77gr .223/5.56 load recommendations?

[GyroF-16]

I’m interested in starting to reload .223/5.56

I’ve got plenty of 55 gr factory ammo on hand, so I’m eyeing 77 gr for longer(-ish) range precision since decent 69-77 gr ammo is still pretty expensive. I figure I can reload for 60% of the commercial cost or less.

Right now I have a pound of Varget on hand, and 100 77gr Sierra Match King projectiles.
I’m interested in both cost-effectiveness and accuracy as I go forward. A projectile with good terminal effects would be an added bonus.
Longer, heavier projectiles from 69-77 (maybe heavier?) are my focus.

In my current level of ignorance, I’m considering buying more 77 gr SMK in bulk and either Varget or CFE 223 (CFE 223 seems to be about $40/lb around here, while Varget is over $50/lb).

But I don’t know what I don’t know.

Input is welcome.

[SecondsCount]

You can't go wrong with a 77 SMK. Load them at 2.260 OAL, and they shoot very well.

Varget is the most popular powder for 69+ grain 223 loads. It can be pricey, and sometimes hard to find. CFE223 meters well and a good friend likes it for his 77 grain loads. It is a ball powder so it is going to be more sensitive to temperature extremes, which is an issue if you are loading near max or worried about velocity variances at longer distances.

$40-50 lb powder is highway robbery but I guess that is where we are these days. I've seen TAC become available for ~$25 lb in 8 pound jugs lately and it performs well behind heavy bullets.

Reloder 15 and VihtaVuori N140 are good alternatives to Varget. Lately I have been shooting N540 in my bolt action. On my last test, 24.5 grains with a 77 yielded a 0.41" 5-shot group. I want to try and see if I can get another 0.5 grains because I think it will burn a little cleaner there, and clean up the deviation in velocity.

[mmc45414]

Right now I have a pound of Varget on hand, and 100 77gr Sierra Match King projectiles.
I’m interested in both cost-effectiveness and accuracy as I go forward. A projectile with good terminal effects would be an added bonus.
Longer, heavier projectiles from 69-77 (maybe heavier?) are my focus.

You can't go wrong with a 77 SMK. Load them at 2.260 OAL, and they shoot very well.

Varget is the most popular powder for 69+ grain 223 loads. It can be pricey, and sometimes hard to find. CFE223 meters well and a good friend likes it for his 77 grain loads.

I think a big question is how you plan to meter the charges, and if you are planning to do single stage or progressive. Are these for a bolt gun or carbine? I figure Imma gonna drop charges for a carbine, and I do not currently have a bolt gun in .223. So I am going to drop charges, and if I am doing this on a progressive, I want to use the powder check. So I want to use some kind of ball powder since I will just meter the charges and load the rounds on a 650, so I also use the powder check. But I am just loading general use rounds, and use some at three gun.

The way I figure it is that you can load 77gn for the same effort.

If you are going to weigh each charge I say get started with the Varget, but if you meter it there can be bridging and other inconsistency, so I would for sure use a powder check if you are on a progressive.

I bought a bunch of SMK77s one day when I found them in stock, and I have a bunch loaded into nice once fired LC cases. Now I am curious about these RMR 75gn BTHPs (ETA: I forgot the link...), since they are like half price. I will probably get some and load them into random cases I bought, when you miss at three gun you just shoot again, and it not typically because of the cartridge...

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...

I bought a bunch of SMK77s one day when I found them in stock, and I have a bunch loaded into nice once fired LC cases. Now I am curious about these RMR 75gn BTHPs (ETA: I forgot the link...), since they are like half price. I will probably get some and load them into random cases I bought, when you miss at three gun you just shoot again, and it not typically because of the cartridge...

I have been running the 69 3GH with a glimpse of success. Some five shot, 100 yard groups as small as .25" and then they fall apart, spreading out to as large as 2". Powder on the slower side works best for my tests.

It will be interesting to see how the 75 performs for you.

[GyroF-16]

I’ll be loading on a Lee Classic Turret press, using either a Lee double disk powder measure or the Lee Auto Drum (I have both).
I generally weigh 10 or more drops for a given setting, and with other powders, usually have +/-0.1 gr variation.
The loads are for a carbine - a 16” Geissele Super Duty, to be specific.

I’m currently debating between Varget and Benchmark, as I believe Bechmark is a ball powder, and may meter better. But I still have a whole pound of Varget on hand, so I’ll be able to see how it meters, too..

And thanks for the lead on the 75 gr RMR - those potentially look like a real bargain.

I think a big question is how you plan to meter the charges, and if you are planning to do single stage or progressive. Are these for a bolt gun or carbine? I figure Imma gonna drop charges for a carbine, and I do not currently have a bolt gun in .223. So I am going to drop charges, and if I am doing this on a progressive, I want to use the powder check. So I want to use some kind of ball powder since I will just meter the charges and load the rounds on a 650, so I also use the powder check. But I am just loading general use rounds, and use some at three gun.

The way I figure it is that you can load 77gn for the same effort.

If you are going to weigh each charge I say get started with the Varget, but if you meter it there can be bridging and other inconsistency, so I would for sure use a powder check if you are on a progressive.

I bought a bunch of SMK77s one day when I found them in stock, and I have a bunch loaded into nice once fired LC cases. Now I am curious about these RMR 75gn BTHPs (ETA: I forgot the link...), since they are like half price. I will probably get some and load them into random cases I bought, when you miss at three gun you just shoot again, and it not typically because of the cartridge...

[SecondsCount]

Benchmark is a short cut extruded powder, much faster burning than Varget. It will work for 77s but the velocity will be on the slower side.

It should meter pretty well but you'll get the occasional 0.2 grain variation.

[358156hp]

I have an older copy of Sierras loading manual and they list an AR-15 starting load for 77 gr SMK @ 223 pressures at 22.6 gr of Varget at 2400 FPS, maxing out at 23.9 gr at 2550 FPS. This is out of a 20 inch 1-7 twist barrel in FC cases with Remington 7-1/2 primers. Bolt action rifle loads are higher, as would be 5.56 loads. Use this data at your own risk, I haven't tried these loads and cannot make any recommendations based on simply posting information out of a book.

5.56 loads aren't shown in my manual, nor any of the "newer" powders. I now see how obsolete this manual has become. Time to upgrade!

[GyroF-16]

I have an older copy of Sierras loading manual and they list an AR-15 starting load for 77 gr SMK @ 223 pressures at 22.6 gr of Varget at 2400 FPS, maxing out at 23.9 gr at 2550 FPS. This is out of a 20 inch 1-7 twist barrel in FC cases with Remington 7-1/2 primers. Bolt action rifle loads are higher, as would be 5.56 loads. Use this data at your own risk, I haven't tried these loads and cannot make any recommendations based on simply posting information out of a book.

5.56 loads aren't shown in my manual, nor any of the "newer" powders. I now see how obsolete this manual has become. Time to upgrade!

Thank you! I have Lee and Lyman books, but was unable to find any data from Sierra, or directly referencing SMK (only “77 gr HPBT” or the like).

[GyroF-16]

The above post reminds me of a question that’s been floating in my head…

Where does one find 5.56 load data?
My rifle has a 5.56 chamber (Geissele) - is there any difference in the physical dimensions of 5.56 vs .223? Since it’s not a SAAMI spec, I’m having trouble discerning the precise difference.
My Lee dies are labeled “.223 Remington” - can I make “5.56 ammo” with them simply by increasing the charge/pressure?

ETA- never mind on the dimensional differences - some Googling has shown that the cartridges are essentially the same.
I’m still interested in where one finds 5.56 load data, however

[SecondsCount]

From the Hodgdon Reloading Data Center

BULLET WEIGHT
77 GR. SIE HPBT
CASE
WINCHESTER
PRIMER
WINCHESTER SR, SMALL RIFLE
Manufacturer Hodgdon

Powder Benchmark

Bullet Diam. 0.224"
C.O.L 2.2600
Starting Load Grs. 20.5
Vel. (ft/s) 2,523
Pressure 37,400 CUP

Maximum Load Grs. 22.8
Vel. (ft/s) 2,763
Pressure 50,000 CUP


BULLET WEIGHT
77 GR. SIE HPBT
CASE
WINCHESTER
PRIMER
WINCHESTER SR, SMALL RIFLE
Manufacturer Hodgdon

Powder Varget

Bullet Diam. 0.224"
C.O.L 2.2600
Starting Load Grs. 21.0
Vel. (ft/s) 2,528
Pressure 42,700 CUP

Maximum Load Grs. 23.7C
Vel. (ft/s) 2,737
Pressure 50,700 CUP


I found it interesting that they show Benchmark giving more velocity. My experience is that I started having pressure signs before reaching max velocity. It really depends on your chamber.