The Flat mount ABR (Patented) will directly bolt on to the MPA BA, Hybrid, ESR and Bergara Premier Competition with an MPA Chassis models and it is supplied with the proper length bolts (short dowels). The two step aluminum cross stud for the monopod (called the Bag Rider Barrel) will be used and the ‘longer’ front mounting bolt - it will go up into the front slot of the ABR. The shorter bolt goes up into the rear slot. While ABR is opened start the two supplied bolts with your fingers - finish tightening with an Allen wrench. DO NOT take apart the ABR. There is a short 1/4-20 bolt installed in the ABR that has to be removed for applications other than the MPA chassis.

A new ‘Quick adjustment’ thread option (Coarse thread) is available for PRS, Hunting - use requires Hardened Dowels

The ‘Bag Selection’ page goes over the lower rider differences - ELR & V.The ABR has linear bearings that provides the ultimate in smoothness with zero wobble. The ABR provides about .95” of travel with the short dowel and 1.48” with the long dowel. Made in the USA from American 6061 Alum and finished with Class II Anodizing they are 12- 14oz.

Caliber restrictions for dowels:

.338 and smaller will use the Standard dowels
.33XC and larger will need the Hardened Dowels
PRS use requires Hardened Dowels

Direct Bolt On application:

MPA BA: Competition, Hybrid, ESR, Evolution, Lite, Ultra Lite, and Bergara Premier - Short Dowels (The Long dowels will require milling)

Modifications Required:

MPA BA: Competition, Hybrid, ESR, Evolution, Lite, Ultra Lite, and Bergara Premier-to fit the Longer dowels the rear dowel will have to pass into (not thru) the stock so milling a pocket is required (See pic with BLACK stock) or see the Installs page

ORYX Chassis -(Long Dowels) If your chassis does not have the slot for the M-Lok - we suggest to reduce height added to the rear stock- that you directly bolt onto the lower stock without adding a picatinny rail. Since machining to your stock is required either way to add the bolt holes (for a Rail or ABR direct mount) the Flat Mount ABR has two small slots and counter bored areas for the bolt heads to be recessed. See pic to left of ORYX chassis with Flat Mount ABR. If you do have a M-lok slot the Rail Mounted ABRis what you need.

XYLO chassis - (Short Dowels) The lower rider (part of the stock) will need to have 2 bolt holes added to mount the Flat Mount ABR (which already has 2 small counterbored slots).

Sig Cross- The rear stock must be modified to fit the ABR and the holes milled in the ABR to clear 10/24 bolts. Please contact us for details. The LOP plate must be modified to clear rear dowel. See pic and ‘Installs’ page

MPA Matrix - Custom installation (milling required) see picture and ‘Installs’ page

Tubb Rifles - (Long Dowels) please contact us

Daniel Defense Delta 5 Pro - See the “Installs” page

APAC Chassis - from JP Rifles - See the “Installs”page

Bergara BMP - See the “Installs” page

Please note that this product does not fit all MPA stocks. Will not work with “Modular Weight Tuning Kit”.

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