16" vs 20" AR-15

[Infidel]

Well I was talking more of the system itself, not so much a specific ammo. I really wanted to emphasize what type of shooting he wanted out of his rifle. I probably should have said 600 yds but 800 yards can be done with M855 (even though it will probably tumble and will most likely not be within 1 or 2 MOA it has the potential. Also, I am pretty sure, but not positive because I do not reload, that there are in fact handloads that could help achieve 1 MOA or less at 800 yds with 5.56.

Edit: That being said, I am not saying 5.56 should be used out to 800 meters, but that it can be done. As I said before, even in a SHTF type of situation you shouldn't even be engaging targets past 300 meters, because at the range in most situations, it calls for flight and not fight.

[jcabin]

Edit: That being said, I am not saying 5.56 should be used out to 800 meters, but that it can be done. As I said before, even in a SHTF type of situation you shouldn't even be engaging targets past 300 meters, because at the range in most situations, it calls for flight and not fight.

So what if you see a caravan of marauders making their way up the road to your house. I'd probably start dropping them as far out as I could. I also would probably be using 30.06 bolt or something similar.

[Infidel]

As I said in most situations, this is not most situations. If a person decides to bug in, and a caravan of marauders is making there way to your house, then by all means engage them at the furthest distance you feel confident in, with whichever system you feel confident in. However, back to what the OP wanted, a 16" carbine with a 1:9 twist is perfectly fine for clearing his house in a home defense situation, or in the SHTF bug out role. I stand by the one is none two is one adage and no one person should have only one gun. But being this is for home defense he can go with with the 16" carbine and either build an 18 or 20 in "SPR" (note term taken lightly) or get something in 6.8 7.62 7mm or what ever flavor he feels in either semi or bolt action to reach out and touch someone if need be.

[d90king]

As I said in most situations, this is not most situations. If a person decides to bug in, and a caravan of marauders is making there way to your house, then by all means engage them at the furthest distance you feel confident in, with whichever system you feel confident in. However, back to what the OP wanted, a 16" carbine with a 1:9 twist is perfectly fine for clearing his house in a home defense situation, or in the SHTF bug out role. I stand by the one is none two is one adage and no one person should have only one gun. But being this is for home defense he can go with with the 16" carbine and either build an 18 or 20 in "SPR" (note term taken lightly) or get something in 6.8 7.62 7mm or what ever flavor he feels in either semi or bolt action to reach out and touch someone if need be.

110gr 6.8 does work nicely in almost all circumstances especially if you need to go through a barrier... I shoot a fair amount of it and have grown very fond of it... I also like my 7.62x39 a lot also...

[Infidel]

110gr 6.8 does work nicely in almost all circumstances especially if you need to go through a barrier... I shoot a fair amount of it and have grown very fond of it... I also like my 7.62x39 a lot also...

I have heard good things about the 6.8 and even the 6.5. What kind of prices are you paying for 6.8? I have heard it was more expensive than 6.5 Grendel but I figure I should ask before I assume.

[Tim Ault]

What load in 5.56 takes you to 800 yds?

Loads that use the heavier than normal bullets ie: 75 and 80 gr Amax ,77 and 80 gr SMK ect. Your standard 55/62 gr. ball will shoot (travel) that far also but not with the same level of accuracy and vel./energy as the heavier bullets

[d90king]

Loads that use the heavier than normal bullets ie: 75 and 80 gr Amax ,77 and 80 gr SMK ect. Your standard 55/62 gr. ball will shoot (travel) that far also but not with the same level of accuracy and vel./energy as the heavier bullets

You don't actually believe that you are achieving MOA +/- with 77-80gr 5.56 at 800 yds do you? 800yds is .308/7.62x51 territory.... If you were saying 500-600 I might bite that it will travel the distance, but to think that you are going to achieve "groups" at that range is a little bit of a stretch. Not enough powder or weight....

6.8 will max out in the 600yds range also... Here is a side by side of 55gr 5.56 and 90gr 6.8



DATA:
http://www.snipercentral.com/223.htm
http://www.angelfire.com/art/enchanter/bullet.html

[d90king]

I have heard good things about the 6.8 and even the 6.5. What kind of prices are you paying for 6.8? I have heard it was more expensive than 6.5 Grendel but I figure I should ask before I assume.

I only shoot 6.8, I buy from SSA, prices vary from about 77 cents to 1.50 a round depending on load... The 6.5 is more of a precision round good out to 1k yards and its outside of my lane of knowledge since I don't shoot it...

I like 6.8 a lot and IMHO is the round that should be adopted by our military...

[PA Traveler]

I like 6.8 a lot and IMHO is the round that should be adopted by our military...

Once I get proficient with my AR, this is something I want to learn about.

Any comment vs .308? (Remember, I'm, a rifle noob!)

[d90king]

Once I get proficient with my AR, this is something I want to learn about.

Any comment vs .308? (Remember, I'm, a rifle noob!)

Take a class from a top tier instructor. You will walk away with plenty to work on and elevate your skill set over time utilizing the solid fundamentals learned.

6.8 can achieve close to .308 accuracy out to 300-500 yds, after that it starts to run out of legs. I have found 6.8 to be a very accurate cartridge especially at 200-300.

Indices Range
Range - yds. 0 50 100 150 200 250 300 350 400 450 500 550 600 650 700 750 800 850 900 950 1000
Velocity - ft./sec. 2775 2641 2511 2385 2263 2144 2030 1919 1812 1708 1609 1517 1430 1349 1275 1210 1152 1103 1061 1025 994
Energy - ft.-lbs. 1966 1781 1610 1452 1307 1174 1052 940 838 745 661 587 522 464 415 374 339 311 287 268 252
Path - in. -2.5 1.4 4.1 5.4 5.2 3.2 -0.6 -6.6 --14.9 -25.8 -39.8 -57.0 -78.1 -103.4 -133.5 -169.0 -210.4 -258.3 -313.4 -376.2 -447.3
Drift - in. 0.0 0.1 0.2 0.5 0.9 1.5 2.3 3.2 4.2 5.5 7.0 8.7 10.7 12.9 15.4 18.1 21.1 24.3 27.8 31.5 35.3
Time of flight - sec. 0.0 0.1 0.1 0.2 0.2 0.3 0.4 0.5 0.5 0.6 0.7 0.8 0.9 1.0 1.1 1.3 1.4 1.5 1.7 1.8 1.9

VELOCITY ENERGY TRAJECTORY
CARTRIDGE BULLET MFG. WT. TYPE MUZZ. 100 YDS. 200 YDS. 300 YDS. 400 YDS. 500 YDS. MUZZ. 100 YDS. 200 YDS. 300 YDS. 400 YDS. 500 YDS. 100 YDS. 300 YDS. 400 YDS. 500 YDS.
.308 Winchester (7.62 NATO) (U) 110 HP 3100 2718 2367 2043 1747 1483 2348 1806 1369 1020 746 536 +1.6 -7.9 -24.1 -51.9
(L) 123 FMJ 2936 2599 2286 1995 1728 1490 2355 1845 1428 1087 816 606 +1.8 -8.5 -25.9 -54.9
(CB) 125 HP 3150 2673 2243 1855 1516 1245 2755 1984 1397 955 636 430 +1.7 -8.7 -27.8 -62.8
(Hi) 146 FMJ 2822 2601 2390 2189 1998 1817 2582 2193 1852 1554 1294 1071 +1.8 -7.9 -23.1 -47.1
(P) 147 BTMJ 2780 2549 2331 2125 1931 1749 2522 2121 1774 1474 1217 998 +2.1 -9.2 -27.1 -56.1
(S) 147 FMJ 2800 2579 2368 2167 1976 1796 2560 2171 1831 1275 1053 +1.9 -8.1 -23.6 -48.0
(H) 150 SP-LM 3000 2721 2495 2212 1979 1762 2997 2466 2014 1629 1305 1034 +1.9 -7.7 -22.5 -46.2
(S) 150 SP 2820 2533 2263 2009 1774 1560 2684 2137 1705 1344 1048 810 +2.0 -8.8 -26.2 -54.8
(S) 150 SP 2900 2645 2405 2177 1962 1760 2802 2332 1927 1579 1282 1032 +1.7 -7.8 -22.9 -47.0
(S) 150 SP 2820 2488 2179 1893 1663 1405 2648 2061 1581 1193 888 657 +2.4 -9.8 -29.3 -62.0
(W) 150 SP 2900 2558 2241 1946 1678 1441 2802 2180 1672 1262 9938 692 +1.9 -6.3 18.3 -37.1
(H) 150 SST-LM 3000 2765 2541 2326 2127 1942 2997 2545 2150 1805 1506 1256 +1.5 -7.1 20.3 41.4
(H) 150 SST 2820 2560 2315 2084 1866 1644 2648 2183 1785 1447 1160 992 +2.0 -8.5 -25.2 -51.8
(H) 150 BTSP 2820 2560 2315 2084 1866 1644 2648 2183 1785 1447 1160 922 +2.0 -8.5 -25.2 51.8
(L) 150 FMJ 2789 2603 2424 2253 2088 0930 2586 2253 1954 1687 1449 1239 +1.8 -7.7 -22.4 -45.0
(S) 150 HP 2820 2610 2410 2220 2040 1860 2650 2270 1935 1640 1380 1155 +1.8 -7.8 -22.7 -46.0
(P) 150 SP 2643 2417 2203 1999 1807 1632 2326 1946 1615 1331 1088 887 +2.2 -9.4 -27.5 -56.2
(F) 150 X 2820 2610 2400 2210 2030 1850 2650 2265 1925 1630 1370 1140 +1.8 -7.9 -22.9 -46.1
(SB) 150 SP 2756 2444 2165 1903 1662 1446 2539 1994 1568 1210 920 697 +2.2 -9.6 -28.2 -60.8
(S) 150 HP 2700 2504 2316 2135 1964 1801 2428 2087 1786 1518 1284 1080 +2.0 -8.6 24.7 -50.0
(F) 150 FMJ 2820 2620 2430 2250 2070 1900 2650 2285 1965 1680 1430 1205 +1.8 -7.7 -22.3 -45.1
(R) 150 FMJ 2820 2533 2263 2010 1776 1561 2649 2137 1707 1347 1050 812 +2.0 -8.8 -26.2 -54.8
(L) 150 FMJ 2788 2599 2418 2243 2076 1916 2591 2251 1947 1676 1435 1223 +1.8 -7.8 -22.5 -45.3
(L) 155 HP 2822 2468 2141 1841 1571 1340 2729 2088 1572 1161 846 615 +2.1 -9.8 -29.9 -64.2
(RWS) 155 SP 2700 2478 2267 2066 1877 1699 2510 2114 1770 1470 1212 993 +2.1 -8.9 -25.9 -52.8
(F) 155 BTHP 2950 2740 2540 2350 2170 2000 2996 2585 2225 1905 1620 1370 +1.6 -6.9 -20.2 -40.7
(H) 165 SP-LM 2880 2655 2441 2237 2043 1859 3038 2582 2182 1833 1529 1286 +2.0 -7.9 -22.7 -45.9
(H) 165 BTSP 2700 2496 2115 1937 1770 2670 2670 2283 1940 1639 1375 1148 +2.0 -8.7 -25.2 -51.0
(RWS) 165 SP 2690 2481 2282 2092 1912 1742 2652 2257 1909 1605 1340 1112 +2.1 -8.8 -25.5 -51.8
(Hi) 165 SP 2559 2350 2150 1961 1782 1615 2400 2023 1694 1409 1164 956 +2.4 -10.0 -29.0 -59.0
(P) 165 X 2600 2425 2256 2095 1940 1793 2476 2154 1865 1608 1379 1177 +2.2 -9.3 +26.0 -52.4
(N) 165 A 2700 2459 2231 2015 1811 1623 2672 2216 1824 1488 1202 965 +2.1 -9.1 -26.9 -55.3
(F) 165 BTSP 2700 2520 2300 2160 1990 1830 2670 2310 1990 1700 1450 1230 +2.0 -8.4 -24.3 -49.0
(BH) 165 BTSP 2650 2450 2259 2077 1903 1739 2573 2200 1870 1580 1327 1108 +2.2 -9.0 -26.0 -52.7
(BH) 165 NOS 2650 2465 2287 2116 1953 1798 2573 2226 1916 1641 1398 1185 +2.1 -8.8 -25.3 -51.0
(R) 165 PP 2700 2501 2311 2129 1956 1792 2670 2292 1957 1661 1401 1176 +2.0 -8.6 -24.8 -50.1
(L) 167 HP 2690 2497 2312 2135 1966 1805 2684 2313 1983 1691 1433 1209 +2.0 -8.6 -24.8 -50.0
(L) 167 SP 2767 2564 2381 2205 2036 1875 2817 2489 2102 1803 1537 1304 +1.9 -8.0 -23.2 -46.8
(S) 168 BTM 2680 2496 2314 2143 1979 1823 2678 2318 1998 1713 1430 1239 +2.1 -8.6 -24.7 -49.9
(H) 168 BTM 2700 2491 2292 2102 1921 1751 2719 2315 1959 1648 1377 1149 +2.4 -9.0 -25.9 -52.2
(S) 168 BTHP 2650 2460 2278 2103 1936 1778 2619 2257 1936 1651 1399 1197 +2.1 -8.8 -25.6 -51.6
(SB) 168 BTHP 2628 2444 2274 2115 1958 1809 2579 2231 1930 1670 1431 1221 +2.2 -8.8 -25.5 -51.2
(CB) 168 HPBT 2600 2353 2120 1900 1696 1510 2522 2066 1677 1347 1073 851 +2.4 -10.2 -30.0 -62.1
(S) 168 BTM 2600 2410 2230 2060 1890 1740 2522 2172 1860 1584 1342 1131 +2.2 -9.2 -26.7 -53.87
(W) 168 BST 2670 2484 2306 2134 1971 1815 2659 2301 1983 1699 1449 1229 +2.1 -8.6 -24.8 -50.0
(F) 170 SP 2000 1740 1510 1313 1158 1049 1510 1145 860 651 506 416 +5.0 -20.3 -60.9 -127.4
(L) 170 FMJ 2822 2645 2474 2310 2152 2001 3007 2641 2260 2090 1749 1512 +1.7 -7.4 -21.4 -42.8
(L) 170 BTMC 2560 2384 2214 2052 1897 1749 2474 2145 1851 1590 1358 1155 +2.3 -9.4 -27.1 -54.5
(S) 175 BTHP 2600 2420 2260 2090 1940 1790 2627 2284 1977 1703 1460 1245 +2.2 -9.1 -26.1 -52.4
(S) 180 SP 2620 2274 1955 1666 1414 1212 2743 2066 1527 1109 799 587 +2.6 -11.8 -36.3 -78.2
(S) 180 SP 2620 2393 2178 1974 1782 1604 2743 2280 1896 1557 1269 1028 +2.6 -9.9 -28.9 -58.8
(P) 180 BTSP 2620 2446 2278 2117 1962 1815 2743 2391 2074 1790 1538 1316 +2.2 -9.0 -25.4 -51.3
(SB) 180 SP 2454 2119 1916 1654 1436 1255 2429 1811 1480 1103 825 629 +3.0 -12.7 -38.2 -80.6
(F) 180 NOS-HE 2740 2550 2370 2200 2030 1870 3000 2600 2245 1925 1645 1395 +1.9 -8.2 -23.5 -47.1
(SB) 180 HP 2500 2346 2205 2070 1937 1809 2521 2219 1960 1728 1499 1308 +2.4 -9.5 -27.4 -54.1
(L) 185 SP 2510 2238 1983 1746 1532 1345 2589 2057 1615 1253 964 744 +2.7 -11.6 -34.7 -72.7
(L) 185 SP 2575 2100 1681 1336 1099 966 2724 1812 1161 733 496 384 +3.3 -15.8 -51.3 -115.4
(L) 185 HP 2477 2310 2149 1995 1821 1658 2521 2193 1898 1638 1363 1129 +2.3 -9.7 -28.1 -57.1
(L) 185 BTMC 2495 2335 2181 2033 1864 1703 2558 2240 1954 1698 1427 1192 +2.4 -9.8 -27.2 -55.1
(Hi) 190 HP 2395 2235 2081 1933 1792 1659 2421 2108 1827 1577 1355 1161 +2.7 -10.8 -30.9 -61.8
(L) 200 SUB 1066 1006 959 918 882 850 505 450 408 374 346 321 +16.4 -54.2 -149.7 -289.9