AR-15 Handloads (How To Prevent Jams)
This is what a typical "fail to feed" jam looks like when using light loads.
The AR-15 is a super reliable rifle, and they can be made to deliver outstanding long range accuracy.
I’ve spent years working on these rifles, and there are jillions of aftermarket parts available for them. However, I've seen a lot of these rifles jam
(just like any other semi-auto) with a wide variety of ammunition.
Lightweight bullets have such light recoil, you can always see the bullet impact.
We needed thousands of rounds for this trip, and since we were in a pinch for time, we decided to use affordable factory loads made by Fiocchi.
Our previous testing proved that this ammo delivers consistent MOA accuracy (or better) in all of our rifles. At 3,620 fps, these are HOT, flat shooting loads.
However, as hot as these loads are, they didn’t always operate the AR-15 action. To avoid intermittant "fail to feed" jams, I had to use my AR-15 in single shot mode.
My last prairie dog hunt involved two of us using AR-15 rifles with 40 grain bullets. We used them mainly to reduce barrel jump and allow us
to see the bullet impact. It is a rewarding sight to see a prairie dog get blasted. Sometimes they fly 10 feet in the air while spinning like a propeller.
Sometimes they explode like a clay bird, and sometimes they just disappear with a familiar sound . . . . Whack!
"Fail to feed" symptoms are very common, because most semi-auto actions rely on your ammo to operate the action. This means that your ammo
needs to produce enough pressure to fully operate the action. I’ve also found that you can even shoot steaming hot maximum loads (with lightweight bullets) that fail to
raise pressure quickly enough (and last long enough) to always drive the bolt carrier fully to the rear. When bolt travel is limited, it causes intermittent “fail to
feed” symptoms. This is called “short stroking”.
It’s easy to test your rifle for "short stroking” by simply firing one round with an empty magazine inserted. If the bolt doesn’t always
lock to the rear, you can bet that your loads will cause an intermittent “fail to feed” symptom. When testing lightweight loads, you may need to fire a hundred rounds this
way to be sure you have 100% reliability. Most shooters just see a "fail to feed" symptom, and they never know what actually causes it.
“Failure to feed” symptoms can also be caused by incompatible parts, but those situations are fairly rare. There are things you can do to "tune"
an AR-15 to operate with lightweight loads. I’ve tried using lightweight bolt carriers, lightweight spring buffers, different muzzle brakes, carefully fitted gas tubes, and
lightened recoil springs. You’ll need a lot of ammo (and a lot of time) to verify complete reliability. However, using the correct (tested) ammo is by far the most
important factor to ensure a reliable functioning AR-15.
Extra weight on the forearm will reduce barrel jump, and now I can use heavier bullets.
Next year, I'll use my standard AR-15 load that uses the 69 gr SMK bullet. I've also added seven extra pounds to the forearm of my rifle.
I cut (3) steel tubes, filled them with lead, and bolted them on three sides of the quad rail with scope rings. This rig works great when you're shooting from a
bench. It now allows me to see the bullet impact even with heavier bullets. The heavier bullets will operate the action perfectly. I’ll can now use heavier
bullets that can reach out to 600 yards. After verifying my new trajectory chart, I'll be ready for my next prairie dog hunt.