Barra 1100z Power Tune Basics
In our review of the HAM Gold award-winning Barra 1100z PCP air rifle, we commented on that tempting hammer spring adjustment screw. Now we’re using it as we bring you Barra 1100z power tune information. You’ll likely find this useful as basic data that helps you tune your own 1100z…
The hammer spring adjuster is the only built-in method of adjusting the 1100z’s power (except for shooting at different HPA fill pressures, of course). However, it can produce some significant changes in the gun’s Muzzle Energy and shot count as we’ll see.
Basically, it’s impossible to properly tune any air rifle without using a Chronograph. However the information given in this article should give you some basic information to make a sensible Barra 1100z power tune, even without a chrony.
Base Data – Factory Tune
For this test, I started with the shootdown chart that was produced as part of the 1100z HAM review. This is an essential step for any tune. If you don’t know the performance of the gun in factory condition, it’s impossible to know if your changes are making an improvement or not!
As we can see, the factory tune produces 30 consistent shots (with an Extreme Spread of 40 FPS) at an average Muzzle Energy of 26.01 Ft/Lbs when using H&N Baracuda 18 pellets. (We know from HAM testing that these pellets actually weigh 18.25 Grains and have calculated the powers accordingly).
Barra 1100z Power Tune – Adjuster Half A Turn In
By rotating the hammer spring adjuster half a turn in, we would expect to see an increase in Muzzle Energy, combined with a reduction in consistent shots. And that is indeed what does happen!
As the chart shows, now the number of consistent shots has dropped by 33% to 20. In return, the Muzzle Energy has increased by 11% to 28.94 Ft/Lbs, when using the same pellets.
Barra 1100z Power Tune – Adjuster One Turn In
Let’s go another half turn in!
Now – surprisingly – we have 23 consistent shots at 29.35 Ft/Lbs using the Baracuda 18s.
Barra 1100z Power Tune – Adjuster 1.5 Turns In
Going 1.5 turns in on the power adjuster, we see another increase in power, together with a very similar number of shots.
Now we have increased the Muzzle Energy by 14.2% to 29.70 Ft/Lbs, still using the H&N Baracuda 18 pellets.
Barra 1100z Power Tune – Adjuster Two Turns In
Finally, we have increased the power by 20% over the factory settings with 31.25 Ft/lbs of Muzzle Energy. The price to be paid is that we have just 12 consistent shots with an Extreme Spread of 40 FPS. It’s al downhill from there, as you can see…
Barra 1100z Power Tune Summary
Now let’s put all those tune results onto one chart. WOW!!!
Yes, it’s confusing, however we can see a comparison of the changes made by the hammer spring adjuster settings. Note that the Muzzle Energy is close to identical for all the tunes at shot 23!
So let’s take a different look at our Barra 1100z power tune results…
As a result of this testing, I would say that the standard factory settings provide a good balance of power and shot count.
However, If I was going to increase the hammer spring tension on this Barra 1100z, I would go in 1 or 1 1/2 turns from the factory setting. This will give you more than 20 shots with an Extreme Spread of 40 FPS and a power level of close to 30 Ft/Lbs with H&N Baracuda 18 pellets.
Of course, each individual gun will be slightly different and the results differ depending on the pellets you are using.
But one thing’s for sure, cranking the 1100z’s hammer spring tension screw right in is not likely to be a successful strategy. Sure, you’ll achieve more power, but for a vanishingly-small number of shots. A more nuanced approach is probably best, definitely with the assistance of a Chronograph.
