5.56 SBR powder selection help

[sawgunner2001]

Looking for a load for a 10.5" 5.56 caliber pistol/SBR.

Intended application is normal range use/practice, <span style="font-style: italic">maybe</span> hunting nothing larger than dog sized whitetail in south GA, <span style="font-style: italic">maybe</span> a 3-gun match or two, and (lastly) having a built up supply of ammunition for when the Russians (or Democrats) invade.

Through research, I think I've decided to use bullets in the 75-77 grain weight range. Most likely, the bulk 75 grain BTHP offerings from Widener's or Pat's -OR- Hornady's 75 gr BTHP (which is what I use in my 20" AR with Varget). Reason is for terminal effectiveness at the longest possible range while still being economic. I realize the terminal effectiveness of even these bullets will only extend to 75 yards or so, but it is more than a 55gr FMJ. Am I trying to achieve the best of both worlds by achieving a terminal performer at military surplus cost? I suppose I am, and I realize the compromise I make in using a surplus bullet offering versus a commercial offering such as the Barnes TTSX. But, I only want to make one load and can't afford to be buying Barnes bullets in bulk!

What powder(s) will provide the highest muzzle velocity with this weight bullet? Popular powders that Quickload suggests are IMR 4895, Win 748, and BL-C2. *Edited to add -> QL also recommends IMR 3031. It actually put that at the top of the list. Just saw it now.

I have on hand Varget and H-4895.

Rather than take QL's word for it, I'm just checking to see what others have used in practice.

Thanks,

Sawgunner

 

[Deadshot2]

Re: 5.56 SBR powder selection help

Do you have enough twist in that short barrel?

I have a similar rifle although it has the permanent flash suppressor so it's not an SBR. I shoot 24 gr of H-4895 loads in it with 77gr bullets. Twist in my bbl is 1:8 and it's "barely" a 100 yard rifle.

 

[sawgunner2001]

Re: 5.56 SBR powder selection help

10.5" button rifled 1-8" rate of twist.

I zeroed it at 50 yds a couple weeks ago with my old bulk loading which consists of surplus 55gr FMJ bullets lit by 26.8gr of Varget in assorted cases. I didn't really measure how many MOA it was doing, nor did I chrono that load. I also fired some of my 20" AR load which is a Hornady 75gr BTHP lit by 23.5gr of Varget in LC brass. Coincidentally, they shot to the same point of impact at 50 yds. I remember the 75gr bullets grouping better and I did check for key holing which was not present (at least at 50 yds).

 

[jwp6114]

Re: 5.56 SBR powder selection help

I have been using AA2230 in my 10.5' AR's for quite some time. but mostly with 55 or 53gn bullets...

 

[D.A.T]

Re: 5.56 SBR powder selection help

BLC-2
I installed a Wolf XP spring and using an 8.25 oz buffer. I load aroune .5 gr under max.

 

[sawgunner2001]

Re: 5.56 SBR powder selection help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: D.A.T.</div><div class="ubbcode-body">BLC-2
I installed a Wolf XP spring and using an 8.25 oz buffer. I load aroune .5 gr under max. </div></div>

What barrel length and velocity are you getting?

Thanks

 

[sawgunner2001]

Re: 5.56 SBR powder selection help

Anyone else load for an SBR?

 

[Buckeye308]

Re: 5.56 SBR powder selection help

I have a 10.5" 1-7 twist SBR incoming and I was looking at using CFE223 as a powder for reloading. Didn't know if you have looked at that powder to use. I haven't had the chance to use it, but it sounds like it is getting good results.

 

[sawgunner2001]

Re: 5.56 SBR powder selection help

I hadn't thought of it. I haven't updated my edition of QuickLoad, so it doesn't have that powder in the database. Hmmm, time to upgrade QL with all these new "wonder powders" coming out...

 

[Buckeye308]

Re: 5.56 SBR powder selection help

Yea I am looking at it because I will be loading ammo for 50-75 yards, minute-of-man, kind of shooting. From what I can tell it is a fairly clean powder, but it is a spherical powder so it meters really well.

 

[sawgunner2001]

Re: 5.56 SBR powder selection help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: JWP6114</div><div class="ubbcode-body">I have been using AA2230 in my 10.5' AR's for quite some time. but mostly with 55 or 53gn bullets...</div></div>

JWP, do you have any velocity figures?

 

[country888]

Re: 5.56 SBR powder selection help

Im loading 20 gn of RL10x with 55 gn SP out of a 7.5" barrel. Im getting 2050 fps with it & great accuracy. Works great out to 200yrds.

 

[D.A.T]

Re: 5.56 SBR powder selection help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: sawgunner2001</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: D.A.T.</div><div class="ubbcode-body">BLC-2
I installed a Wolf XP spring and using an 8.25 oz buffer. I load aroune .5 gr under max. </div></div>

What barrel length and velocity are you getting?

Thanks </div></div>

2550 area with 10.5 Inch PWS with 55 Gr Z Max

 

[sawgunner2001]

Re: 5.56 SBR powder selection help

I chrono'ed two loads yesterday.

75gr Hdy BTHP
23.5gr Varget
LC Case
WIN SR Primer
2255 FPS

55gr FMJ (mixed)
26.8gr Varget
Mixed cases
WIN SR Primer
2664 FPS

The 75gr Hdy BTHP bullets could have a stiffer charge put under 'em and get 'em goin' just a little faster.

I'm hunting for some WC844 to try and get a little more velocity out of the lighter bullets. I can't really go up in the charge of Varget for the 55gr bullet load. Any more powder and there won't be room for the bullet.

 

[sawgunner2001]

Re: 5.56 SBR powder selection help

To update...I've gone a different route as far as bullet selection for the AR pistol/SBR. I've decided against relying on bullet fragmentation as a wounding mechanism and am going to use a 55gr jacketed soft point bullet, namely the Hornady Spire Point (with cannelure). It is inexpensive when purchased in bulk packaging and I was able to just now find them in stock (Midsouth Shooters Supply in case you're wondering - edit - now out of stock).

I ran out of patience waiting for powder though, and ordered 16# of Ramshot TAC. QuickLoad suggests that it doesn't give up too much compared to the powders at the top of the list, even from a short barrel. As an added bonus, it will work well with the 75gr bullets out of my 20" AR.

Regarding primers for an AR, I've been using Win SR primers and found recently that the same load that I've always used will now pierce them from time to time. Any suggestions on an alternate primer?

 

[dragonjr45]

Re: 5.56 SBR powder selection help

I use CCI #400's. I've probably fired around 1000 of them without a single problem. Ramshot TAC was the first powder I tried and the last. I have heard people say TAC is really smokey but I haven't noticed that, even suppressed.

In my 10.5" with a Noveske barrel, I'm getting amazing precision with max (223 pressure) loads of TAC with 52 AMAXs, 69 SMKs, 75 hornady match. Max loads were taken straight from the Ramshot reloading booklet. All shoot to the same point of impact. As soon as I venture into 5.56 pressure loads, precision degrades fast. I've also found acceptable performance with 50 gr. Zmax and 62 ss109 with steel penetrator. In my rifle, the 62 ss109's are the only bullet I've found that likes 5.56 pressures, which is funny because IMI M855 (with the same bullet approximately the same velocity) shoots ridiculously horrible.

You might also consider Vmax bullets as well. Inexpensive and I would think they should open up at lower velocities.

 

[chooter]

Re: 5.56 SBR powder selection help

IMR 8208 is a good choice for the223/5.56.

 

[Boogaloo]

Re: 5.56 SBR powder selection help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: JWP6114</div><div class="ubbcode-body">I have been using AA2230 in my 10.5' AR's for quite some time. but mostly with 55 or 53gn bullets... </div></div>

Me too, just be aware that Accurate 2230 varies quite a bit lot to lot. Quickload predicted a particular velocity for me with 77 grainers in my 16" AR and I measured quite a bit faster than the predicted velocity. With 2230, you may need to increase the Ba (burn rate) value in QL to get your observed velocities to mate up with your predicted velocities. Still within the 10% variance that QL is good for.

All of this is assuming that you are doing all of the other things required to get good data out of QL, such as measuring the max case capacity (H2o) of your fired, not re-sized cases etc....