AR in x39?

240Geezer said:
So what's a "good one" as far as mags go?

Dinking around in a rare spare hour tonight I found out the following:

CProducts mag anti tilt follower tilted and jammed when loaded to 20 rounds on a 20 round mag.

Duramag mag loaded to 20 rounds fed flawlessly multiple times when loaded with 20 rounds but it's a 28 round mag.
Hey my thumb got tired.

The ammo was not the Tula I mentioned before. Tryed Red Star this time just because it was in the next can.
Click to expand...

Ive has no issues with c products 20’s. Allegedly the 28rd mags are the good ones, 30’s were early garbage.

ASC mags hit or miss, was a big miss for me but I made them work. Then I bought the new generation and they worked better.

In summary. I’ve heard and had nothing but success with C products defense duramags 28rd and under.
 
Atlantis said:
Ive has no issues with c products 20’s. Allegedly the 28rd mags are the good ones, 30’s were early garbage.

ASC mags hit or miss, was a big miss for me but I made them work. Then I bought the new generation and they worked better.

In summary. I’ve heard and had nothing but success with C products defense duramags 28rd and under.
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I got my C products 10 rounders earlier this week. BCA upper will be here on Saturday. Hopefully it all works🤞🏻
 
berdan primers will require at least a mil spec hammer spring or heavier. Also standard firing pin extrusion can be insufficient for berdan primed ammo. There are seriously many issues running 7.62x39 in an AR-15 platform. These are actually some of the minor ones.
 
92G said:
berdan primers will require at least a mil spec hammer spring or heavier. Also standard firing pin extrusion can be insufficient for berdan primed ammo. There are seriously many issues running 7.62x39 in an AR-15 platform. These are actually some of the minor ones.
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Yup. I still haven’t heard back from BCA to confirm if the firing pin I have is their enhanced version. I suppose it would be easy to file down the firing pin stop so it protrudes further? I see a lot of discussions on the AR forums about doing this with a Diamond file. Obviously you need to be careful of piercing primers etc.
 
andrew1220 said:
Yup. I still haven’t heard back from BCA to confirm if the firing pin I have is their enhanced version. I suppose it would be easy to file down the firing pin stop so it protrudes further? I see a lot of discussions on the AR forums about doing this with a Diamond file. Obviously you need to be careful of piercing primers etc.
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Just heard back. It is their enhanced firing pin. They said they can replace it. Though I doubt it will make a difference.

It’s tempting to try the firing pin modification with my drill press and a diamond file…
 
andrew1220 said:
Damn. I guess the rise armament trigger is too light for the Tula/Wolf primers. Basically 50% failure to fire rate😩
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Yeah I tried the lightened hammer/trigger springs for my PSA KS-47. Hammer strike was too light (25% fail rate). The stock springs are actually really good anyway, it's just 5-6lbs, which is a smidge more than I want for bench shooting, but at least the hammer hits hard and ignites every time.

AR-10s with the same trigger don't seem to have that issue.
 
SKumar said:
Yeah I tried the lightened hammer/trigger springs for my PSA KS-47. Hammer strike was too light (25% fail rate). The stock springs are actually really good anyway, it's just 5-6lbs, which is a smidge more than I want for bench shooting, but at least the hammer hits hard and ignites every time.

AR-10s with the same trigger don't seem to have that issue.
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I use this SBR lower for my 10.5” 5.56 and 9.25" 22lr upper so I don’t really want to mess with the trigger too much. We’ll see if I have any luck with that firing pin mod….
 
Well I got some diamond files and was able to file off some of the firing pin stop after chucking it into my drill press. So now I have more FP protrusion. The concern is knowing how much I need to take off. I took off like ~0.006" so I’ll have to test fire it and hope and pray I don’t pierce or blow out a primer….😬😬
Then again the whole entire upper including BCG cost me $233 😂
Worst case it ruins the bolt face?
 
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andrew1220 said:
Damn. I guess the rise armament trigger is too light for the Tula/Wolf primers. Basically 50% failure to fire rate😩
This is with the Bear Creek enhanced firing pin too. Didn’t try any of the golden tiger x39 I have.

I guess the only good news is that I had 0 failure to feed or extract.
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If it doesn't set off the Tula or Wolf then it will never set off the golden tiger. That was the problem I had but my hammer spring was just strong enough with the regular firing pin to set off tula/wolf/red army. So I save the GT for the AK & SKS
 
jpm said:
If it doesn't set off the Tula or Wolf then it will never set off the golden tiger. That was the problem I had but my hammer spring was just strong enough with the regular firing pin to set off tula/wolf/red army. So I save the GT for the AK & SKS
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Ah crap. I got 2 cases of GT but I still have 2+ cases of wolf/tula to burn through first which will take some time. I'll have to uncover the cases of GT ammo for testing.
 
Uzi2 said:
Have you measured the firing pin protrusion?

That looks grossly over protruded and I'll bet you'll be peircing primers.

A heavier hammer spring would be a better approach before ruining a firing pin
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Yeah the photo makes it look longer than it is. I probably should have taken off less and then tested before taking off this much.
Bear Creek already shipped me a new firing pin for free as I questioned them if it was their enhanced FP.
This might be one of the riskier/dumber things I’ve “bubba’d” with guns before…😬
 
andrew1220 said:
Yeah the photo makes it look longer than it is. I probably should have taken off less and then tested before taking off this much.
Bear Creek already shipped me a new firing pin for free as I questioned them if it was their enhanced FP.
This might be one of the riskier/dumber things I’ve “bubba’d” with guns before…😬
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Hold my beer ;-)

If you did take off too much, now you can just file down the front of the firing pin!
 
andrew1220 said:
Yeah the photo makes it look longer than it is. I probably should have taken off less and then tested before taking off this much.
Bear Creek already shipped me a new firing pin for free as I questioned them if it was their enhanced FP.
This might be one of the riskier/dumber things I’ve “bubba’d” with guns before…😬
Click to expand...
No, it looks very long. You really needed a stronger spring there, if even with such protrusion it is not enough.
Unless you got a misaligned assembly and bolt is not making it all the way properly to where it needs to be. Did you inspect duds after misfires? How did fire pin mark looked like on primer there, compared to ones that did fire ok?
 
paul73 said:
No, it looks very long. You really needed a stronger spring there, if even with such protrusion it is not enough.
Unless you got a misaligned assembly and bolt is not making it all the way properly to where it needs to be. Did you inspect duds after misfires? How did fire pin mark looked like on primer there, compared to ones that did fire ok?
Click to expand...
Yup you’re right. Still getting light strikes. I tried it with a 3lb velocity trigger and same issue. I guess the only strange thing is it always fires the first round that’s chambered but the second round always gets a light strike.
Really annoying. I don’t want to swap out springs every time I want to shoot this x39 upper.
I think I’ll have to just stick with the AK/SKS and not bother with x39 AR uppers. Definitely was a $233 gamble…
 
Picton said:
“All roads lead to wisdom, eventually. On some roads, however, the tolls are higher than others.”
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[laugh]
Rise Armament offered to send me a heavier spring for free or send me a shipping label to send the trigger back to be replaced. I think just for s&g I'll try the spring and see how much it increases the trigger pull. The Rise trigger is roughly 3.5lb. I suppose if it goes up a half pound it's not a huge deal. I'll have to ask them how much it will increase the pull.
 
I had the same problem with light strikes on a x39 upper. Tried filing, no good. I put a special x39 firing pin from windham weaponry in and works fine. The upper i got from bear creek worked fine, but i put a windham pin in it
 
andrew1220 said:
Yup you’re right. Still getting light strikes. I tried it with a 3lb velocity trigger and same issue. I guess the only strange thing is it always fires the first round that’s chambered but the second round always gets a light strike.
Really annoying. I don’t want to swap out springs every time I want to shoot this x39 upper.
I think I’ll have to just stick with the AK/SKS and not bother with x39 AR uppers. Definitely was a $233 gamble…
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So, if first round always fires fine - try on a second round next time to push forward assist button firmly to check if bolt is going all the way in. If it does not - means not enough gas, right? Easy to check if you manually pull tha charging handle 10 times and it never misfires - then it was never the pin issue.

I still think it is a spring issue.
 
paul73 said:
So, if first round always fires fine - try on a second round next time to push forward assist button firmly to check if bolt is going all the way in. If it does not - means not enough gas, right? Easy to check if you manually pull tha charging handle 10 times and it never misfires - then it was never the pin issue.

I still think it is a spring issue.
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Gas pressure has nothing to do with a bolt carrier group going back into battery. That would be a buffer/buffer spring issue.
Sounds like this whole gun in question has additive/multiple defects that need to be worked out in some type of sequence.
First, a new hammer spring......forget how it affects trigger pull........the gun is useless if it won't fire at all. And put a standard, new, unfvcked firng pin in.

Second, if it's not going into battery, get a longer, stronger buffer spring.

Third, get a heavier buffer......and LUBE THE GUN WET.

Fourth, make sure the carrier isn't being obstructed by mag feed lips, or gas tube misalignment.
 
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Tweed said:
I had the same problem with light strikes on a x39 upper. Tried filing, no good. I put a special x39 firing pin from windham weaponry in and works fine. The upper i got from bear creek worked fine, but i put a windham pin in it
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What trigger? stock milspec trigger or a lightened drop in trigger?
 
In a regular trigger setup the hammer spring strength doesn't affect trigger pull weight.
For an x39 AR the usual recommendation is a heavier hammer spring and an enhanced firing pin. To avoid light primer strikes.

For other issues like FTE, FTF you would need to tune the gun to the cartridge with buffer spring, buffer weight, gas system adjustments.

For those reasons I would not try to use that lower for multi cal uppers.

Magazines and gas tubes can be finicky and hang up bolt engagement if not aligned.
 
paul73 said:
So, if first round always fires fine - try on a second round next time to push forward assist button firmly to check if bolt is going all the way in. If it does not - means not enough gas, right? Easy to check if you manually pull tha charging handle 10 times and it never misfires - then it was never the pin issue.

I still think it is a spring issue.
Click to expand...
I should have mentioned that I was only putting one round in the mag and dropping the bolt with the bolt release each time. Call me paranoid but I did this in the event that my bubba'd firing pin caused some sort of failure. So I don't think it's a gas/bolt issue.

I'm sure it is a spring issue but I'm such a trigger whore that I don't want a super heavy trigger pull with a heavier spring. Though I can't imagine it will increase by a couple pounds with the heavier hammer spring they send me? Velocity makes a 4lb drop in trigger made for x39. I have their 3lb trigger in my other AR so going up a pound in pull isn't terrible. But I sure ain't dropping $160 on a trigger just to fire x39 [laugh]

We'll see how the heavier hammer spring works. I also asked them to send a new stock hammer spring that is currently in the Rave 140 trigger. It's probably got 5k rounds on it which is far from a lot but you wonder with x39 ammo, the slightest weakening in the spring could cause problems?🤷‍♂️
 

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