ar - 15 variants 

Statements about this table:
all ar - 15 variant use flattop as a rear sight
all ar - 15 variant have forward assist
all ar - 15 variant have bayonet lug
the longest barrel length of all ar - 15 variant be 16 inch
colt model no
name
stock
fire control
rear sight
le1020
gas piston carbine
4th generation
s - 1
flattop
le1033
gas piston commando
4th generation
s - 1
flattop
le6920hb
law enforcement carbine
4th generation
s - 1
flattop
le6921
m4le carbine
4th generation
s - 1
flattop
le6921cqb
m4le carbine
4th generation
s - 1
flattop
le6921hb
m4le carbine
4th generation
s - 1
flattop
le6921sp
m4le carbine
4th generation
s - 1
flattop
le6933
m4le commando
4th generation
s - 1
flattop
colt model no
forward assist
barrel length
barrel profile
barrel twist
le1020
yes
16 in
m4
1:7
le1033
yes
11.5 in
a2
1:7
le6920hb
yes
16 in
m4 hbar
1:7
le6921
yes
14.5 in
m4
1:7
le6921cqb
yes
10.5 in
m4 hbar
1:7
le6921hb
yes
14.5 in
m4 hbar
1:7
le6921sp
yes
10 in
m4 hbar
1:7
le6933
yes
11.5 in
a2
1:7
colt model no
hand guards
bayonet lug
muzzle device
le1020
rail system
yes
a2
le1033
rail system
yes
a2
le6920hb
m4
yes
a2
le6921
m4
yes
a2
le6921cqb
m4
yes
a2
le6921hb
m4
yes
a2
le6921sp
m4
yes
a2
le6933
short ribbed
yes
a2