I read the ammo oracle and now hear word that the BC was off and the distance at which M193 will reliably fragment is much less than claimed there. Is this true? If so, what distance will it reliably fragment out of a 16" barrel?

I am trying to figure out what rifle to purchase as my all around SHTF rifle and want to know whether a 16 will do or if I need a 20"?

That's interesting.

However, you can also use stuff like the 77 gr loads which have much better fragmentation characteristics, and very good BCs as well.

I crono'd some of the m193 (lc 02, lot 39) with .224-in. 55gr. fmj with a bc. 24 in a 16" barrel and its vel. was 3037fps. for 20 shot avg., and using speers reloading manual #11s' ballistic table for a 55gr. sp w/bc. of .25( .25 bc. data used because .24 bc. datas fps. didn't go to 3000fps.), it says that a bullet started at 3000fps. will be down to 2622fps. @ 100yrds. which is below the 2700fps. threshold required for shattering bullet fragmentation, I know others that have crono'd different lots that have exceded 3100fps. but this specific lots max. range for fragmentation would be somewhere around 70yrds or so.

Unless you're in a really tight spot, or expect to be indoors mostly, carbines are a bad idea for 5.56. With a 16" barrel dont expect fragmentation past 75 yards, maybe 100 if you're lucky on a good day.

Personally, the 20" barrel is the way to go for down and dirty combat. Urban or CQB, a full size AR15 does it all. Fragmentation out to 150 yards with the ability to defeat body armor out to 500 yards is something a carbine cant match...

Quoted: Unless you're in a really tight spot, or expect to be indoors mostly, carbines are a bad idea for 5.56. With a 16" barrel dont expect fragmentation past 75 yards, maybe 100 if you're lucky on a good day. Personally, the 20" barrel is the way to go for down and dirty combat. Urban or CQB, a full size AR15 does it all. Fragmentation out to 150 yards with the ability to defeat body armor out to 500 yards is something a carbine cant match...

ooh. you got beat by a girl


Lol, just funnin' with you.

i don't think a 20" is needed in normal usages for a civilian to use an AR15...   if a civilian ever needs an AR anyways... its sure not going to be long range battles.. and if it is ... got pray for something better than 556...

carbines need to be 556...

west coast rifles need to be 308 or... if we ever get it 6.8 is the perfect round...

556 does enough for the closer ranges that carbines normally take on... and the lower recoil aids in faster shots...

6.8 allows a WC rifle to acually be a WC rifle... and engage affectively at ranges beyond 200m...

i think this chart is pretty well formed:

Just use the heavy75-77gr bullets and a 16" will take you to 200 yards.