KAC Knights Armament M5 RAS Quad Rail Set

(2 customer reviews)

This product is currently out of stock and unavailable.

  • Knights Armament Company (KAC)
  • P/N:98065
  • Upper Rifle Rails (quadrails), M5 RAS
  • Black
  • 11.5″ Rail Set, Top and Bottom Rails
  • Non free floating rail
  • Drop in replacement for two piece A-2 type handguards
  • For rifle length gas systems
  • Delta ring assembly, Fixed front sight/gas block, and Round or Triangular type handguard end cap needed for fitment
  • Government profile barrel contour for best fit
  • Heavier barrel contours may require modification to the inside of handguard
  • Genuine Army Surplus, Military Surplus

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This quality M5 Quad Rail Adapter System (RAS) is manufactured by none other than Knights Armament. Easy installation for the top and bottom rails. The KAC M5 RAS rail system was used by the US Military in the M16A4 rifle. Proven in the field this rail system is great for the AR-15 enthusiast and for building correct civilian M16A4 rifle clones. Rifle requirements for correct fitment include: Compatible with two piece A-2 type handguard, rifle length gas system, delta ring assembly, fixed front sight post/gas block, and either a round or triangular handguard end cap. Secures to rifle barrel nut with a clamp and screw arrangement for very secure fit on rifle.

This set of M5 RAS comes in both new and pre-owned conditions. Pre-owned means these rails are in good condition, they have some obvious wear and are a little bit dirty but guaranteed to be fully functional. See the pictures for an accurate visual representation.

This quad rail can be purchased as the rail alone or with a set of rail covers.

Rail Cover Set Includes:

  • 1 x Upper Quad Rail
  • 1 x Lower Quad Rail
  • 3 x 11 Rib Rail covers
  • 2 x 9 Rib Rail covers
  • 2 x 5 Rib Rail covers
  • 1 x 6 Rib Rail cover
  • 1 x KAC vertical grip
  • National Stock Number (NSN): 1005-01-562-9480
  • Part Number: 25442+5
  • Noun: Retainer, Gun Compon

Additional information

Weight27.6 oz



Quad Rail Only, Quad Rail & Rail Covers

2 reviews for KAC Knights Armament M5 RAS Quad Rail Set

  1. Erik (verified owner)

    Ordered this for my first AR and It arrived in really great shape and really fast too. It is a little on the heavier side but if you don’t mind and are looking for genuine surplus or to add this to an A4 clone then this is for you.

  2. sean (verified owner)

    Excellent rail for your M16A4 clone setup, came well packaged and with incredible speed, I am impressed! Will recommend to others and I will be back as a happy customer.

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US Military clothing in general runs in BDU sizing. If you are unsure about your proper size for clothing this chart will help you find your general size across all clothing, unless otherwise noted in the description.

XSR29-3267-7124 1/4
SS33-3663-6723 3/4
SR33-3667-7124 3/4
SL33-3671-7525 3/4
MS37-4063-6724 1/4
MR37-4067-7125 1/4
ML37-4071-7526 1/4
LS41-4463-6724 3/4
LR41-4467-7125 3/4
LL41-4471-7526 3/4
XLR45-4867-7126 1/4
XLL45-4871-7527 1/4
XXLR49-5267-7126 3/4
XXLL49-5271-7527 3/4
3XLR53-5667-7127 1/4
3XLL53-5671-7528 1/4
4XLR57-6067-7127 3/4

XSR23-2729 1/2 - 32 1/2
SS27-3126 1/2 - 29 1/2
SR27-3129 1/2 - 32 1/2
SL27-3132 1/2 - 35 1/2
MS31-3526 1/2 - 29 1/2
MR31-3529 1/2 - 32 1/2
ML31-3532 1/2 - 35 1/2
LS35-3926 1/2 - 29 1/2
LR35-3929 1/2 - 32 1/2
LL35-3932 1/2 - 35 1/2
XLR39-4329 1/2 - 32 1/2
XLL39-4332 1/2 - 35 1/2
XXLR43-4729 1/2 - 32 1/2
XXLL43-4732 1/2 - 35 1/2
3XLR47-5129 1/2 - 32 1/2
3XLL47-5132 1/2 - 35 1/2
4XLR51-5529 1/2 - 32 1/2

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