Hornady AMAX 208gr loads?

[TCCrewchief76]

No problem. Be aware that your bolt is going to see a LOT more gas volume, and that supersonic rounds are going to be a bit rougher on your weapon. The gas port specs you now have are ideal for subs...

Now go have fun,

Kevin

[Sami]

The whole thing made me reorganize my garage, much nicer now for reloading and wife should be happy as well. I think I figured out the gas block now, I guess research would have been in order earlier but glad I got it done now. I'm new to AR's so I thought the block was the one restricting the airflow, not the hole. Now that I have ideal flow for subsonics, I would have to get an adjustable block to restrict the airflow IF I wanted to shoot large amounts of supersonics. I think I'll manage for now since I built this just for subsonics.

For supersonics I have plans for bolt guns in 22-250, .308 and/or 6.5x55. Of course AR10 in .308 wouldn't be bad idea, unless you ask the wife... :)

Now I just have to set the drill press back into neck turning setup as the SI Defense uses 1.40" length with 0.01" neck diameter. By far the most time consuming task in forming brass from .223, that's why I had to use the drill press. Lathe might be a "must" purchase now so I can thread my own barrels too.

[Sami]

208gr A-Max, 10.7gr of H110 seemed to cycle without a problem and it sounded like subsonic. However, due to increased gas flow the case ruptured and left the neck on the chamber. I got it out and now I have a cast of the chamber which I will be using as reference. Looks like I neck turned a bit too much into the shoulder which caused the rupture. Live and learn, thank god!

[Retooferab]

Here is a sub load that I am playing with. This info is for the first five shots that I shot with it.



Barrel length 10.5
Port position..... pistol
Bullet type.... AMAX
Bullet weight... 208
Powder... N110..... 8.0gns 2.16oal
Velocity... 1028
Standard Deviation
Extreme Spread... 20
Accuacy.... 3/4"
temperaure... 48
altitude... 300
wind.... calm

[Alleycat]

I run 8.2 gr of VV N110
OAL of 2.234
11 inch barrel
Blackout chamber
Cyclone suppressor
V = 1050 to 1060
I've never shot them out of my 16 inch gun.

[Retooferab]

The way I came up with this load I was running 8.6 of N110 with 220smk and getting about 1035 avg. With a 2.09 oal. I just guessed that about 8gns would be close to 1030 and left my dies set at 2.09 for the SMKs. When I seated the amax they came in at 2.145 I shot them and they seem to be doing great. I hope to do more testing this week.

[Dacapster]

Any other powder loads for the subs in 208?

[Retooferab]

I am going to try some AA9 when I get a chance. I also have some 1680 but it sounds kind of loud to me. The AA9 should take even less powder than the N110 so it should be quieter.

[Rancid Coolaid]

Sami,

I've had no end of problems with H110, it seems to be very temp and position (in the case) sensitive.

I chased stringing problems in a 16" bolt gun for a good 6 months before realizing H110 just plain sucks for relatively precise shooting.

Some will disagree, probably, but that's my note of disdain for H110.
My best luck has been with #9 and lil gun.

[Sami]

Unfortunately local powder selection isn't that great. I did pick up a jug of 2400 to try a different powder. Have not been able to find 1680 or N110 anywhere so far.