Brocock Compatto Air Rifle

Brocock Compatto .22 FAC, part 2 of 3.

This is the second part of a full test I did using a Brocock Compatto belonging to Roger McMinn in Victoria to whom I am extremely grateful. This Compatto was used to do the 3 Power Level Tests and the Power Decay Tests so that all the results are relevant and not compromised by using different air rifles.

Brocock Compatto PCP

Brocock Compatto

The Pellets Tested in the Brocock Compatto.

For all these tests the initial sighting in was done with Baracuda pellets and from then on no adjustments were made unless noted. This gives a comparison between pellets in this air rifle that we wanted to achieve. I have used the same types of pellets in all 3 pellet/power tests as can be seen below.

These second power results were obtained in a temperature of 21.5 degrees C, a humidity of 28% and a cross-wind left to right varying between 10 and 22 kilometres an hour at an altitude of 30 metres above sea level.

I have put the original High Power Targets on the left for comparison and the results in brackets for the High power level.

H&N BARACUDA (21.4 Gr x 5.50mm)

H&N Baracuda

(Full Power)

JSB Exact Jumbo Heavy

Medium Power

Standard Deviation(2.7) 5.2 Ft
Highest Speed(751.5) 716.6 F/S
Lowest Speed(743.8) 702.4 F/S
Extreme Spread(7.6) 14.1 Ft
Average Speed(747.9) 708.2 F/S
Energy(26.26) 23.84 Fpe


JSB EXACT JUMBO HEAVY (18.13 Gr x 5.52mm)

H&N Terminator

(Full Power)

H&N Field Target Trophy

Medium Power

Standard Deviation(3.8) 3.6 Ft
Highest Speed(806.5) 776.5 F/S
Lowest Speed(794.5) 765.7 F/S
Extreme Spread(11.9) 10.7 Ft
Average Speed(800.5) 773.5 F/S
Energy(25.80) 24.09 Fpe


H&N TERMINATOR (16.36 Gr x 5.50mm)

H&N Baracuda Power

(Full Power)

JSB Exact Jumbo

Medium Power

Standard Deviation(11.8) 10.7 Ft
Highest Speed(807.6) 760.8 F/S
Lowest Speed(773.6) 729.5 F/S
Extreme Spread(33.9) 31.3 Ft
Average Speed(794.0) 745.3 F/S
Energy(22.91) 20.18 Fpe


H&N FIELD TARGET TROPHY (14.66 Gr x 5.53mm)

H&N Baracuda Hunter

(Full Power)

H&N Hornet

Medium Power

Standard Deviation(9.4) 8.5 Ft
Highest Speed(870.3) 803.2 F/S
Lowest Speed(844.2) 779.9 F/S
Extreme Spread(26.1) 23.3 Ft
Average Speed(859.3) 788.5 F/S
Energy(24.04) 20.24 Fpe


H&N BARACUDA POWER (21.14 Gr x 5.50mm)

H&N Hunter Extreme

(Full Power)

JSB Ultra Shock Heavy

Medium Power

Standard Deviation(6.8) 3.7 Ft
Highest Speed(710.3) 663.5 F/S
Lowest Speed(688.9) 652.6 F/S
Extreme Spread(21.3) 10.8 Ft
Average Speed(696) 658.0 F/S
Energy(22.8) 20.33 Fpe


JSB EXACT JUMBO (15.90 Gr x 5.52mm)

JSB Exact Jumbo Monster

(Full Power)

H&N Baracuda Green

Medium Power

Standard Deviation(3.3) 6.3 Ft
Highest Speed(843.1) 794.4 F/S
Lowest Speed(834.2) 773.6 F/S
Extreme Spread(8.9) 20.7 Ft
Average Speed(837.7) 784.7 F/S
Energy(24.78) 21.75 Fpe


H&N BARACUDA HUNTER (18.21 Gr x 5.50mm)

Compatto Target #1

(Full Power)

Compatto Target #2

Medium Power

Standard Deviation(4.6) 5.2 Ft
Highest Speed(797.9) 769.4 F/S
Lowest Speed(784.7) 754.2 F/S
Extreme Spread(13.2) 15.2 Ft
Average Speed(790.8) 760.5 F/S
Energy(25.29) 23.39 Fpe


H&N HORNET (16.Gr x 5.50mm)

Compatto Target #3

(Full Power)

Compatto Target #4

Medium Power

Standard Deviation(7.0) 6.3 Ft
Highest Speed(830.6) 785.9 F/S
Lowest SpeedNULL
Extreme Spread(19.1) 17.5 Ft
Average Speed(822) 773.2 F/S
Energy(24.01) 21.15 Fpe


H&N HUNTER EXTREME (19.09 Gr x 5.50mm)

Compatto Target #5

(Full Power)

MTC Viper Pro

Medium Power

Standard Deviation(7.6) 10.9 Ft
Highest Speed(802.5) 706.0 F/S
Lowest Speed(780.5) 676.2 F/S
Extreme Spread(21.9) 29.7 Ft
Average Speed(793.2) 692.2 F/S
Energy(26.68) 20.32 Fpe


JSB ULTRA SHOCK HEAVY (25.4 Gr x 5.52mm)

(Full Power)

Medium Power

Standard Deviation(4.1) 4.5 Ft
Highest Speed(657) 640.4 F/S
Lowest Speed(646.3) 628.1 F/S
Extreme Spread(10.7) 12.2 Ft
Average Speed(651.9) 634.1 F/S
Energy(23.97) 22.68 Fpe


JSB EXACT JUMBO MONSTER (25.4 Gr x 5.52mm)

(Full Power)

Medium Power

Standard Deviation(4.1) 4.5 Ft
Highest Speed(657) 640.4 F/S
Lowest Speed(646.3) 628.1 F/S
Extreme Spread(10.7) 12.2 Ft
Average Speed(651.9) 634.1 F/S
Energy(23.97) 22.68 Fpe


H&N BARACUDA GREEN (12.35 Gr x 5.50mm)

(Full Power)

Medium Power

Standard Deviation(7.2) 2.9 Ft
Highest Speed(916.3) 876.6 F/S
Lowest Speed(897.2) 868.1 F/S
Extreme Spread(19.1) 8.5 Ft
Average Speed(904.55) 872.3 F/S
Energy(22.44) 20.87 Fpe


These target results above are what one could term “scruffy” that has been bought about by 2 factors, one was the increase in wind speed and the other was the reduction in pellet speed. In saying that, it is interesting to note that the heavier pellets did in fact perform pretty well with the reduction in speed in windy conditions. The JSB Exact Jumbo and JSB Exact Jumbo Heavy pellets performed pretty well in both the full and medium power settings on the Compatto.

I will be doing a tuning article on the Brocock Compatto shortly and will show you how to improve the groups in any particular power setting, though it is very difficult, if not impossible, to get a one pellet to shoot well in all power settings. You can of course find a couple of pellets that will perform across the three power modes.

Compatto Energy Decay Test in Medium Power Mode.

Doing a Pellet Energy Decay Test in Medium Power Mode is done exactly as per the high power mode. Essentially I am looking at what advantages there are in this power mode, how many shots to a ‘fill’ and what speed/power figures we are to expect.

When we look at the following targets where I have shot 10 shots into each target until the pellet drop was noticeable, we see that the JSB Exact Jumbo Heavy pellet performs well at the mid power level too.

1st of the 10 Shot Groups starting off with a full cylinder at 200 Bar.

For the 10 shots in these 1st targets the Chronograph gave me the following results at the High power setting and the Medium Power setting:

High Power 1-10 Shots

Standard Deviation 4.2 Ft
Highest Speed 808.4 F/S
Lowest Speed 792.7 F/S
Extreme Spread 5.6 Ft
Average Speed 799.9 F/S
Energy 25.76 Fpe


Medium Power 1-10 Shots

Standard Deviation 5.7 Ft
Highest Speed 786.5 F/S
Lowest Speed 769.2 F/S
Extreme Spread 17.3 Ft
Average Speed 779.6 F/S
Energy 24.47 Fpe


Following are shots 11 through to 20 below.

For the 10 shots in these 2nd targets the Chronograph gave me the following results:

High Power 11-20 Shots

Standard Deviation 2.7 Ft
Highest Speed 815.3 F/S
Lowest Speed 804.2 F/S
Extreme Spread 11.0 Ft
Average Speed 811.2 F/S
Energy 26.50 Fpe


Medium Power 11-20 Shots

Standard Deviation 4.6 Ft
Highest Speed 793.6 F/S
Lowest Speed 780.5 F/S
Extreme Spread 13.1 Ft
Average Speed 786.67 F/S
Energy 24.92 Fpe


Shots 21 through to Shot 30 Below.

High Power 21-30 Shots

Standard Deviation 10.0 Ft
Highest Speed 804.9 F/S
Lowest Speed 772.3 F/S
Extreme Spread 32.6 Ft
Average Speed 788.5 F/S
Energy 25.0 Fpe


Medium Power 21-30 Shots

Standard Deviation 6.1 Ft
Highest Speed 785.9 F/S
Lowest Speed 768.2 F/S
Extreme Spread 17.7 Ft
Average Speed 774.6 F/S
Energy 24.16 Fpe


Shots 31 through to Shot 40 Below.

High Power 31-40 Shots

Standard Deviation 21.8 Ft
Highest Speed 767.9 F/S
Lowest Speed 699.0 F/S
Extreme Spread 68.9 Ft
Average Speed 736.6 F/S
Energy 21.85 Fpe


Medium Power 31-40 Shots

Standard Deviation 13.0 Ft
Highest Speed 773.3 F/S
Lowest Speed 730.2 F/S
Extreme Spread 43.0 Ft
Average Speed 751.6 F/S
Energy 22.75Fpe


Shots 41 through to Shot 48 & 50 Below.

High Power 41-48 Shots

Standard Deviation 32.9 Ft
Highest Speed 695.9 F/S
Lowest Speed 590.6 F/S
Extreme Spread 105.3 Ft
Average Speed 647.3 F/S
Energy 16.87 Fpe

Medium Power 41-50 Shots

Standard Deviation 19.9 Ft
Highest Speed 725.0 F/S
Lowest Speed 662.9 F/S
Extreme Spread 62.1 Ft
Average Speed 696.3 F/S
Energy 19.52 Fpe


The Power Decay rate in Medium Mode in the Brocock Compatto gives better grouping at a reduced cylinder air pressure than is achievable in High Mode. It should be NOTED here that this test is of a brand new rifle straight out of the box without any tuning, hammer spring adjustment or customising. Further to this, I should point out that all the 6 shot targets are shot under 30 seconds and the 10 shot targets are shot under 1 minute and in temperature and windy conditions not unlike what we find when shooting.

So should you sort your pellets, then bench-rest the air rifle taking your time, I would expect that Blind Freddy should achieve better results than I have done here. To me this is not a competition and so I snap-shoot these tests so as not to take up time (that I don’t have) and give you easily achievable results that still tell the story. Still, you need to mount a GOOD Scope on the Compatto like one of the MTC Scopes, namely the MTC Viper-Pro or a Hawke Sidewinder. The name of the game is being actually able to see a target before you can get around to hitting it, so steer clear of some of the cheap scopes with wire reticles (as opposed to quality etched glass reticles that are thinner) coming out of China un-branded. Sure, some are quite good, given 90% are made in China but there is a lot of crap out there and they way they get rid of it, is to sell it cheap to those clowns that buy on price only. (I guess I will get a few comments after that…)

MTC Viper Pro

MTC Viper Pro


The Graph below shows the individual shots from start to finish in both Energy (Fpe in Red with Scale on the RIGHT of the Chart) and Speed (F/S in Blue with the Scale on the LEFT of the Chart).

Compatto Energy Chart

Energy and Speed Decay Chart for the Brocock Compatto in .22 cal in the Medium Power Setting.

Now it’s all very well discussing the speed in the Medium Power Setting but to get a true comparison between High and Medium I have put both settings on the one graph. The BLACK line is the HIGH Power Setting designated (Speed H) while the Medium Power Setting is (Speed M) in Blue along with its graph line.

Compatto Speed Chart

If you follow either line you will see that they cross over at around the 30 shot mark. This is due to the High Power setting using more air than the conservative Medium Power setting. When we tune the Brocock Compatto you will see that the hammer spring pressure will vary this cross-over point and when fitted with a Huma PCP Regulator we will end up with a very different graph indeed. Furthermore, and more importantly, we will make better use of the available air and this will be reflected in the grouping results.

Pictured below are 2 Huma Regulators for the Brocock Compatto set at FAC power rating.

Brocock Huma Regulators

Huma Regulator for Brocock Compatto .177 & .22 FAC

Summary on the Brocock Compatto in Medium Power Mode.

This semi-Bullpup Compatto becomes a very useful tool in the hands of a hunter or vermin controller due not only to the ergonomics of the ladder frame, but to the variable power settings. When set up and used correctly, these variable power settings open up different avenues available to the hunter that are not available when using many of the single power PCPs that are around today. No longer are PCP air rifles “too powerful” for a particular scenario such as shooting in a shed or at close quarters as the operator can ‘dial down’ the power at will. The same applies when more power is needed and so on.

Hunter with Compatto

Hunter with a Compatto

Target shooters are not forgotten as Field Target Competition shooting calls for knock-down targets at varying ranges. Given the light weight of the Compatto, shooting does not need to be done in the prone position or bench-rested as is the case with many of the heavy air rifles of today.

Below is my Brocock Compatto with a large Hawke Sidewinder, bi-pod and Air-Stripper that can put pellets right where you want them. It is not often that one sees a scope on a rifle that costs around the same price as the rifle it is mounted on. This just goes to show that they both combine to give accuracy that until now was the domain of PCPs 2, 3 and 4 times the cost of the Compatto.

Compatto with Hawke Sidewinder

Compatto and Hawke Sidewinder ED 10-50×60

I am only halfway through the testing of the Brocock Compatto and can say with confidence that this PCP air rifle will in all likelihood be my largest selling air gun, as it sells itself once picked up and shouldered, Amen.

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