24 Inch BHW barreled AR

[floatpilot]

This was here before the changes to the forum site. This was a 16 inch Stag carbine that I converted into a 24 inch BHW Frontier Rifle.
A 24 inch standard profile stainless target crowned barrel, a MWI 15 inch extended hand-guard. A Tubbs flat recoil spring and a titanium firing pin. So far it still has the two stage military trigger and only a 6 power fixed Leupold scope which is no longer enough for this rifle.
With gear in the butt it weighs in at 8 pounds.

I have lots more testing, but here is some of the original test to compare the two barrel lengths. This was using loads that had ben the most accurate in the old 16 inch barrel. The 24 inch allows me it do a few more things with velocity since I HAVE MORE BURN TIME.

6.8mm SPC 16 to 24 inch barrel conversion velocity and accuracy test.
16 inch barrel, Stag factory 1 in 10 twist SPC-II chamber
24 inch barrel, Black Hole Weaponry, 1 in 11 twist, SPEC II.
Fired at @ 50 degrees F. Alt 350 feet.


90 grain Sierra JHP
28.8 grains H-4198
SSA Brass, CCI-BR-4 primer
COL- 2.200 inch, Lee Crimp
16 inch = 2,908 fps and 0.40 inch group
24 inch = 3,110 fps and 0.75 inch group


100 grain Bulk mystery SP.
29.7 grains H-Benchmark
SSA Brass, Fed 205 primer
COL=2.255 inch, Lee Crimp
16 inch = 2,650 fps … Large group
24 inch = 2,750 fps--- 0.50 inch group, no flyers.

100 grain Remington SP
31.5 grains AA-2230
SSA brass, CCI-400
COL-2.225”, Lee Crimp
16 inch = 2,580 fps Group over 2 inches
24 inch = 2,765 fps… 0.75 inch group

110 grain Nosler Accubond
29.0 grains H-322
SSA Brass, CCI-BR-4
COL-2.265” Lee Crimp
16 inch = 2,554 fps and 1.0 inch group
24 inch = 2,730 fps and one ragged hole at 100 yards.

110 grain Nosler Accubond
25.8 grains AA-1680
SSA Brass, BR-4 primer
COL-2.250”, Lee Crimp
16 inch = 2,500 fps and 1.5 in group
24 inch = 2,770 fps and 0.50 inch group average






110 grain Sierra Pro-Hunter
25.8 grains AA-1680
SSA Brass, BR-4 primer
COL-2.250”, Lee Crimp
16 inch = 2,470 fps and 2.5 in group
24 inch = 2,608 fps and 1.0 inch group average

110 grain Sierra Pro-Hunter SP
30.8 grains AA-2230
SSA Brass, CCI-400
COL 2,255”, Lee Crimp
16 inch = 2,550 fps,,1.0 inch group
24 inch = 2,730 fps ..0.75 inch group


110 grain Hornady JHP.
30.8 grains, AA-2230
SSA brass, CCI-400
COL=2.255, Lee crimp.
16 inch = 2,530 fps….. 2.5 inch group
24 inch = 2,760 fps----1.1 inch group

110 grain Barnes Triple Shock
30.5 grains AA-2230
SSA Brass, CCI-400 primer,
COL-2.237, Lee Crimp
16 inch = 2,550 fps 1.5 inch group
24 inch = 2,820 fps 0.80 inch group

110 grain Hornady Factory Ammo.
110 grain BTHP
16 inch = 2,455 fps
24 inch = 2,699 fps 1.5 inch group
110 grain Ballistic tip type load
16 inch = 2,506 fps
24 inch = 2,790 fps 1.0 inch group

130 grain Sierra S.P flat base
27.0 grains H-Benchmark
SSA brass, Rem 7.5 primer
COL= 2.55 inch, Lee crimp
16 inch = 2,220 fps…1.0 inch group
24 inch = 2,480 fps and 1.0 inch group
No pressure signs.

Fired from 24" BHW barreled Stag AR, with stock military trigger, fixed 6 power Leupold scope with heavy dulplex. Using C-Mags

1.
90gr Sierra HP
29.0gr H-4198
SSA/CCI-41
2.260col LFC
3,108 fps
1.5 inch group strung vertically (see pic)

2.
90gr Sierra HP
28.8gr H-4198
SSA/CCI-41
2.260col / LFC
3,115 fps
0.75 inch group (yes better with less powder than above)

3.
90gr Sierra HP
32.0gr Benchmark
SSA/CCI-41
2.260col / LFC
2,970 fps
0.50 inch group

4.
90gr Sierra HP
31.8gr H-322
SSA/CCI41
2.255col / LFC
3,020 fps HIGH PRESSURE SIGNS
1.5 inch group

100 grain Speer HP
26.8 gr RL-7
SSA/CCI41
2.255col / LFC
2,873 fps
small group with 1st and last round flyers

100 grain Speer HP
33.0 gr Xterminator
SSA/CCI-41
2.255 col / LFC
2,900 fps 1.0 inch group

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[Deleted]

Pretty cool. Thanks for sharing. I am only at 16" SPCII at the moment but loving every bit of it.

[floatpilot]

It does OK in the accuracy department as well.
With the 16 inch barrel it was not quite enough for caribou. But it works just fine now.

These are 130 grain Sierra's at 100 yards.

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