Hot handguard solutions

[Ol` Joe]

That’s what I was kind of thinking, but didn’t know what kind of negatives to expect. This thing already takes a couple moons to cool off before I feel ol stuffing it back into its case. I don’t want to accidentally kill the barrel.

Pressure and hot gas flow erodes throats, not that an already hot barrel doesn’t compound the issue. If you’ve shot to the point you can’t comfortably hold the barrel in your hand and continue shooting, the barrel is suffering damage. Letting it stay in a warm/semi hot state during use is likely to cause the least damage. Mag dumps? A few quick 30rd mag changes without cooling is going to do noticeable damage. Need an oven mitt to hold on to the tube or it’s so hot you are afraid to case it and it on its way to becoming toast.

Note that the damage may not be all that apparent if you are not keeping track of accuracy from the start. If all you expect or desire from your rifle is the capability of hitting a 12” gong @100 yds you most likely won’t see much change Until the bullets start flying sideway. I changed out a barrel on a M70 HV .223 a few years back that had at least 8/9K rds down it and, had been boiling hot more then once. The throat was a checkerboard for the first 5” or more, but it would still hold 5 rounds around 1.25” or a bit less at 100 yds, but when new and for most of the time I shot it, it was a honest .5” rifle. The new barrel has it back shooting the little bug holes I expect from this type of rifle.

[10x25mm]

That’s what I was kind of thinking, but didn’t know what kind of negatives to expect. This thing already takes a couple moons to cool off before I feel ol stuffing it back into its case. I don’t want to accidentally kill the barrel.

The mineral wool tape found by dirtmcgirt76239 is much better than fiberglass and a good find for your application. Mineral wool battings are rated at a minimum of 1,200°F. Mineral wools usually cost 50 to 100 times the cost of fiberglass. They only get rated at that low temperature due to the binders, not the mineral fibers. The mineral wool fibers themselves don't melt or soften until you reach 1,800°F. Binders are also the weak link for most fiberglass batting.

Early in the M16 program, the Army encountered pencil barrel distortion and handguard charring after rapid firing strings of 120 rounds or more. The belt fed AR-10s were abandoned after steel barrels split and/or warped around 100 rounds of continuous fire. The belt fed AR-10s had fiberglass insulation installed inside their FRP handguards early in the program after several of their handguards caught fire during testing. This gives you some round count data points to consider should you insulate inside your handguards.

[Fuel Fire Desire]

The muzzle device stays comparatively cool to the rest of the assembly. It’s also aluminum.


The way I typically shoot this, is a mag of 30 at about 1rnd/sec, a 60 second wait while I get a new mag, then another 30 rounds at the same rate. By the end of those it’s cooked.

If I do do a mag dump with it, it’s usually by doing Mozambique triple taps with a 1-2 second gap in between. Just one of those and it gets pretty toasty.

Once it’s warm, I change to a different gun to let it cool. I’ve never done a string of 100 through it consecutively because of the heat.


This is as fast as I go. In fact, this is a very rapid cadence for me. About one mag of this and it gets put away for 15 minutes.


https://youtu.be/5VN4iA9iJQQ