Heavy Weight Chassis Supremacy


Avid readers will know that we have reviewed and viewed rifle chassis’s from Modular Driven Technologies before.

This time we are going to look at the latest full chassis platform from MDT, the ACC which is pretty much a purpose built platform for competition rifle shooters. A ground up redesign from prior MDT platforms that took all the good elements and added the features customers were shouting out for, pretty much every thing you can think of is possible with this chassis.

MDT didn’t hold back on the ACC, everything about the chassis seems to be pretty much perfect.

Pictured here with the Howa 223 in the older MDT HS3 light weight chassis.


The Cerakote is outstanding, the machining is as good as it gets with smooth curves and ruler edge straight lines, anything that can benefit from being adjustable is.. adjustable. The cheek rest and adjustable buttstock are very easy to adjust using thumb screws and lock in place with zero movement, no tools needed, but everything locks in tight and firm.


MDT also introduced a new adjustable vertical grip with the ACC allowing you to move it further away or closer to the trigger to achieve the best positioning possible. Big hands or small hands will be able to set this chassis up to match your ideal grip. The chassis has a built in thumb ledge above the grip which lends perfectly to laying the thumb on the palm side of the rifle. The chassis is compatible with any AR15 style pistol grip which means you can run any ergonomic grip style you like.

The vertical adjustable grip is not the only revolutionary feature of the ACC, MDT also included the ability to tack on weights to allow you to balance the rifle anyway you want. Weights can be added to the sides of the forend, in the buttstock. Not only can the weight be added quick an easy to the outside of the forend, there is special slots milled inside the forend to allow the semi permanent insert of custom weights. This gives you total control over the total weight of the system but also where that weight is located to suit your style of shooting like no other factory chassis system before.


A heavy rifle helps in reducing felt recoil, adding weights in the right place makes the rifle steady and to be able to balance the rifle on barricades or ledges to aid in supporting the rifle for increased stability. As you can see in comparison to the HS3 pictured above, the forend is very long, this is absolutely superb to allow for the bipod support system to be mounted as far forward as possible to aid in gaining the most stability possible. Mounting to the front picatinny rail is my Boscabel Beloc Bipod.


Adding weight to a rifle isn’t new to custom rifles– what is different is the ability to place the weight exactly where you need it and also the fact that it is a factory made chassis with out the custom shop price tag.

The weights are fixed using the Magpul M-Lok system so they are not really designed to be changed in the field, mostly pre set to how you want it.

The full length of the underside of the forend is both M-Lok compatible but also housed built machined ARCA Swiss rail, which is the latest and greatest bipod and tripod mounting system, carried over from high end heavy weight camera tripod mounts which offers the most secure mounting system on the market. The ACC was the first chassis with the ARCA rail built in.

Installing the Remington 700 short action into the chassis was as simple as any other chassis, the two action screws were perfectly aligned and perfect length. Torqueing the action down into the chassis positioned the barrel dead centre into the chassis. Even 46cm forward of the bedding the barrel in perfectly in the middle which proves not only that the barrel is straight but also the machining on the chassis is primo!

At the back end of the rifle, the chassis comes with the MDT Skeletonized fixed and highly adjustable stock. The cheek piece can be raised massively to suit any scope height and neck position, the check piece can also be moved side to side to allow the head to move further over the stock to align with the eye piece of the scope to ensure absolute comfort behind the glass. The adjustments don’t stop there, the length is also adjustable at the rear pad to allow for a longer or shorter length of pull which is ideal for bigger bodies and also different clothing. Above is the main features you see, there is also a whole long list of specialities under the stock is a line of M-Lok slots, which is to allow for bag rider attachments and rear supports, In front of the AICS pattern mag well is a barricade support wedge to aid in firmly pushing the rifle into shooting supports. The rear of the chassis can accept folding stock adaptors and also other MDT ESS style butsttocks to allow for customisation if you wish.


Shooting the 300WSM in the ACC had completely changed the rifle. For years the custom action has been in my much loved GRS laminated stock (older setup pictured below with my home made forend extension), which I do absolutely love but it does fall short on a few

key areas that the ACC comes on strong. That is weight and length. The Shorter GRS stock doesn’t have much front end real estate and is too short to allow a bipod to be mounted for enough forward to stabilise the barrel in recoil. The ACC is almost twice as long out front which is most definitely allows for a forward bipod for absolutely superb chassis control.


The ACC is with our a doubt one of the premier rifle chassis on the market a the moment and it doesn’t carry a big price tag in comparison to a few opposition products on the scene. Chassis from KRG are not much dearer but definitely more than the ACC, but when comparing to MPA and other higher priced systems from the Likes of JAE and Cadex you really start to realise how good a value the MDT is. That’s not saying I wouldn’t want a chassis from all these brands, they are all no doubt outstanding.


My trusty Leupold Mk4 6-20 FFP scope is also mounted up using MDT 6 bolt Heavy duty rings to match the chassis with the Vortex bubble level up front. Thanks to Covid range restrictions I haven’t yet had the chance to shoot the with the chassis but I hope to in the coming weeks. The 300WSM cartridge was quite brutal to shoot from the GRS Laminated stock, Im expecting the round to be substantially softer shooting now seated in the chassis weighing twice the amount of the stock.

Il keep you posted once Its been to the range to make expensive noise!!!

Back to blog