Hello folks.

I have a SIR for my carbine, and I know it works great for heat dissipation. I made that decision after shooting a couple hundred rounds under summer sunlight.

Now I have a 20" rifle and I'm wondering if this rifle too is sensitive to heat as carbines do. When I mean sensitive to heat, I'm saying whether it can hold itself under sustained fire without significant damage. No I don't do mag dumps often (three times using 20 round mag during last two years and I'm not doing it whatsoever again).

I'm trying to decide if I will benefit from KAC M5 RAS or not. I'm not really interested in attaching any stuff, I just want mil-spec foreend that dissipates heat very quickly. I would normally have saved up $$$ and just went ahead to buy it, but my rifle is heavier than my carbine and I wanted to see if I can get same cooling benefit at the cost of more weight. Thanks for reading.

A 20" barrel will take longer to heat up and will cool down faster than a carbine because it has both more mass and a greater surface area.

Whether that is fast enough for you, I can't say; but it should handle a back-to-back 7 magazine dump.

Two options:

1. Shoot with NO HANDGUARDS, or

2. Get the Super soaker attachment modular Socom Tactical Barrel cooling System!

[ROFL]

Seriously, I never fire any faster than the U.S Army recommended sustained rate of fire. However I did that under direct sunlight and my carbine went really HOT. I guess I will try that with my rifle next summer and see how it does.

My problem with standard rifle handguards is that it doesn't have holes in rear portion of it, so me being simplistic joe thought it would block the air flow.

Yes.  We have the same prob out here in AZ.  Believe me!

I just take breaks on the AR and plink .22 rimfire while the rifle cools a bit IN THE SHADE!  

pee on your barrel if it gets too hot.

Folks around here worry WAY too much about barrel heat!

NEWS FLASH:......Barrels get HOT when lead passes through them! LOL

They get hotter when you ignite deflagrating mixtures in them.