Quoted: I am interested in the difference between the standard m-4 style handguards and the 7.0 larue.  I know the weight of both.  I am curious when you take off all that is needed to take off the standard m-4 and replace it with the larue what is the real weight difference?  And with rail systems is heat an issue?

I would say that there is very little weight difference. Heat is not an issue with FF rails (esp. if your run a VG).


C4

www.gandrtactical.com

THE NEWEST LARUE 7.0 HAS A STAINLESS STEEL BARREL NUT THAT INCREASES THE FOREND TOTAL WEIGHT TO 11 OUNCES, I WOULD ESTIMATE. DIFFERENT CHOICES IN HANDGUARD PANELS WOULD ADD A BIT MORE.

I DO NOT HAVE A SET OF M-4 HANDGUARDS ON HAND TO WEIGH. TO THIS WEIGHT YOU NEED TO ADD THAT OF THE STOCK BARREL NUT, DELTA RING ASSEMBLY, AND HANDGUARD CAP, 2.7 OUNCES.

HEAT IS TRANSFERRED VIA CONDUCTION, CONVECTION, AND RADIATION. HEAT TRANSFER OFF OF THE CHAMBER OF THE WEAPON VIA CONDUCTION INTO AN ALLOY HANDGUARD MAY IN TIME CAUSE THE HANDGUARD TO GET WARM, EVEN HOT, BUT THIS IS A PREFERABLE SITUATION TO HAVING A HOT CHAMBER, IMO, WHICH CAN LEAD TO COOK-OFFS.

YOU CAN THINK OF A FREE FLOATING ALLOY HANDGUARD AS A POTENTIAL HEAT SINK, SOMETHING WITH BOTH POSITIVE AND NEGATIVE ATTRIBUTES.

AS COLDBLUE POINTED OUT ONCE, HIS WEAPON GETTING HOT WAS ONE MORE CLUE TO HOW INTENSE AND LONG A FIGHT HAD BEEN. THIS SENSORY INPUT COULD BE USEFUL TO A BRAIN HOUSING GROUP FOCUSED ON "OTHER THINGS" AT THE MOMENT.

HANDGUARD PANELS AND VERTICAL GRIPS DO REDUCE THE FELT HEAT, AS DO THE NOMEX FLIGHT GLOVES CERTAIN SHOOTERS SEEM TO WEAR.

STANDARD M-4 HANDGUARDS DO HAVE HEAT SHIELDS, IN THEORY TO PROTECT THE SUPPORT HAND FROM HEAT. BY DOING SO, THEY RETARD HEAT TRANSFER, SO THE BARREL AND CHAMBER NOT ONLY GET HOT; PLUS, THEY STAY HOT LONGER. EVENTUALLY, EVEN PLASTIC M-4 HANDGUARDS CAN GET QUITE HOT TO THE TOUCH. SEE REFERENCE TO NOMEX FLIGHT GLOVES, ABOVE.

THERE IS NO COMPARISON BETWEEN A STANDARD M-4 HANDGUARD AND CURRENT FREE FLOATING FORENDS LIKE THE LARUE 7.0 IN OTHER PRACTICAL MATTERS.

WES GRANT
M.S.T.N.

LARUE CHANGED TO A STAINLESS STEEL BARREL NUT BECAUSE THAT'S WHAT THEIR #1 CUSTOMER FOR THEM WANTED.

THE LARUE 7.0 WITH SS BARREL NUT WILL WEIGH 11 OUNCES. THE 12.0 WITH THE NEW SS BARREL NUT WILL WEIGH 16.6 OUNCES.

A COMPLETE M4 UPPER RECEIVER WITH FORWARD ASSIST AND EJECTION PORT COVER WEIGHS 9.0 OUNCES.

A RIFLE LENGTH MRP RECEIVER/FOREND MINUS BARREL WEIGHS 26.5 OUNCES. SO A LARUE 12.0 AND M4 UPPER RECEIVER WILL WEIGH ABOUT AN OUNCE LESS.

I DO NOT HAVE THE WEIGHT OF AN LMT CQB (SHORT) MRP RECEIVER/FOREND, BUT ONE MUST REMEMBER THAT IT ENDS UP A COUPLE OF INCHES LONGER THAN A RECEIVER WITH LARUE 7.0 FOREND, SO A COMPARISON WOULD NOT BE APPROPRIATE.

WES GRANT
M.S.T.N.