Norinco Mak-90 problems

Byron Quick · March 18, 1999, 07:26 AM

My Mak-90 began having problems with case separations. Then the firing pin broke

I got the firing pin replaced and now the weapon is slam firing and the case separation problem is worse. To ascertain that it was not the ammunition, I ran about a hundred rounds of the ammo through an SKS without one separation. Multiple separations with a hundred rounds through the Mak-90.

Can this weapon be repaired? What needs to be done?

James K · March 18, 1999, 11:42 AM

This is SERIOUS. Slam firing is almost always due to an overlong firing pin and/or a weak or missing firing pin spring. The AK design is a closed-bolt design and was not intended for slam firing (unlike some open-bolt type auto weapons). Premature ignition (firing before the bolt is locked) can cause not only head separation but release high pressure gas into the action. Not good at all. To put it simply, the "gunsmith" screwed up! I would say take it back, but it might be better to try another smith. I always advise taking a gun to a "competent gunsmith", but there seem to be fewer and fewer of those. Many of today's self-styled "gunsmiths" are tinkerers who can sometimes replace a part or put a scope on a pre-drilled receiver, but who don't understand guns or gun design.

[This message has been edited by Jim Keenan (edited March 18, 1999).]

George Stringer · March 18, 1999, 11:51 AM

Spartacus, the new firing pin is possibly a little oversize, too long or there could be a burr cause it to stick in the fired postion. The only cause I've ever seen for head separation is excessive headspace. The rifle itself could need the barrel set back or the chamber may need looking at. I'd have it checked out by your local smith and see what he says. If you don't have anyone near you, e-mail me and I'll help you all I can. George

James K · March 18, 1999, 04:00 PM

Excessive headspace may be part of the problem, but I think the firing pin is firing the round before the locking lugs are fully seated; this in effect is excess headspace because the bolt is not completely closed. Of course, the rifle should be given a checkup by a competent gunsmith, which would include a headspace check.

Byron Quick · March 19, 1999, 12:12 PM

Thanks, folks. I knew it was serious. I don't like it when a weapon fires as I chamber a round

March 18, 1999, 07:26 AM	#1
Byron Quick Staff In Memoriam Join Date: November 13, 1998 Location: Waynesboro, Georgia, USA Posts: 2,361	My Mak-90 began having problems with case separations. Then the firing pin broke I got the firing pin replaced and now the weapon is slam firing and the case separation problem is worse. To ascertain that it was not the ammunition, I ran about a hundred rounds of the ammo through an SKS without one separation. Multiple separations with a hundred rounds through the Mak-90. Can this weapon be repaired? What needs to be done?

March 18, 1999, 11:42 AM	#2
James K Member In Memoriam Join Date: March 17, 1999 Posts: 24,383	This is SERIOUS. Slam firing is almost always due to an overlong firing pin and/or a weak or missing firing pin spring. The AK design is a closed-bolt design and was not intended for slam firing (unlike some open-bolt type auto weapons). Premature ignition (firing before the bolt is locked) can cause not only head separation but release high pressure gas into the action. Not good at all. To put it simply, the "gunsmith" screwed up! I would say take it back, but it might be better to try another smith. I always advise taking a gun to a "competent gunsmith", but there seem to be fewer and fewer of those. Many of today's self-styled "gunsmiths" are tinkerers who can sometimes replace a part or put a scope on a pre-drilled receiver, but who don't understand guns or gun design. [This message has been edited by Jim Keenan (edited March 18, 1999).]

March 18, 1999, 11:51 AM	#3
George Stringer Staff Alumnus Join Date: October 12, 1998 Location: Earlington KY Posts: 2,299	Spartacus, the new firing pin is possibly a little oversize, too long or there could be a burr cause it to stick in the fired postion. The only cause I've ever seen for head separation is excessive headspace. The rifle itself could need the barrel set back or the chamber may need looking at. I'd have it checked out by your local smith and see what he says. If you don't have anyone near you, e-mail me and I'll help you all I can. George

March 18, 1999, 04:00 PM	#4
James K Member In Memoriam Join Date: March 17, 1999 Posts: 24,383	Excessive headspace may be part of the problem, but I think the firing pin is firing the round before the locking lugs are fully seated; this in effect is excess headspace because the bolt is not completely closed. Of course, the rifle should be given a checkup by a competent gunsmith, which would include a headspace check.

March 19, 1999, 12:12 PM	#5
Byron Quick Staff In Memoriam Join Date: November 13, 1998 Location: Waynesboro, Georgia, USA Posts: 2,361	Thanks, folks. I knew it was serious. I don't like it when a weapon fires as I chamber a round