Up to 60% Off Daily Deal Products. Palmetto State Armory
The Ultimate Gun Belt, US Made, Lifetime Warranty, Free Shipping. Shop Now.
Gorilla Ammo Free Shipping when you order 10 Boxes or more.
Shop all the current Lone Wolf closeouts here

Go Back   The AK Files Forums > Rifle Forums > AK-74s

Notices

Reply
 
Thread Tools
Old 06-26-2018, 04:27 PM   #1
HuskerZ
Member
 
AKaholic #: 171990
Join Date: Nov 2013
Location: Omaha Nebraska
Posts: 109
Default Pierced primer question

Shooting one of my SAR-2s and noticed itís consistently piercing the primers with Golden Tiger 5.45 and causing a deep, bulging indentation in Silver Bear. Havenít shot this rifle much and so this is kind of a new observation. Is this likely a head space issue or just too much firing pin length? Otherwise, function is unremarkable.
HuskerZ is online now   Reply With Quote
Old 06-26-2018, 04:35 PM   #2
nalioth
Devil's Advocate & Moderator
 
nalioth's Avatar
 
AKaholic #: 5678
Join Date: Apr 2006
Location: Houston, Texas
Posts: 43,229
Default

Try more ammo brands.

The AK firing pin ain't known for its "gentle kisses".

It could be a "sensitive" run of primers in your Golden Tiger, for instance.



EDIT OMG! I completely meant to say "Your rifle is exhibiting extremely dangerous behavior and should be sent to me for safe disposal" . . .
nalioth is online now   Reply With Quote
Old 06-26-2018, 04:38 PM   #3
HuskerZ
Member
 
AKaholic #: 171990
Join Date: Nov 2013
Location: Omaha Nebraska
Posts: 109
Default

Won’t deny that. How concerned should I be about blow back (blow up?), pressure issues, etc?
HuskerZ is online now   Reply With Quote
Old 06-26-2018, 04:39 PM   #4
HuskerZ
Member
 
AKaholic #: 171990
Join Date: Nov 2013
Location: Omaha Nebraska
Posts: 109
Default

Quote:
Originally Posted by HuskerZ View Post
Wonít deny that. How concerned should I be about blow back (blow up?), pressure issues, etc?
I like my SAR2 (and my fingers), donít want a catastrophic failure.
HuskerZ is online now   Reply With Quote
Old 06-26-2018, 04:40 PM   #5
nalioth
Devil's Advocate & Moderator
 
nalioth's Avatar
 
AKaholic #: 5678
Join Date: Apr 2006
Location: Houston, Texas
Posts: 43,229
Default

Quote:
Originally Posted by HuskerZ View Post
How concerned should I be about blow back (blow up?), pressure issues, etc?
You wear eye pro at the range, right?

It ain't gonna blow up from a pierced primer.


( might blow up if you're not paying attention to potential squibs, though )
nalioth is online now   Reply With Quote
Old 06-26-2018, 04:43 PM   #6
HuskerZ
Member
 
AKaholic #: 171990
Join Date: Nov 2013
Location: Omaha Nebraska
Posts: 109
Default

Safety first. Gotcha on the pierced primer.
HuskerZ is online now   Reply With Quote
Old 06-26-2018, 05:49 PM   #7
1biggun
Curio & Relic
 
AKaholic #: 6541
Join Date: Sep 2006
Posts: 6,908
Default

Pierced primers will wreck a bolt face and enlarge the fitting pin hole as well pretty fast.

You need to get this sorted out sooner than later.

Check pin protrusion first.
Check firing pin hold diameter


If the hole becomes enlarged then the primer can blow back through it easier.

Look close at the primers that are not blown are they blowing backward in the hole any??

We recently had a thread on this were a meamber was having same issue in France in a gun he competed with .

Blown primers had eroded the hole and it was getting worse as I recall.
1biggun is online now   Reply With Quote
Old 06-26-2018, 06:00 PM   #8
cal50
Curio & Relic
 
cal50's Avatar
 
AKaholic #: 2400
Join Date: Jun 2004
Location: Ohio
Posts: 2,753
Default

Check the protrusion and if the firing pin nose has a nice rounded profile and not a sharp point.
Leaky primers are mini cutting torches and will erode your bolt.
__________________
NRA Certified Pistol Instructor / RSO
cal50 is online now   Reply With Quote
Old 06-26-2018, 06:00 PM   #9
nalioth
Devil's Advocate & Moderator
 
nalioth's Avatar
 
AKaholic #: 5678
Join Date: Apr 2006
Location: Houston, Texas
Posts: 43,229
Default

Quote:
Originally Posted by 1biggun View Post
Pierced primers will wreck a bolt face and enlarge the fitting pin hole as well pretty fast.

You need to get this sorted out sooner than later.

Check pin protrusion first.
Check firing pin hold diameter


If the hole becomes enlarged then the primer can blow back through it easier.

Look close at the primers that are not blown are they blowing backward in the hole any??

We recently had a thread on this were a meamber was having same issue in France in a gun he competed with .

Blown primers had eroded the hole and it was getting worse as I recall.
. . . . or maybe just try the simple thing first, and go with another brand of ammo . . .
nalioth is online now   Reply With Quote
Old 06-26-2018, 06:28 PM   #10
1biggun
Curio & Relic
 
AKaholic #: 6541
Join Date: Sep 2006
Posts: 6,908
Default

Quote:
Originally Posted by nalioth View Post
. . . . or maybe just try the simple thing first, and go with another brand of ammo . . .
The OP stated problems with two different types one failing and one with deep buldging.
Let's see if a third brand can finish the bolt face off.

I never contradicted you advice .
I Supplemented it .
I gave sound advice on the subject based on experience ftom this matter in simular rifles.
I further asked for clarification on if it's a pierced primer vs a blown or reverted primer back through the hole that would be further usefull in diagnosing this problem.
Blown / pierced primers can do damage on just a few shots or even just one on some rifles.

It takes what 30 seconds to a few minutes to look at or measurd the pin protrusion and check for pin hole damagd at no cost on a rifle that is having a confirmed malfunction that warrents checking the bolt at least visually . This is a common sense inspection.
I look at my bolt face on the 223 every time I'm done shooting it.

VS

Not looking it over, properly inspecting it , running out buying more ammo, going to a range , shooting it and possably doing more perminat damage anf then doing exactly what I suggested in the first place after .

OP your blowing primers on commercial ammo made to be shot in a AK 74.
Inspect your bolt face, and pin.
If ok then buy more ammo see what it does.

Wear safety glasses.

Any one know of lots of Golden Tiger percent primers and lots of silver bear exhibiting abnormal deep primer strikes???
1biggun is online now   Reply With Quote
Old 06-27-2018, 09:32 AM   #11
HuskerZ
Member
 
AKaholic #: 171990
Join Date: Nov 2013
Location: Omaha Nebraska
Posts: 109
Default

Quote:
Originally Posted by 1biggun View Post
The OP stated problems with two different types one failing and one with deep buldging.
Let's see if a third brand can finish the bolt face off.

I never contradicted you advice .
I Supplemented it .
I gave sound advice on the subject based on experience ftom this matter in simular rifles.
I further asked for clarification on if it's a pierced primer vs a blown or reverted primer back through the hole that would be further usefull in diagnosing this problem.
Blown / pierced primers can do damage on just a few shots or even just one on some rifles.

It takes what 30 seconds to a few minutes to look at or measurd the pin protrusion and check for pin hole damagd at no cost on a rifle that is having a confirmed malfunction that warrents checking the bolt at least visually . This is a common sense inspection.
I look at my bolt face on the 223 every time I'm done shooting it.

VS

Not looking it over, properly inspecting it , running out buying more ammo, going to a range , shooting it and possably doing more perminat damage anf then doing exactly what I suggested in the first place after .

OP your blowing primers on commercial ammo made to be shot in a AK 74.
Inspect your bolt face, and pin.
If ok then buy more ammo see what it does.

Wear safety glasses.

Any one know of lots of Golden Tiger percent primers and lots of silver bear exhibiting abnormal deep primer strikes???
The problem seems limited to just this rifle. I routinely shoot 4-5 different 5.45 AKs. This is the only one I have this problem with. The Silver Bear ammo looks like it primers are just on the cusp of being pierced as well. Iím going to pick up some Wolf poly in 5.45 but definitely also going to measure the firing pin, compare to other rifles, pin protrusion, etc. Probably not shooting GT out of this gun until I get this sorted out.
HuskerZ is online now   Reply With Quote
Old 06-27-2018, 06:50 PM   #12
1biggun
Curio & Relic
 
AKaholic #: 6541
Join Date: Sep 2006
Posts: 6,908
Default

Quote:
Originally Posted by HuskerZ View Post
The problem seems limited to just this rifle. I routinely shoot 4-5 different 5.45 AKs. This is the only one I have this problem with. The Silver Bear ammo looks like it primers are just on the cusp of being pierced as well. Iím going to pick up some Wolf poly in 5.45 but definitely also going to measure the firing pin, compare to other rifles, pin protrusion, etc. Probably not shooting GT out of this gun until I get this sorted out.
when you say its about ready to pierced are you seeing one single really deep hole it something that looks sort of like a hole with the center reverting backwards .

Blown primers are from over pressure where the primers are pushed back wards into the firing pin hole this is caused by over pressure or some times the wrong primer in a hand load . They can also be caused form lack of support due to a firing pin hole that's large or worn or eroded from previous issues.
I cant speak to much about the AK 74 bolts but the 223 bolts like on a bulgy have a pretty big hole already . I cant reach maximum loads with certain brand of primers on one of my 223 AKs I built . The ammo is fine in other rifles

A pierced primer is the pin punching or cutting a hole In the primer form it going to far forward or having a sharp edge . theroeticaly it could pierce with no powder in the case .

A third thing that can happen is a combination of the two were you have a pretty large and also to much pin protrusion and the pin weakens the primer and it then flows back into the primer hole .

On my hand loads with small rilfe primers I know im near max when I have a slight flow back with a dent in the middle . kind of like a zit with a hole in the center .

Pictures would help .

On a small rifle boxer primer (something you don't have) the primers outer edge will be sharp and the primers will flatten out and try and fill in the chamfer in the case when your reaching max or have exceeded it on a normal rifle with a small firing pin hole . and the primer strikes will start to flatten out as well .
Not all small rifle primers are the same and some will not show signs and some will blow primers pretty easy . primers for 22 hornet are a poor choice for 223 and similar .

Large rifle primers are harder and there more difficult to read . I have seen really hot loads in 22-250 not even show any signs .

Berdan primers are different yet ( that's what you have ) I cant give much advice on reading them . However there all supposed to be a harder type made to not slam fire with no spring loaded firing pins . I your blowing them or piercing them you likey have a rifle problem .

Im not aware of any 5.45 that does this but others here are much much more in tune with all the 5.45 x39 offerings .
1biggun is online now   Reply With Quote
Old 07-24-2018, 11:05 PM   #13
SeafoamTele
New Member
 
AKaholic #: 197013
Join Date: Jun 2018
Location: PA
Posts: 12
Default

I actually have this same problem in my 74. I mean, I wouldnt really call it a problem for me, I shoot (generally) red army ammo, which actually seems to be pretty good, but I always get a pretty big primer crater and it will pierce the cup of the primer. No other pressure signs, granted its a steel case so if i did see pressure signs, that would be alarming. However, no indication that the primer is backing out, a little flattening is apparent but no more than typical small rifle primers in a 5.56 out of an AR. I have had one critical failure though. Fired the rifle, bullet actually landed on target pretty good, but the extractor didnt grab the case. It jammed itself in the chamber some kind of good, and I had to beat it out with the cleaning rod after. That being said, the rifle was hot after a long range day and, before I put it away, I wanted to see if i could bumpfire off the last three or four in the mag for shits and giggles (not at a public range, mind you). So i maintain that this was my own fault, but maybe not.

Im interested on what others seem to say. My opinion is keep an eye on it and take care of the rifle and it'll be fine. Time has not gotten to the point of handloading 5.45 ammo for me, but when that time ultimately comes, I will become much more concerned. But thats an opinion from someone else who has spend time shooting a rifle with a similar problem. If I see reason to believe otherwise, I will definitely hesitate on shooting the rifle before fixing the issue
SeafoamTele is offline   Reply With Quote
Old 07-27-2018, 12:19 PM   #14
1biggun
Curio & Relic
 
AKaholic #: 6541
Join Date: Sep 2006
Posts: 6,908
Default

Primers piercing or blowing will perminatly damage the bolt.
The pin hole will grow and things likely will get worse.

If there being pierced round the pin and check protrusion.
If there blowing ( the primer will revert backwards into the pin hole) you have pressure problems and or pin hole that's two large.

It dosent take much to get damage.
1biggun is online now   Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

Forum Jump


All times are GMT -4. The time now is 10:59 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
©1998-2018 The AK FIles