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‘No Gunsmithing’ muzzlebrake models

Megamax-2ST (self-timing) muzzle brake

Megamax®-2ST (self-timing) side-port muzzle brake for sporting and tactical rifles. (New for 2024 !)

  • Scaled-down revision of original Megamax Ø1 ¼” /32mm muzzle brake, but with no upward bias in the gas porting, for a true bi-directional indexing design.
  • Minimised ground dust disturbance
  • Only adds approx. 2″ /50mm to barrel length (Brake overall length – minimum 2.550”/64.7mm)
  • Weight: approx. 125 grams (depending on clearance hole diameter)
  • Diameter ⌀990″ (Ø25.15mm)
  • Thread sizes: ½-20 UNF, ½-28 UNEF, M14x1.0mm, 9/16-24 UNEF, M15x1.0mm, 5/8-24 UNEF, M17x1.0mm, M18x1.0mm.
  • Specifically designed for all calibres from .224cal to .30cal. max.
  • Design registration number: NZ433600
  • No gunsmithing required (if ordered with correct calibre clearance hole)
  • Measured recoil reductions of up to 75%*.

 

ABOUT MEGAMAX-2

  • Megamax-2 meets the requests from our local and international customers for a scaled-down version of our original Megamax® muzzle brake (patented since 2013), but with zero gas-bias, and also a special (tool-less) self-timing model is offered as well.
  • Designed for use on barrels from Ø15mm to Ø25mm muzzle diameter, where an effective side-port style muzzle brake is required. Featuring our proprietary graduated aperture design, perfected after numerous prototypes to provide the maximum possible recoil reduction in a 4-chamber muzzle brake with 10-degree rearward draft. For it’s size the Megamax-2 provides outstanding recoil reduction and muzzle control with no downward bias – essentially a bi-directional indexing brake.
  • Side-port type brakes tend to create less ground dust disturbance than radial type brakes when shooting prone over dry dusty ground.
  • Made from 300 series stainless steel.
  • Dual index marks are machined on the body of the brake to aid the installing gunsmith or shooter to align the brake correctly onto the barrel. (On ‘gunsmith model’ brakes the installing gunsmith must also bore the clearance hole to be at least ⌀0.030″ over bullet diameter.)
  • Megamax-2ST (self-timing) model – brake can be indexed with or without tools. Indexing can be pre-set for a specific rifle in conjunction with the use of internally-fitted indexing shim-washers, which means that the brake can be regularly removed or refitted hand-tight with no need to manually re-index (or ‘time’) the brake each time it is refitted to the barrel.
  • Simple adjustment design maintains good bore alignment, and won’t become seized or clogged with powder fouling or corrosion – unlike some popular brakes that use a tapered-cone mechanism for self-indexing and locking into place.
  • Thread recess depth on this model is approx. 0.600” deep, but will self-adjust (via the knurled indexing nut) to accommodate slightly longer threads
  • (* Results are indicative from testing on our purpose-built apparatus with factory-loaded ammunition: 7mm Rem Mag 139gr Hornady factory ammo – 74.85% recoil energy reduction. Measured results will vary with different ammunition selections.)

European rifles – Blaser , Sauer , Mauser , Merkel , Sako , Tikka , Bergara .

These rifles are very popular in New Zealand and Australia, and increasing in popularity in the USA
and Canada. We can supply some of our muzzle brake models to be a ‘no gunsmithing’ fit onto a lot
of these rifles that have factory-threaded barrels. (Note however that we cannot guarantee correct
fit onto barrels that have already been ‘gunsmith-threaded’ due to circumstances beyond our
control, as the gunsmith threading can vary slightly (or a lot) depending on who did the machining
work on the barrel.)
Before ordering from us PLEASE CONFIRM THE EXACT THREAD SPECS AS MEASURED ON YOUR
BARREL – DO NOT RELY ON ON-LINE SEARCHES TO DETERMINE YOUR BARREL SPECS AS THIS MAY
VARY DEPENDING ON YOUR LOCATION, OR INDIVIDUAL RIFLE MODEL. This has become a problem
here in NZ with brands like Bergara or Sako/Tikka, where our local importers bring in rifles from the
European market with muzzle threads like M14x1.0mm or M15x1.0mm – and the latter here is often
mistaken for the 5/8-24 thread which is listed on the Bergara USA website (where for example ½”-
28 and 5/8”-24 are the industry standards). But to confuse things some models of Sako/Tikka and
Bergara DO actually present in the market here with 5/8”-24 threads, so PLEASE PLEASE measure
your barrel with dial calipers or digital calipers before emailing us with your order request.
We need to know: Muzzle thread diameter (and thread pitch), exact thread length from muzzle face
to thread shoulder face, and the barrel diameter behind the thread section.
BLASER RIFLES (and modern rifles with barrels produced by the ‘Blaser Group’, such as Sauer,
Mauser (M18, M12, etc), Sauer, Merkel: (These rifles usually have a nominal 15mm thread length)
Quatromax muzzle brake (standard Ø22mm) – pre-tapered at rear and pre-bored for calibre
clearance. Supplied in either polished or bead-blasted stainless steel finish. Black coating option (at
additional cost) is available.
Thread sizes: M14x1.0mm x 0.600” (15.24mm) long , taper for Ø17mm barrel.
M15x1.0mm x 0.600” (15.24mm) long , taper for Ø17mm or Ø19mm barrel.
M17x1.0mm x 0.600” (15.24mm) long , taper for Ø19mm or Ø20mm barrel.
M18x1.0mm x 0.636” (16.15mm) long , for 22mm barrel (no taper, unless Ø24mm
Quatromax brake is supplied instead of standard Ø22mm brake.)
Megamax-2ST: Standard Ø0.990” (Ø25.15mm) self-timing side-port style muzzle brake. Available in
all of the above thread sizes, with option of black coating if requested (at additional cost). Note that
there is a standard rear end-nut on this model at a fixed diameter, so it does not have a conventional
rear taper like the Quatromax or standard Megamax or Megamax-2.

SAKO & TIKKA RIFLES
All thread size and diameter options as above. Bead-blasted stainless standard finish, or black
coating option (at additional cost) is available. (These rifles usually have a nominal 15mm thread
length length)

Note that some models do have 5/8-24 muzzle threading, but the thread extension length is usually
still about 15mm long. Please confirm exact specs on your rifle before your order/enquiry.

BERGARA RIFLES
Note that these rifles usually have a longer nominal 16mm long thread extension.
Quatromax muzzle brake (standard Ø22mm) – pre-tapered at rear and pre-bored for calibre
clearance. Supplied in either polished or bead-blasted stainless steel finish. Black coating option (at
additional cost) is available.
Thread sizes: M14x1.0mm x 0.636” (16.15mm) long , taper for Ø17mm barrel.
M15x1.0mm x 0.636” (16.15mm) long , taper for Ø17mm or Ø19mm barrel.
M18x1.0mm x 0.636” (16.15mm) long , for 22mm barrel (no taper, unless Ø24mm
Quatromax brake is supplied instead of standard Ø22mm brake.)
Megamax-2ST: Standard Ø0.990” (Ø25.15mm) self-timing side-port style muzzle brake. Available in
all of the above thread sizes, with option of black coating if requested (at additional cost). Note that
there is a standard rear end-nut on this model at a fixed diameter, so it does not have a conventional
rear taper like the Quatromax or standard Megamax or Megamax-2.

Quatromax® – Blaser R93 & R8 special models

Quatromax® – Blaser special model to suit diameter 17mm factory threaded barrel (M15x1.0mm). Also now available is a special model for the Blaser ‘semi-weight’ barrel (20mm diameter) threaded M15x1.0mm. (M17x1.0mm thread option – now available) Note that Blaser ‘Semi-weight’ barrels can now be either 19mm or 20mm diameter – please specify exactly which one you have when ordering.

Available in M15x1.0mm standard thread or M15x1.0mm ‘tight-spec’ thread (to suit factory-threaded Blaser barrels).

(NOTE: ‘Tight spec’ thread version is only intended for barrels with the factory muzzle thread done by Blaser factory, as they seem to undercut their muzzle thread by 0.006″ to 0.007″. To compensate for this our ‘tight spec’ thread is 0.005″ undersize on crest cut diameter, so the fit of the brake will be fairly close and not too sloppy on the thread fit.  If your barrel has been threaded by a gunsmith then please specify the ‘standard’ M15x1.0mm thread.)

Supplied pre-tapered and bored for calibre clearance; please specify calibre when ordering. Black coating of these stainless steel muzzle brakes is available if required for a small additional cost. (See price list for details.)

Also available is Quatromax M18x1.0mm thread to suit Blaser ∅22mm barrel, and also a M17x1.0mm thread for Blaser ∅19mm or ∅20mm barrel (please specify when ordering by email).  Note that the ’22mm’ brake is actually 22.2mm diameter, and is also able to be fitted to Sako or Tikka 22mm diameter barrels with M18x1.0mm thread.

 

For the UK market we are also now producing a special adaptor sleeve and Quatromax brake combination (ordered together) for use on the Blaser factory threaded ‘spigot’ type barrel. Note that these barrels use the ‘standard’ spec M15x1.0mm threaded muzzle brake, NOT the ‘tight spec’ option. Black coating option available. Please email us for more details.


Quatromax® -AR15/AR10 special model

Quatromax® – AR15/AR10 special model. 

(This pre-tapered model is also suitable for the Ruger Predator and Precision Rifle, and any others with 0.750″ diameter barrel and milspec ½-28 or 5/8-24 threading.)

Available in ½-28UNEF or 5/8-24UNF standard spec thread, 0.636″ long thread recess.

Can be supplied either untapered at rear, or pre-tapered and bored for calibre clearance; please specify calibre when ordering.

Black coating of these stainless steel muzzle brakes is available if required for a small additional cost. (See price list for details.)


Megamax® Quicktime™ Kit

This system has been primarily designed for factory threaded barrels which have a thread extension length between 16-17mm, or milspec-threaded nominal 5/8″ thread lengths. Current thread sizes and (Internal diameter) barrel clearance sizes available as follows:

½-28: ∅0.760″ (Std AR15), ∅0.893″ (ideal for JP ∅7/8″ AR barrels)

5/8-24: ∅0.760″ (Std AR15 or AR10), ∅0.806″ (for Tikka T3 CTR), ∅0.860″ (for Remington & Savage heavy barrels), ∅0.935″ (for DPMS & similar heavy ∅0.920″ barrels)

M14x1.0mm: ∅ 0.688″
M15x1.0mm: ∅ 0.688″
M18x1.0mm: ∅ 0.888″

*Note: The thread ideally should be of a length from 16-17mm long, with NO generous thread relief undercut just before the thread shoulder. (i.e. as found on some Sako or Blaser barrels). Most US-Milspec threaded ½-28 and 5/8-24 barrels that feature a thread cut that runs up very close to the shoulder are ideally suited to this brake/lock nut system. For barrels that do have the deep thread relief a rubber O-ring can be installed to prevent the Rapidex™ nut running partially or fully off the threaded section – which could possibly cause thread damage if the Rapidex™ nut was over-tightened with only partial thread engagement.

Another unique feature of this system is that it does not actually require a thread shoulder on the barrel at all – this is because the brake is secured tightly due to tension/friction between the brake body and the special Rapidex™ locking nut.  What this means is that accuracy-minded gunsmiths can fit this system to custom barrels and use the largest thread size possible for a given barrel diameter/size at the muzzle in order to avoid the chances of bore enlargement due to excessive metal removal and resultant stress release which can occur in some barrel types. Example: If you have a barrel with a muzzle diameter of ∅0.710″ you could effectively use an M18x1.0mm thread (∅0.708″) cut about 16-17mm long with no shoulder at all and install the Megamax Quicktime™ system.
Another advantage of the Quicktime™ system is that the brake can be quickly removed and swapped between different rifles which have same thread and similar barrel diameters. Additional wrenches or Rapidex™ locking nuts may be purchased separately if required.

The kit features a Megamax® muzzle brake of the requested thread size and pre-bored to specific calibre clearance, a special Rapidex™ tapered locking-nut of a specific barrel clearance diameter, and a specially-designed wrench to fit the Rapidex™ locking-nut. A small length of plastic rod is also supplied which is inserted through the brake ports when tightening the nut/brake onto the rifle at the correct index/alignment point.

See our video below to check out just how fast and easy this system really is. Can be supplied in either stainless polished finish, beadblasted finish, or black-coated bake-on paint finish (GunKote – Flat Black or Satin black. Note that there may be an additional charge for coating of some models or custom-orders.) Registered Design (Design Patent): NZ421243 . International Patents Pending.


Tresamax® and Varimax®-QC sleeve & shim indexing kits

This system has been primarily designed for factory threaded barrels which have a thread extension length between 15-17mm, or milspec-threaded nominal 5/8″ thread lengths. Current thread sizes and (internal diameter) barrel clearance sizes available as follows:

½-28: ∅0.752″ (Std AR15)

5/8-24: ∅0.752″ (Std AR15 or AR10), ∅0.792″ (for Tikka T3 CTR)

(Tapered sleeves to suit the Blaser M15x1.0mm and other sport-weight barrels are on custom order only at this stage.)

For this system it doesn’t matter if there is a thread relief under-cut before the shoulder or not, as there is no female thread in the sleeve itself on this model – the sleeve just fits loosely over the barrel and must be approximately aligned with the brake body before snugging it up tight.
Shim washer kits (featuring multi-thickness ∅0.750″ outer-diameter shims) for either ∅½” or ∅5/8″ threads can be supplied by us, or you can purchase them directly from Brownells (USA), or elsewhere.  Using a shim-washer (or multiple washers) of varying thickness the customer can set the brake to pull up tight with a plastic dowel rod to stop just short of the correct radial indexing point.

The brake is supplied as bored for a specific calibre clearance, and can be coated black as an optional extra if required. Please specify your exact barrel diameter and calibre when ordering, and whether or not you wish to purchase a shim kit from us as well. Making your own special shim washer on a lathe is also another option, and this fits up inside the tapered sleeve so it is hidden from view.
This is similar in some ways to the Megamax Sako/Tikka special model, which also has a hidden recess for housing an indexing shim washer.

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