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View Full Version : Exactly why do Century Arms ak74's keyhole?


Wallabing
05-24-2011, 6:06 PM
I am really unlucky, because the M74 sporter I purchaced keyholes on everyshot. I've shot it from 50 yeards, and 100 yards, and every puncture on the paper looks like the bullet is flipping in flight and impacting sideways. I've heard about this problem about centuries Tantals, but on the bulgarian ak74's?

Why does it do this, is this gun safe to shoot?


From what I've been reading, century arms doesnt give a crap to California, and wont do work on the guns, is this true?

killshot44
05-24-2011, 6:12 PM
Barrels with a "bad" bore (bore variance, groove uneveness) or a nicked-up crown will keyhole.

Have you tried diffferent ammo? Keyholing can also occur with insufficient stabilization, meaning "wrong" twist/velocity.

Wallabing
05-24-2011, 6:14 PM
I've used the surplus 5.45 x 39 from JG sales, and the brown bear 5.45 x 39, they all keyhole.

Capt Jack
05-24-2011, 6:20 PM
I vaguely remember seeing something about this in the Century flyer that I get every once in a while and I believe they blamed the surplus ammo for that. I'm pretty sure they did not use the correct barrel and it sucks if they won't take care of it because you are in CA :mad:

I would try contacting them anyway to see what they say. Good Luck and remember this about Century and their "gunsmiths" :rolleyes:
http://i203.photobucket.com/albums/aa275/Gr8fuljack/CenturyTechnician.jpg

killshot44
05-24-2011, 6:22 PM
http://i878.photobucket.com/albums/ab348/Killshot44_bucket/century20monkey1.jpg

hnoppenberger
05-24-2011, 6:25 PM
I am really unlucky, because the M74 sporter I purchaced keyholes on everyshot. I've shot it from 50 yeards, and 100 yards, and every puncture on the paper looks like the bullet is flipping in flight and impacting sideways. I've heard about this problem about centuries Tantals, but on the bulgarian ak74's?

Why does it do this, is this gun safe to shoot?


From what I've been reading, century arms doesnt give a crap to California, and wont do work on the guns, is this true?

how does the rifle group?

Wallabing
05-24-2011, 6:28 PM
Grouping is really erratic and all over the place. I shot my M74 sporter resting on a pile of towels at metcalf range.

RobGR
05-24-2011, 10:07 PM
The fact it is keyholing out to 100yrds is definitely concerning. Within 25yrds is considered acceptable b/c a long bullet like the 5.45x39 will typically yaw after leaving the muzzle but then settle in flight.

Do the "bullet test" on your brl -

http://www.youtube.com/watch?v=7MnEMzHy42E

EDIT: I guess this dude decided to make a sea sick video staring random sporadic movement, bad lighting and music in the background. Just do a google search on 5.45 bullet test. Basically it looks like you've ended up with either an old worn out brl or a US brl for 5.56x45.

hnoppenberger
05-24-2011, 10:44 PM
well, im sure the sucker will make a great wound channel.
i dont think you can do much for a problem like that short of changing the barrel?

RobGR
05-24-2011, 10:45 PM
I say you contact Century and demand (politely) that they change out the barrel free of charge. They will do everything under the sun to deny you customer service, but bug them every single day until they do. Don't get angry or abusive, like I probably would, just be the gentleman you are and push the issue until they accept the terms. When you mail it out, get delivery confirmation and someone to sign for it. The bastards may hold onto it for months, but what else can you do without forking over more money.

Some may disagree with me, but hopefully they have a better solution than mine.

Josh3239
05-24-2011, 11:43 PM
You probably got one of those .223 barreled 74s. Return it, if you can't then rebarrel it. Century seemed to really screw the pooch on those 74 rifles.

SJgunguy24
05-25-2011, 2:26 AM
Buy a surplus Bulgy 545 barrel and swap the parts yourself or at a local shop.

Chunky_lover
05-25-2011, 8:07 AM
its most likely the wrong barrel, this was all over the internet
sucks

xibunkrlilkidsx
05-25-2011, 8:28 AM
wait....they are using 5.56x45 barrels for a 5.45x39?

that is absolutely disgusting buisness tactics if im reading everyones comments correctly.

Zues
05-25-2011, 9:05 AM
If they wont replace your barrel here is an option http://whatacountry.com/ak-74-bulgarian-5.45x39mm-16-chrome-lined-barrel.aspx It will cost you some money but as long as you know someone or somewhere to do a barrel change for you.

Josh3239
05-25-2011, 10:28 PM
Yep, but I think it's incompetence more than anything.

wait....they are using 5.56x45 barrels for a 5.45x39?

that is absolutely disgusting buisness tactics if im reading everyones comments correctly.

lelandEOD
05-25-2011, 10:36 PM
Some a-holes were using 5.56 blanks turned and reamed to become 5.45 profile AK74 barrels.

One of the many reasons I steer clear of US made barrels.

thedrickel
05-25-2011, 11:27 PM
I'll give u 200$ for it.

gose
05-25-2011, 11:55 PM
The fact it is keyholing out to 100yrds is definitely concerning. Within 25yrds is considered acceptable b/c a long bullet like the 5.45x39 will typically yaw after leaving the muzzle but then settle in flight.
Do the "bullet test" on your brl -
http://www.youtube.com/watch?v=7MnEMzHy42E
EDIT: I guess this dude decided to make a sea sick video staring random sporadic movement, bad lighting and music in the background. Just do a google search on 5.45 bullet test. Basically it looks like you've ended up with either an old worn out brl or a US brl for 5.56x45.

Yes, there's a shade of truth there... some bullets might "wobble" a little bit before they settle down
Keyholing is never acceptable though. Its more in the order of going from 3/4 MOA to 1/2 MOA, or something there abouts.
The only ones that would ever say that keyholing is acceptable would be the monkeys at century.