steyr LP10E 10 shots

Feinwerkbau P 8X 10 shots

Tested ammunition:

  • H&N Final Match LG (Air Rifle) 4,49mm
    Average head diameter = 4,472mm
    Average weight = 0,531gr
  • Holme Premium LG & LP (Air Rifle and Air Pistol) 4,50mm
    Average head diameter = 4,437mm
    Average weight = 0,519gr
  • JSB Match Light Weight 4,50mm
    Average head diameter = 4,463mm
    Average weight = 0,499gr

Average values calculated after 10 random tests.

Holme Premium is my training ammo. Price about 6€ per 500. (who makes ammo with "Holme" label? RWS?)

What I have noticed. Head diameter deviation is almost the same for all three types of ammo. The weight - also similar deviation. Deviation graphs are really almost the same for all three ammo and are not interesting here.
But what makes JSB so stable (flat velocity line)? Obvious answer for now - weight. Lower weight causes higher velocity. Higher velocities have smaller deviation (in our case)?

Best groups (10 shots) were:

  1. JSB + LP10E
    Holme + P 8X
    (equal size... about 1.66mm center-to-center)
  2. JSB + P 8X
  3. H&N + P 8X
  4. Holme + LP10E ***
  5. H&M + LP10E
*** - The group was very tight with one "flyer". Without that "flyer" the group would be positioned also on the first place. Preparing values for deviation calculation I have noticed that some Diabolos are heavier... 0,513... 0,517... 0,515... 0,530! Etc... I think such "irregular" weight caused that "flyer".

It is easy to get good groups with H&N too. But we have to increase the velocity.

Thursday, June 2, 2016

P 8X Trigger

Played with the trigger settings a little bit.
Set about 80% of the weight for the first stage and the rest for the second stage. Straight forward manual for everyone.

After all I noticed a pin made of Neodymium (magnet). It "catches" and holds the sear after release (that sear holds the hammer). Clear trigger feeling. Short second stage. Minimal after-travel. No bouncing parts.

Strong Neodymium natural magnet

Feinwerkbau P 8X

Some infos and photos.

Weight specs (+/-):
  • Grip + main frame + naked barrel: 686g
  • Barrel shroud: 26g
  • Aluminium compensator + steel front sight: 18g
  • Steel comp + steel front sight: 42g
  • Air tank: 210g
  • Weight block for the barrel shroud: 14g (one item)
Tested pistol delivered with two comps - steel and aluminium.
Some weights.

Intelligent mounting rail for weights. Weights are different. Symmetrical (left/right).  

Barrel shroud without mounting screws. It "sits" simply there pushed back by comp and over. Good.

Trigger guard - kind of plastic but good quality.

Very qualitative rear sight I would say...

Comp with two mounting screws on the top.

Trigger shoe. Rotation in any direction possible (ball joint).

Six adjustment screws.