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nichud09
03-13-10, 02:06
rifle: RRA tactical car 14.7" 1:9 twist.
ammo: Ga arms 55 gr

last few times ive been to the range i noticed that the majority of my rounds are keyholing. anyone know of some causing factors of this?

i havent had the chance of trying any other types of ammo yet to see if thats the prob. as all im sitting on is a slew of ga arms canned heat ammo.

all i know is the rifle did not use to do this at all, theres only been around 3k rounds through this barrel. even with the same ammo. ive had the barrel cut down to govt profile/14.7inch from a 16", dont know if this would be a benefiting factor or not. any ideas?

bkb0000
03-13-10, 02:13
did this start immediately after getting the chop job? have you checked the bore at the muzzle? take a look and see if maybe they got too deep with the pin.. good first step. while you're doing that, peep in at the crown and make sure they didn't forget to re-crown after the chop.

after that, different ammo is definitely the first step. could just be sooper shitty ammo.

Jer
03-13-10, 10:21
Not enough length/twist to stabilize the round?

TOrrock
03-13-10, 10:23
I'd say the culprit is the cut down job.

An improperly crowned barrel with a bur at the muzzle can kick the bullet out of alignment as it leaves the muzzle.


*Edit.....also, that "Canned Heat" doesn't have a great reputation either, there have been some well publicized KB's with that stuff.

nichud09
03-13-10, 10:29
yea thats when i noticed the keyholing, after i got the rifle back from the shop. i mean my targets look like the bullet struck sideways...everytime!!

i had the work done by adco, the barrel was recrowned/threaded/pinned FH.
ive looked at everything, when looking at the crown what are some signs of damage? only thing i can see is it looks a little coarse around the crown. ill see if i can post some pics, im terrible with/at posting pics haha.
also, i cant tell if the pin is too deep either. not much help i know, i havent had, or any, experience with keyholing before.

first step, is to try some different ammo. im hoping its just that, but prob not. ive never had any bad shooting experiences with ga arms before, well other than 2 squib rounds(big pain).

nichud09
03-13-10, 10:35
I'd say the culprit is the cut down job.

An improperly crowned barrel with a bur at the muzzle can kick the bullet out of alignment as it leaves the muzzle.


*Edit.....also, that "Canned Heat" doesn't have a great reputation either, there have been some well publicized KB's with that stuff.

yeaaaa, im starting to think that too. and yes ive recently discovered through a malfunction of my own that ga arms isnt quite the best. as i mentioned i had 2 back to back squib rounds in one magazine. what a big mess lemme tell you. just glad i noticed the stuck bullet before i blew my rifle apart, or my hands. havent had any issues since, but i am slightly hesitant when shooting that ammo now. plan on re-stocking the shelves with some m855. ill keep the poopie ga arms ammo for backstock/shtf. thanks guys for your advice/thoughts.

TOrrock
03-13-10, 10:37
Contact ADCO first thing Monday morning and have them take a look at it. Tell them specifically what it's doing and the ammo used.

I'd stop shooting it and just wait. Give them a chance to take a look and make any fixes if necessary.

bkb0000
03-13-10, 14:01
yea thats when i noticed the keyholing, after i got the rifle back from the shop. i mean my targets look like the bullet struck sideways...everytime!!

i had the work done by adco, the barrel was recrowned/threaded/pinned FH.
ive looked at everything, when looking at the crown what are some signs of damage? only thing i can see is it looks a little coarse around the crown. ill see if i can post some pics, im terrible with/at posting pics haha.
also, i cant tell if the pin is too deep either. not much help i know, i havent had, or any, experience with keyholing before.

first step, is to try some different ammo. im hoping its just that, but prob not. ive never had any bad shooting experiences with ga arms before, well other than 2 squib rounds(big pain).

a "too deep" pin manifests itself in the form of a bulge or even an open sore visible within the first inch of bore, looking down the muzzle. id be sooper surprised if ADCO managed that ****up, but you never know... they do a lot of work, and mistakes happen.

the crown should look smooth and beveled toward the center of the bore

http://c3.ac-images.myspacecdn.com/images02/138/l_9e0f1177e2094f2281ebeeda105e75da.jpghttp://c2.ac-images.myspacecdn.com/images02/149/l_ad54e27f862f4c32b3db535e0b427fe1.jpg

if it looks like a sharp edge, they forgot to re-crown.. its a lot more believable that they forgot a step than that they ****ed something up.

bkb0000
03-13-10, 14:14
ADCO has good customer service.. i've had some dealings with them on both sides of the fence, and seen first hand how far out of their way they'll go to make things right.

give a call, even if you can't find anything "wrong" with the work.. i'm sure they'll help you figger it out.

arizonaranchman
03-13-10, 15:46
Contact ADCO first thing Monday morning and have them take a look at it. Tell them specifically what it's doing and the ammo used.

I'd stop shooting it and just wait. Give them a chance to take a look and make any fixes if necessary.

Ya I'd say it's the cutdown job. Assuming all other factors are the same - the only change is the barrel cut down.

Send it back to ADCO with a target and they'll make it right.

Only other time I've seen keyholing is with an AR that left the factory WITH NO RIFLING in the barrel! A damaged crown or improper rate of twist/bullet weight is about the only other factor that will give keyholing.