My new AK-15

JussRight said:

My next build will be using the Bear Creek Arsenal 7.62x39 complete upper with enhanced firing pin.

https://www.bearcreekarsenal.com/ca...arrel-1-10-twist-carbine-15-handguard-rc.html

I have a completed lower that is all AR15 milspec. Other than the recommended ASC mags will there be anything else I need to modify or purchase? Any help is greatly welcomed. Are there any other forum members that have any experience with this type of setup/ thanks, JussRight

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Hmmmm, might need a different buffer weight- Im sure someone will be along with a recommendation.

Nothing besides the 762x39 mags. only issue i have ran into with mine is some the hunting loads create failure to feeds, other then that, standard lower will be fine.

Nightlord, the standard buffer weight is fine, I have 2 windhams in 762x39 and they use the same buffer as 556.

I would try the standard buffer/spring that you have before buying anything else. Just use quality mags and like all ARs keep them oiled.

"Nobody needs an AK-15"

Sorry, couldn't resist...

NIGHTLORD40K said:

Hmmmm, might need a different buffer weight- Im sure someone will be along with a recommendation.

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No, the standard buffer/spring is good. I have a BCA 16" AR 47 on their BCA lower, works fine.

+1 on the stock buffer.
Keep us updated on the build. I’ve been thinking of building another 7.62x39 but put those plans on hold with the Russian ammo ban. But I have a prettty good stash of steel case ammo and x39 brass so I may go ahead with the build. I have 5.56, 7.62x39 and 308 on AR platforms and the x39 is by far my favorite.

A semantics question: Wouldn't an AK15 be a classic AK in 5.56, while an AR47 is an AR in 7.62 or AR74 in 5.45?

JussRight said:

Seeesh! I don't rightly know what to call it. 30 cal. American boom stick?

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It doesn't matter what you call it so long as you like it!

JussRight said:

Seeesh! I don't rightly know what to call it. 30 cal. American boom stick?

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It's not a gun, it's a high speed wireless communication device.........

sarduy said:

I would try the standard buffer/spring that you have before buying anything else. Just use quality mags and like all ARs keep them oiled.

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Yup. Start with a standard buffer and spring. If problems start, then you can play "Ask THR" about what to change. Cross that rabbit hole if/when it comes up. There is a lot of variety in buffers.

When it comes back I would check the firing pin protrusion as the russian ammo usually has very deep primer pockets (the reason for the enhanced firing pin), and if you are still getting light strikes replace the hammer spring.

The ultimate gun in this category IMHO, is the CMMG AR-15 in 7.62x39 that takes AK mags.

JussRight said:

Finally received my BCA BCG!

I have enclosed pics of the 1) New BCG, 2) previously 50/50 duds, 3) BCG in my Aero lower.

The BCA BCG is new, no wear. I wont be able to test it due to snow, been slammed with snow the last week.
It racks like butter and trigger is crisp when dry fire. I do have a 3.5lbs JMT drop in with this lower.

The ammo pictured is Red Army 122gn. Which, I may have made a mistake in purchasing
I have since acquired Wolf 122gn.

So when I get the 1st chance to test this new BCG and 2 types of ammo. I will report. Maybe my travails will help out others? heh!View attachment 1048387 View attachment 1048388

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I have 2 BCA uppers in 7.62x39. My first one, it came without the enhanced firing pin, but based on prior research I had bought one from Red X arms for $11. The specialized extractor sheared on the very first shot, rendering it a single-shot until I addressed that. I replaced with a GI spec standard extractor (meant for 5.56), and it has since run nearly flawlessly. Nearly.... on random occasions I still get a lighter strike, but will fire on the second attempt. I'm quietly considering a stronger hammer spring, but it's so rare I almost think I will leave it be.

My second upper, which has become my son's, has been good to go. This one came with the enhanced firing pin from BCA, and the extractor has held up so far.

BCA sent me a replacement extractor after I contacted them about the first one, I'm keeping it as a spare for now. Based on how the "standard" works without issue, I will simply keep a few of those in reserve. I have several 5.56 ARs that they also can fit, so universal parts are always a plus.

I have shot Red Army, Tula, Wolf, Barnaul, all steel. No brass. I own a pair of SKS's, Norinco and Yugo... I have confirmed that there are no duds in the ammo. Whatever didn't shoot from the AR still fired from the SKS. The SKS puts a DEEP indentation in the primer, FAR deeper than what your photo shows. BTW, your photo= those primers look inset, not flush?

Magazines= I use Duramags, in 10 and 28 rd. I have had very inexpensive lowers, one from PSA and the other from Karri's Guns. Y'know, the "under $150 for a complete lower" choice. They work fine.

I've slowed down with this since the Russian ammo ban, but I have to agree with others- this is a great caliber for the platform. Enough bump in the recoil to know you're shooting something, but not brutal at all.

When fooling with 7.62x39 AR uppers FIRST thing that usually needs to go for reliablity is the stock (esp. IF you replaced trigger group) hammer spring which NEEDS to be extra power over milspec ! Those Russian primers are very tough ! Even the domestic ammo seem to take more than the 5.56 need to get reliable ignition.

JussRight said:

....Other than the recommended ASC mags will there be anything else I need to modify or purchase?...

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Lotsa ammo...

I also have two AR/AK's. Standard 5.56 lower 3.5 oz. buffer and spring is perfect for them. You can get 4 to 5 rounds of 7.62x39 into a 5.56/223 magazine and still have them function. AR/AK magazines are somewhat expensive $25+shpg.

JussRight said:

Also, the BCA BCG is touted by their website as being "side staked" to enhance its performance and be able to with stand full auto? You can see the side stakes in my thumbnail. I mean, what? I don't understand that. I wont be using anything with full auto. That sounds like a marketing gimmick to me. Your thoughts and advice are greatly appreciated

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Staking the gas key screws is a must on ANY AR15 build. Full auto just exacerbates the issue. Those screws will work loose and cause all sorts of cycling issues. Un-staked gas keys were the root of many reliability problems reported by G.I.'s during the early stages of Vietnam.

Staking is a positive mechanical form of locking a fastener. Much like the use of safety wire on aircraft and race cars. Peining is another form of mechanical locking. All are considered stronger than a chemical thread locker.