223 Remington (5.56x45mm)

Rifle: Bushmaster M4
Bullets: Midsouth, Grafs
Brass: Grafs

Hodgdon VARGET is the obvious best choice for 223, because it yields faster velocity, is a Hodgdon Extreme powder (which makes it relatively insensitive to temperature variations), and is a compressed charge in most loads.

Then again, perhaps I should look at some 223 "pistol" loads. My AR-15 has a 14.5" barrel, so I might get a good idea about how the performance of different powders changes with shorter barrel lengths.

Aside from the fact that I won't be getting my 204 Ruger for a while, one good reason for developing varmint ammunition for my AR-15 is that some day I want to get a night vision scope. I will be able to use it to hunt varmints at night. Using my Eraticator scope, I will figure out what works well in my rifle, and then it will be ready to use when I get my night vision scope.

55gr Varmint

This varmint ammunition will be used for larger varmints (like coyote). Now that I am thinking about doing some coyote hunting, this is more of a priority. I have nearly 500 of these BlitzKings, so I might as well use them.

Bullet55gr Sierra BlitzKing
Powder 25.5-27.5gr VARGET (compressed)
25.0-26.0gr H4895
24.0-25.6gr Benchmark
19.0-21.0gr H4198
21.0-23.0gr H322
PrimerCCI Small Rifle
CaseWinchester .223
COAL 
CrimpLight

I want to try all the Hodgdon Extreme powders available for this, which would be VARGET, H4895, BENCHMARK, H4198, and H322. That, unfortunately, is a lot of load development.


75 grain A-Max Experiment

I have heard that some 1:9 barrels are able to properly stabilize some 75 grain bullets. It's worth trying. I tested some Hornady 75gr HPBT ammunition, and they were stable at 100 yards. I have a box of Hornady A-Max bullets, which I should test. If they seem stable at 100 yards, I will have to try them at 400 yards. I might also try the Swift Scirocco bullets. The goal is to have something better for anti-personnel purposes than the 65 grain GameKing.

If those bullets don't stabilize, I should try the 70 gr. Barnes TSX. It will be expensive, but perhaps the best thing.


Personal Defense

Given that my AR-15 is really an anti-personnel weapon, and that I want to keep a stock of defense ammunition, it only makes sense that I develop something that is accurate in my gun. Keeping in mind that I have a 1 in 9" twist rate, I want a heavier bullet to give this load a little extra knock-down power. Ideally, I want to find a bullet that is constructed for hunting.

Hmm, Sierra has a 65 grain GameKing. It should be better than the Varminter, because it should have a tougher construction for more controlled expansion. It also has a boat tail, and of course it is slightly heavier. This may be my bullet.

Bullet65gr Sierra GameKing SBT
Powder Max 26.2gr VARGET
Max 25.6gr H4895
Max 23.9gr Benchmark
Max 24.6gr H335
Max 22.3gr H322
PrimerCCI Small Rifle
CaseWinchester
COAL 
CrimpLight

Hodgdon doesn't publish data for 65 grain bullets. Following is data that has been interpolated for 65 grain bullets using Hodgdon's data for 63 and 69 grain bullets. I should also check the Sierra book.

Powder63 gr.69 gr.65 gr.
VARGET26.4 (3199)26.0C (3010) 26.2 (3136)
H489525.5 (3078)26.0C (3069) 25.6 (3075)
Benchmark24.2 (3066)23.5 (2970) 23.9 (3034)
H33525.0 (3051)24.0 (2960) 24.6 (3020)
H32222.0 (2862)23.0 (2932) 22.3 (2885)

I really should do some velocity tests. Not counting the flash suppressor, my M4 only has a 14.5" long barrel. Slow burning powders produce impressive velocities, but they are tested in 24" barrels. Before I choose a powder, I really should learn which powders perform well in my shorter barrel.