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s rtp,sTim Finleytheair,of.

and stillitan dby

the felt recoil from a PCP is the blast of air

mJsteryrommuZZIErakesuzzle brakes, air strippers,call them what you wil1,they've been arund fo ralmost 20 years and it'stime we understood morethem. Some shootersswearby them,think they're httle -o.L thaand most use them withoutunderstanding why. As a long-termhere's my take on the brake._ _A little history first. The Sportsmatchwas the first production airgun toany sort of muzzle, brake fiited asbought he l4thCZ off th e) - - ^ _ : ^ , , , i _ . _ , . *e= f : : . a_ l - : " , . . : : . : . , : i .

exiting behind the pellet pushing the riflebackwards. Howev. r-uil the -blast, the..'.,q"n',,s*!'j#w

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-#ri f leit can't be called to.taTlv**t was a revelation ln thei9B0s. Daystate soon followed suitdid Ripley and Air _Arms by fittingvented muzzle devices.There hssteadydevelopment of muzzle brakes.into what we now call a ,

pa in t 'splash' on, apainted target, bu t wil l have,

pellet and the *o."-r"il is Telt ,,

trouble seeine theshot fall . , l **

on a badly splattered or shot-up 'one. The more inefficient t evalvingsystemof th e PC p then themore ai r it wastes propell ing th e

tiny movement. What he mightnotice too is that he can't see ,,every pellet landing on th emetal target.They m y se e he",

when the pellet exits he barrel.This-is simply the 'for everyaction there's an equal and .opposite reaction' bi t ofNewton's laws of motion "'coming into eftect. Most of ''the energy eleasedby the expansionof thecompressedair wili end --, =

discerning shooter can feel the

up in the

Basicaily,he purpose of such devices sstrip off the turbulent air from aroundpellet as t leaves he barrel. The theorvit makes the peilet more stable iand therefore more accurate and alsothe unwanted air blast to nesateof the felt recoil of the rifle. A loi of

ffi ^terminal ballistics q: of the pellet nrrungth e target, bu t some isdirected into recoil, This,,.happens most noticeablv Iwith a plain muzzle, whrethe ar blast is directedforwards and therefore pushesthe barrel backr,tards n theopposite direction to thipel let's l ight.

*''o

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ft

brake acted as a front barrel support too, itbeing fixed to the reservoir.A variation onthe initial simple design is to fit moderatorstyle baffles between the vents, and thisworks very well.The very simple angled slot muzziebrake design was foliowed by Ripley Riflesuntil they began fitting a cone inside the veryfront of the brake body. The reasoningbehind the cone was to capture and directthe air blast quicker than the first simplebrakes with no cone present. fupley maestro,Steve Wilkins, machned a threaded hole inthe front of the brake into which the conecould be screwed. It also meant the conelength could be made speciftc to the pelletlength preferred by the owner and madecleaning with a puli-through quicker andeasier as the cone could be removed.Another benefit was owners could fit amoderator into the end of the brake with anextended tube from the mod' going back tothe crowning of the barrel to turn the rifleinto a properly silenced one.Airgun boffin, Pete Dutton, fits conesto all the muzzle brakes he makes and withmore barrels of PCP's overhanging the aircylinder now he cuts right-angled slots onthe top and bottom of the brake. I have one

of these on mv Air Aims MPR HFT rifle-Pete modified ihe large MPR muzzle braketo produce something very special. Thestandard actory brake is very long with no .cone system and has massiveslots on thetop surface.Pet'snew brake has amed thefelt recoil of the MPR to a significantamount. That to me is the main reason ofit a brake - to cut down the recoil.My Steyr LG-l10 FT rifle generatesnorecoil but I wanted an air stripper typebrake to enhance the u..ur".y^ at lngranges. So I went to Precision... where Iwas helped by Phil Hassle.Precision MadeCustom Bits IPCBJ and Phil Has_sles theman I went to. He uses a modified conewhich Walther and Steyr also use on theirpaper-punching pistols. The cone'sinternal diameter opens towards thetarget end. The cone has a larger internaldiameter at its exit than where the pelietenters it after leaving the barrel. Theadded bonus with the PCB air stripper isthe cone is adjustable for gap size, or thedistance rom the end of the barrel properto the start of the cone This is handy whenshooting different lengths of pellets; forexample a .777 calibre, 7.9 grain CrosmanPremier pel1et,whlch I use, s 5.6mm longan d the .177 8.4 grain JS B clone pellets s6.1mm 1ong.When I first fitted the PCBmodel to my FT LG- 110 I shot a 42mmthree shot group at 100 yards from aclassic FT sitting position. I think thisproves the air stripper stabilizes he pelletat long ranges.The PCB does not haveangled slots or baffles to act as an anti-recoil device, hat is not needed on Steyr's.

Phil has changed the shallow angle of thecone to a steeper one for use on otherrifles now, where the air blast stripped offdoes not travel mainly forwards as it doeson the early version he made for me.Now a word of caution;beware of somemuzzle brakes and air strippers made byso-called engineers and touted as the realdea1.Not all such devices are made to theexacting standardsfound in Pete and Phil'swork. Some of these 'garden shed types'have been known to open group sizes andincrease felt recoil rather than making therifle more accurate or cutting down onrecoil. Just don't go with the hype. Ask toshoot a rifle with an example of the brakeyou want first, then ask the owner of thatrifle if it really works and if it altered thepoint of impact when it was fitted. The realtest is to shoot it yourself, A.tymisalignment of the brake/stripper to the

The Stevr LG-100 and LG-l 10 PC Prifles have a moving, spring-loadedweightdirectlv behnd the bore of the barrel.Thiscounterweight is projected backwards asthe pellet is fired to counteract the feltrecoil. It works very well at 12 ft.lbs.but iseven better at its originally designedpowerof 6ft.1bs.,making paper punching versionsof the LGll0/100 total ly dead to shoot. Iown three Stevr rifles fitted with thedevice and I can always see where I hit, orindeed miss, which is very helpful onFT/HFT courses with a trckv wind.With very few rifles hving such ananti-recoil devce, let's look at th edevelopment of the muzzle brake intotoday's air strippers. As on the GC2 thefirst muzzle brakes were simple tubes withangled slots machined into the top surface.These were angled backwards towards theshooter to direct the blast of air in theopposite direction to the flight of thepellet. The vents were also machined onlyon the top of the brake as early PCPs hadthe pressurized air reservir below thebrake, with themuzzle flush tothe end of thereservoir. The

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Another thing to think about is thatmoderators are fitted with internal bafflesand act as air strippers too. The air iscaptured inside the body of the moderator,exiting some time after the pellet has leftthe mod', and they do have an effect on feltrecoil. My FAC rifle jumps like a good'unwithout the moderator fitted but acts ike adifferent gun when it is. I have a moderatoron my HFT LG-110 too, as I wanted totame the blast of the bare barrel and it iscalled Hunter FT after all. Another reasonto use a moderator for HFT is so you, andt-he shooter marshalling you can hear thepellet striking the metai face plate whereyou score a point.A lot is down to the actual rifle or pistolyou use as well aspersonal choice, whetherto go for a brake, an air stripper or amoderator. Ail my hunting rifles havemoderators and all my target rifles andpistols (apart from the HFT LG-l10) havebrakes or air strippers. A lot ofmanufacturers fit muzzle brakes ormoderators as standard now. I have a 1ot oftime for even the simplest of brakes, such asthe 'pepper pot' versions whlch are nowbeing used by the likes of Webley, FX andBSA. I have similar types fitted to myrimfire and fullbore rifles and, although thesimplest of the entire muzzle brake designsout there, they do work. Holes are drilled inlines around a cylindrical body, and there isno real need to index the holes to line upvertically if they are spaced close enough, so

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