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View Full Version : Having a Keyhole Issue. HELP!!!



lead_magnet
11-22-2012, 17:56
Okay so I bought a new Saiga in 7.62x39, standard 16 inch barrel, did the conversion myself. So it has a G-2 trigger in it. I also threaded the muzzle myself, I did this to three different rifles all at the same time and I used the bore guide to ensure my threads were inline with the bore. Using wolf ammo all the other rifles are fine. All three rifles have a YHM Phantom 2 flash hider installed with a crush washer for proper timing of the FH. The other rifles work perfectly, whereas the rifle in question is keyholeing like crazy. At 25 yards every round in punching though paper at what I'm guessing is a 45 degree angle to the paper or worse. I've looked at the flash hider and I can't find any evidence that the bullets are striking it on the way out of the tube. It also looks like the FH is properly aligned, and should be clearing the bullet on exit. What the hell could be causing this? It is literally brand new, minus the 10 or 15 rounds I've put through it. I don't want to shoot it until I figure out whats going on. Should I remove the FH and see if the problem persists with it off? Anyone else have this problem? WTF over.

Great-Kazoo
11-22-2012, 18:09
Remove hider and see what happens. All you need is a disruption in flight path of any form to cause problems. I have an alignment tool made for M1A's that will work in the AK if you need one.

Madusa
11-22-2012, 22:53
Is the crown on the barrel true? If it's not cut straight the gases get released unequally around the base of the bullet causing the bullet to leave with a wobble.

JM Ver. 2.0
11-22-2012, 22:55
Is the crown on the barrel true? If it's not cut straight the gases get released unequally around the base of the bullet causing the bullet to leave with a wobble.

Sounds like a Tim Tebow pass.....

UrbanWolf
11-23-2012, 20:26
This is my first time heard of a 7.62 keyhole, I dont have useful info but i'll follow this. Good luck.

CrufflerSteve
11-23-2012, 22:55
It's probably not the ammo since the other two work. There has been some ammo imported with .308 bullets rather than .310 but this probably isn't the problem.

If the flash hider was doing it I think you'd see signs of it, copper from the jacket but still remove the flash hider for a try.

I'll bet the crown. If you have some sort of magnifier to inspect the crown along with a strong light look for anything weird, I have a jeweler's 10x loupe and it has helped find small problems. It wouldn't take much there to cause problems.There's tools that look easy that can recrown. Maybe some builder here has them.

These are the most likely. I've heard of esoteric problems like a boogered chamber that mangles the bullet and an off center round comes out but that would be later.

An oversize barrel is also a possibility but just as remote. If you want you can slug the bore. I've only done that on old guns.

Steve

bryjcom
11-24-2012, 15:02
I highly doubt a bad crown job would be causing this unless its real bad.

Shoot it with out the flash hider first. If you still have key holes then inspect the twist rate of the barrel. Compare it to the other barrels and see if its slower. If its the same as the other barrels then you need to slug the barrel and measure the diameter. Should be .311" from land to land.

lead_magnet
11-26-2012, 15:39
I took the rifle back out yesterday and removed the flash hider. With the flash hider on, the rifle was shooting about 1'6" high at 25 meters even with the front sight post backed nearly all the way out, with the top of the post being level with the ears of the front sight base, and as mentioned, was keyholeing bad. With the flash hider removed the rifle was no longer keyholeing and was accurate and I was able to sight it in as normal.

Upon inspection of the flash hider everything appeared to be normal, but closer inspection revealed metal shavings on the inside of it between the first "baffle" so to speak and the threads. This turned out to be pieces of the jacket of previous rounds. I also observed a small deformation of the center hole evidencing that it had been stuck by the fired bullets. I compared this flash hider with another one that I had purchased some time earlier and there is a major difference. The inner diameter of the "#1" one is much much smaller than my "#2" one. They appear to be made by the same MFG though there are some differences. Maybe they have modified the design. Anyway, the "#1" flash hider was purchased on August 13th, 2012 from a retailer that for the time being, will remain unnamed. It was listed as an AK47 "Phantom A2" flash hider, new, us made compliance part. I purchased two of them, both are the same. The "#2" flash hider was purchased from the same retailer at the same price with the same item description on November 12th, 2012. The 2nd "#1" style flash hider was installed on a different rifle, that at the time is believed to be functioning correctly, though I will investigate further. It should be noted both flash hiders were correctly threaded for the 14 MM left hand thread for the standard AK muzzle. On the #1 style flash hider an unfired 7.62x39 bullet BARELY has enough clearance to pass though the flash hider, in fact if using a loaded cartridge, there is not enough room for the neck of the casing to make it though. Without a micrometer I cannot give you an exact measurement. It should also be noted that the retailer lists 7.62x39 in the item description.

I will attempt to contact YHM before I contact the retailer and see what they have to say about my findings, as I believe they made both of the flash hiders.

All of that being said, I should have checked them prior to installation. Being a dumbass that I am, I'm thinking "14x1 LH thread pitch, must be the right part". Visual inspection appeared normal, though I should have checked better, and I'm lucky I didn't have an AK explode in my face.

Pictures follow. The #1 FH is on the left, and the #2 FH is on the right. The #2 bears no markings.

Any suggestions on how to handle this?

http://imageshack.us/a/img705/909/dscf6609x.jpg

http://imageshack.us/a/img109/108/dscf6607i.jpg

http://imageshack.us/a/img22/9170/dscf6606p.jpg

http://imageshack.us/a/img29/2924/dscf6605p.jpg

http://imageshack.us/a/img835/2884/dscf6604c.jpg

http://imageshack.us/a/img35/7853/dscf6611f.jpg

Colorado Osprey
11-26-2012, 18:40
Looks like the small one is for an Ak-74

Madusa
11-26-2012, 19:27
+1 AK74

spongejosh
11-26-2012, 22:47
If the vendor sold you the wrong one I'd let them know so someone doesn't end up destroying a rifle or worse. I'd imagine you could drill out the smaller one and make it work if you don't want to send it back.