Brocock Compatto

2. The Brocock Compatto .22 FAC, part 2 of 3.

This is the second part of a full test I did using a Brocock Compatto PCP 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 PCP.

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)

(Compatto PCP 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.

Brocock 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 PCP 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 PCP 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 Compatto PCP Huma Regulators

Huma Regulator for Brocock Compatto PCP .177 & .22 FAC

Summary on the Brocock Compatto PCP 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 PCP

Hunter with a Compatto PCP

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 PCP 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.

Brocock Compatto PCP 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.

Brocock Compatto

The Brocock Compatto .22 FAC Review part 3 of 3.

The Brocock Compatto Review part 3.

The Brocock Compatto Review is on again Guys, I have finally got around to finishing the 3rd part of this Compatto PCP review on the .22 calibre semi-bullpup. If you have followed along from part 1 to here then you will know that I am now putting up the results of testing the Compatto in Low Power mode.

It may be prudent to remind you that the gun used in this review was straight out of the box with no adjustments, modifications or accessorising in any way. The following are groups shot in each mode, with High Power on the left, Medium Power in the centre and Low Power on the right. This will save you the problem of scrolling back through the 1st and 2nd articles looking for a comparison. There is also a graph further into this article giving you a visual perspective of the 3 modes, their speeds in F.p.s. and Standard Deviations.

Brocock Compatto Side View

The Brocock Compatto Right Hand View showing the Power Level Knob on High in this Image.

The Brocock Compatto PCP Targets side by side.

H&N Baracuda Pellets are our testing pellets by choice as they are available in the 4 main calibres and generally speaking, provide a good all-round baseline for comparisons with other pellets. Those of you new to my articles and air rifle testing procedures please note that I do not normally adjust the scope or POA when moving from one pellet type to another or one target to another, that is the point of having a baseline.

I also try and shoot a complete test in one day as large variances in weather can throw out your results: this can be seen in the 1st article where I had to alter the scope on the 10 Shot Pellet Decay Test following a low group on the 1st target shot on the 2nd day. Academic in this case as I maintained my POA for the following 4 Targets when I could have run with all 5 groups low but still tight. With time being tight I did it this way that in hindsight may not have been the best choice as it does demonstrate the effects of weather from one day to the next. The wind during most of these test shoots was blowing from Left to Right and the impact of that can be seen in the results. All testing was done using a MTC Viper Pro 5-30×50 Scope.

H&N Baracuda (21.14 Gr x 5.50mm)

Power Levels HighMediumLow
Standard Deviation2.7 Ft5.2 Ft1.7 Ft
Highest Speed751.5 F/S716.6 F/S661.8 F/S
Lowest Speed743.8 F/S702.4 F/S656.6 F/S
Extreme Spread7.6 Ft14.1 Ft5.1 Ft
Average Speed747.9 F/S708.2 F/S659.2 F/S
Energy26.26 Fpe23.55 Fpe20.40 Fpe


JSB Exact Jumbo Heavy (18.13 Gr x 5.52mm)

Power Levels HighMediumLow
Standard Deviation3.8 Ft3.6 Ft2.0 Ft
Highest Speed806.5 F/S776.5 F/S711.4 F/S
Lowest Speed794.5 F/S765.7 F/S705.4 F/S
Extreme Spread11.9 Ft14.1 Ft5.9 Ft
Average Speed800.5 F/S773.5 F/S708.5 F/S
Energy25.80 Fpe24.09 Fpe20.21 Fpe


H&N Terminator (16.36 Gr x 5.50mm)

Power LevelsHighMediumLow
Standard Deviation11.8 Ft10.7 Ft3.5 Ft
Highest Speed807.6 F/S760.8 F/S711.8 F/S
Lowest Speed773.6 F/S729.5 F/S703.1 F/S
Extreme Spread33.9 Ft31.3 Ft8.7 Ft
Average Speed794.0 F/S745.3 F/S708.3 F/S
Energy22.91 Fpe20.18 Fpe18.23 Fpe




H&N Field Target Trophy (14.66 Gr x 5.53mm)

Power LevelsHighMediumLow
Standard Deviation9.4 Ft8.5 Ft4.4 Ft
Highest Speed870.3 F/S803.2 F/S759.2 F/S
Lowest Speed844.2 F/S779.9 F/S745.4 F/S
Extreme Spread26.1 Ft23.3 Ft13.8 Ft
Average Speed859.3 F/S788.5 F/S754.0 F/S
Energy24.04 Fpe20.24 Fpe18.51 Fpe


H&N Baracuda Power (21.14 Gr x 5.50mm)

Power LevelsHighMediumLow
Standard Deviation 6.8 Ft8.5 FtFAIL
Highest Speed870.3 F/S803.2 F/SFAIL
Lowest Speed844.2 F/S779.9FAIL
Extreme Spread26.1 Ft23.3 FtFAIL
Average Speed859.3 F/S788.5 F/SFAIL
Energy24.04 Fpe20.24 FpeFAIL

I would NOT recommend H&N Baracuda Power for use on LOW Power in the Brocock Compatto. They are a copper coated pellet and the manufacturer’s recommendations are a minimum power level of 12 Fpe (16 Joules). However, when we tested them in the Compatto we got very erratic results that stopped our testing in Low Power before we really got started.


JSB Exact Jumbo (15.90 Gr x 5.52mm)

Power LevelsHighMediumLow
Standard Deviation3.3 Ft6.3 Ft5.2 Ft
Highest Speed843.1 F/S794.4 F/S728.8 F/S
Lowest Speed834.2 F/S773.6 F/S712.9 F/S
Extreme Spread8.9 Ft20.7 Ft15.8 Ft
Average Speed837.7 F/S784.7 F/S723.4 F/S
Energy24.78 Fpe21.75 Fpe18.48 Fpe


H&N Baracuda Hunter (18.21 Gr x 5.50mm)

Power LevelsHighMediumLow
Standard Deviation4.65.28.0 Ft
Highest Speed797.8769.4660.9 F/S
Lowest Speed784.7754.2 635.7 F/S
Extreme Spread13.215.225.2 Ft
Average Speed790.8760.5651.1 F/S
Energy25.2923.3917.15 Fpe



H&N Hornet (16.00 Gr x 5.50mm)

Power LevelsHigh Medium Low
Standard Deviation7.0 Ft6.3 Ft1.3 Ft
Highest Speed830.6 F/S785.9 F/S725.8 F/S
Lowest Speed 811.5 F/S768.4 F/S721.8 F/S
Extreme Spread19.1 Ft17.5 Ft4.0 Ft
Average Speed822 F/S773.2 F/S724.1 F/S
Energy24.01 Fpe21.15 Fpe18.63 Fpe



H&N Hunter Extreme (19.09 Gr x 5.50mm)

Power LevelsHighMediumLow
Standard Deviation7.6 Ft10.9 Ft2.1 Ft
Highest Speed802.5 F/S706.0 F/S685.6 F/S
Lowest Speed780.5 F/S676.2 F/S 679.3 F/S
Extreme Spread21.9 Ft29.7 Ft6.2 Ft
Average Speed793.2 F/S692.2 F/S682.6 F/S
Energy26.68 Fpe20.32 Fpe19.76 Fpe


JSB Ultra Shock Heavy (25.4 Gr x 5.52mm)

Power LevelsHighMediumLow
Standard Deviation4.1 Ft4.5 Ft3.8 Ft
Highest Speed657 F/S640.4 F/S570.9 F/S
Lowest Speed646.3 F/S628.1 F/S559.2 F/S
Extreme Spread10.7 Ft12.2 Ft11.6 Ft
Average Speed651.9 F/S634.1 F/S566.4 F/S
Energy23.97 Fpe22.68 Fpe18.10 Fpe


JSB Exact Jumbo Monster (25.4 Gr x 5.52mm)

Power Levels HighMediumLow
Standard Deviation3.5 Ft2.9 FtFail
Highest Speed670.6 F/S659.2 F/SFail
Lowest Speed662.5 F/S650.5 F/SFail
Extreme Spread8.0 Ft8.6 FtFail
Average Speed 666.3 F/S652.9 F/SFail
Energy25.05 Fpe24.05 FpeFail

The JSB Exact Jumbo Monster while being the same size and weight (but not shape) as the JSB Ultra Shock Heavy just did not perform as the target testifies on low power. Remember, this is but ONE rifle straight out of the box, no barrel leading or beading in, no modifications or tuning and operating on 200 Bar and not the 240 Bar that Brocock now recommends for FAC Compatto PCP.

I used 200 Bar in this 3-part article as most of the filling systems that rely on Scuba bottles have the 232 Bar K valve that will only refill a 200 Bar rifle a few times and will not manage the 240 Bar limit. That said, I will be doing a test using 240 Bar as the recommended pressure and be comparing it with these results. This will allow you guys who are sitting on the fence so to speak, to make up your minds whether it is worth forking out the extra money for a 300 Bar Scuba bottle or HP Compressor for the extra performance that it will give you.

If I were to test the Compattos on 240 Bar, then many of you would cry ‘foul’ as I may have sold you a 232 Bar unit. At least this way with 200 Bar filling stations you can obtain accurate information and those of you who have budgeted for 300 Bar systems will soon get the chronographed results that you can expect from a 240 Bar fill.



H&N Baracuda Green (12.35 Gr x 5.50mm)

Power LevelsHighMediumLow
Standard Deviation7.2 Ft2.9 Ft6.2 Ft
Highest Speed916.3 F/S876.6 F/S780.8 F/S
Lowest Speed897.2 F/S868.1 F/S763.7 F/S
Extreme Spread19.1 Ft8.5 Ft17.0 Ft
Average Speed904.55 F/S872.3 F/S770.9 F/S
Energy22.44 Fpe20.87 Fpe16.30 Fpe

This H&N Baracuda Green Pellet is one of the lightest pellets in .22 calibre that I stock and as of now, has a very limited following. When looking at the targets you will notice that these pellets shoot a bit high at 25 metres yet group pretty well out of the box.

Those of you into tuning, I will be testing the Huma Regulator in a Compatto in the coming months and I am sure that this pellet will excel itself in accuracy and shot count. Those of you into target work, I think that should you weigh, sort, inspect and divide weights of these pellets, then try them lubed and un-lubed, you may well be on a winning combination in my view. I am working on an article (multi-part) on Pellet Selection for Tuning.


Brocock Compatto Review: Low Power Pellet Decay Test.


Shots 1-10

Shots 11-20

Standard Deviation2.2 Ft2.9 Ft
Highest Speed707.2 F/S703.3 F/S
Lowest Speed698.3 F/S 693.9 F/S
Extreme Spread8.8 Ft9.4 Ft
Average Speed702.4 F/S 699.5 F/S
Energy19.87 Fpe19.70 Fpe

The first target shows the first 10 shots from a 200 Bar fill and the second target shows shots 11-20 as we do the Pellet Decay Test here. The vertical and horizontal lines going through the Bull are used with the reticle cross hairs as finding the Bull after numerous shots becomes difficult when the Bull is obliterated.


Shots 21-30

Shots 31-40

Standard Deviation7.4 Ft9.5 Ft
Highest Speed696.1 F/S681.5 F/S
Lowest Speed675.5 F/S652.3 F/S
Extreme Spread20.5 Ft29.2 Ft
Average Speed687.0 F/S 666.6 F/S
Energy19.00 Fpe 17.89 Fpe

The LEFT target above shows shots 21-30 while the RIGHT target shows sots 31-40. As can be seen from the targets the groups are not that bad for low power considering that one would use this power mode for close up vermin control or just plinking. Whatever, this is LOW power that is not necessarily used when competition shooting though one could do with some selective tuning and practise in this mode.


Compatto PCP Pellet Decay Test.

Shots 41-50 in this last target shows a reasonable group but it has passed the Decay point and so finishes the Pellet Decay Test.

The Pellet Decay Test is a testing sequence where either I or Peter shoot a full air fill (only 200 Bar in this case) using the best performing pellet until the group drops 3 or more pellets out of the RED circle. This Decay Test is not an accepted air rifle test, it is a test that we felt demonstrated the usable shot placement that one could expect to get from a full fill.

I use only 10 shots per target so one can see the gradual decline in either the group or the pellet drop as the cylinder pressure drops.

When analysing this Brocock Compatto Review, in the Chronograph results I feel that not enough emphasis is put on the Standard Deviation / Extreme Spread. The Standard Deviation is a formula derived to show the mean average between each shot. I will cover this in an article on Pellet Tuning that I am currently writing. What IS IMPORTANT is the Extreme Spread as this tells you the separation distance between the fastest pellet and the slowest pellet.

Those of you new to this, if you measured the distance that the slowest and fastest pellets had traveled, you would find in this case on the right here, that the fastest pellet had in fact traveled 38.7 feet further in 1 second that the slowest pellet.

Standard Deviation12.4 Ft
Highest Speed658.5 F/S
Lowest Speed619.8 F/S
Extreme Spread38.7 Ft
Average Speed637.1 F/S
Energy16.34 Fpe

Note that the average energy of this Compatto PCP is 16.34 Foot Pounds (Fpe) and that equates to the power of many spring powered air rifles. The power and accuracy compare favourably with the Weihrauch HW100TK at a cost of about 25% less.


Brocock Compatto Review Shot Count Graph

The Brocock Compatto in .22 calibre with a Sling Shot Hammer fired in all 3 Modes: High in Green, Medium in Blue and Low Power in Red.

Brocock Compatto Review Extreme Spread Graph

As can be seen from the Graph image above, as the air pressure drops, so does the consistency of pellets while achieving close to the same feet per second. The ideal pellet will have a minimal Standard Deviation (SD) of less than 2.5 as that works quite well. On one occasion we have seen an SD of 0.0 with an Extreme Spread of 8” here over 10 shots. Effectively the pellets are travelling at the same speed with all 10 shots travelling very close to the same distance in 1 second. While very rare, having seen it I know it can be achieved with certain rifles if you put in the due diligence that is required when tuning.

Brocock Compatto Review:  Shot Count.

In a Brocock Compatto, any increase in power comes at a high cost in shot count as the cylinder is only 150cc. To achieve this shot-count the Brocock is fitted with an Inertia Hammer, aka Sling Shot Hammer that is not only effective as a hammer, but it also regulates the firing air charge efficiently.

In my view, an accurate Compatto PCP air rifle is a better choice than a more powerful rifle that lacks accuracy. In hunting I put accuracy above power and that is where you guys need to be going with your guns. Tune them so that they are accurate, then armed with this knowledge that you can hit what you are aiming at you can go hunting with effect.

You guys that are into vermin control I would seriously suggest that you take a good look at a Brocock Compatto PCP with its selectable power range. With vermin control you must be setup for multiple shooting environments, from open paddocks, bush, around houses and in warehouse and sheds. This fluid shooting environment requires different pellets as well as different power settings, hence the Brocock Compatto. With the Compattos’ short overall length, ladder frame stock of polymer construction you have a working tool of considerable durability and ease of handling.

If you are not into hunting, then a look at the targets from High Power down to Medium Power and that will show you that this Compatto PCP air rifle has the DNA required to be used competitively. With the adjustable power you also have the ability to practice in a confined place or just plink without going through copious amounts of air or putting holes in shed walls etc. The Compatto is available in .177, .22 and .25 calibres and as can be seen from this Brocock Compatto Review, this air rifle is fairly pellet consistent and will benefit from tuning and correct pellet management and selection.


Ian McIntosh