You can correct that by replacing those ikrule lines which this:

ikrule "lhand" touch "acr_main"
ikrule "rhand" touch "acr_main"

There's little information in these $sequence. However here is what i thought could be the problem:

ERROR: requested out of range frame on animation "@shoot1" : 16 (16)

The log mentioned "@shoot1" which is (probably) a line like this:
$animation "@shoot1" "v_rif_sg552_anims\@shoot1.smd" ikrule "lhand" ... range 0 0 20 20 ... ikrule "rhand" ... range 0 0 20 20 ...

However that @shoot1.smd possibly has 16 frames instead of 20, and ikrule range is 0 0 20 20 which is bigger than 16. That caused error.

$sequence "shoot1_layer" {
"v_rif_sg552_anims\shoot1_layer.smd"
activity "ACT_VM_PRIMARYATTACK_LAYER" 1
delta
{ event AE_CL_CREATE_PARTICLE_BRASS 2 "weapon_shell_casing_rifle_fp" }
{ event AE_MUZZLEFLASH 0 "1" }
{ event AE_CL_CREATE_PARTICLE_EFFECT 0 "muzzle_sparks_rifle follow_attachment muzzle_flash" }
{ event AE_CL_CREATE_PARTICLE_EFFECT 0 "muzzle_sparks_rifle follow_attachment muzzle_flash" }
{ event AE_CL_CREATE_PARTICLE_EFFECT 0 "muzzle_sparks_pistol follow_attachment muzzle_flash" }
{ event AE_CL_CREATE_PARTICLE_EFFECT 0 "muzzle_smoke_sniper follow_attachment muzzle_flash" }
{ event AE_CL_CREATE_PARTICLE_EFFECT 0 "muzzle_smoke_sniper_extra follow_attachment muzzle_flash" }
{ event AE_CL_CREATE_PARTICLE_EFFECT 0 "weapon_muzzle_flash_sparks6 follow_attachment muzzle_flash" }
{ event AE_CL_CREATE_PARTICLE_EFFECT 0 "muzzle_randsparks follow_attachment muzzle_flash" }
fadein 0.08
fadeout 0.2
}

$sequence "shoot1" {
"v_rif_sg552_anims\shoot1.smd"
activity "ACT_VM_PRIMARYATTACK" 1
fadein 0.2
fadeout 0.2
snap
fps 30
ikrule "lhand" touch "acr_main" contact 0 fakeorigin 0 0 0 fakerotate 0 0 0 floor 0 height 0 radius 0 range 0 0 20 20 target 1
ikrule "rhand" touch "acr_main" contact 0 fakeorigin 0 0 0 fakerotate 0 0 0 floor 0 height 0 radius 0 range 0 0 20 20 target 0
}

hmm ok thanks for the heads up ill follow it your instruction
heres the shoot $sequence im currently having a little trouble with
i will paste it in the comment

All animation (as well as sequence) have a number of frame, that error occurs because there are parameters trigger after animation ends (a.k.a out of range), could be ikrule or effects (particle, sound, etc...)
For example if your animation "@shoot1" has 16 frame but ikrule range is 0 0 100 100 then it's out of range

Hi i want to replace the XM29 oicw from the scar to SG552 but when i follow all your steps i get the error saying
ERROR: requested out of range frame on animation "@shoot1" : 16 (16)
in the compile log

I think i always overlook that glitch (when using other's mod) and i myself don't use "look_poses" in any of my mod.
Thanks for your discovery.

A suggestion, if encountering animation looping glitch when picking the gun, removing the addlayer "look_poses" from the idle sequence might solve the issue. I learned this from MrFuneral's guide.

Alrighty, thanks again.