Like many AR15 shooters, I would rather shoot more for less money. Unfortunately in the last two years shooting a lot inexpensively has been an oxymoron. Currently a shooter would be lucky to find .223 ammo for less than 35-50 cents a round which means that basically the equivalent of two quarters are flying out the ejection port with each and every trigger pull. Many of us higher volume AR15 shooters have moved over to something like a S&W M&P15-22, but then again .22LR rifle ammo has actually become more rare than .223 and nearly as expensive in some cases. More than a few fellow AR15 enthusiast have recommended AR15s converted to shoot Russian Surplus 5.45x39.


This is a tale of two 5.45x39 AR15 builds that uncover the Good and Great of two builds and a bit of Ugly revealed with one build.
WHAT IS NEEDED TO CONVERT AN AR15 TO SHOOT 5.45x39 SURPLUS AMMO?
Only two changes are required to your standard 5.56/.223 AR15, however two others are recommended. You will need a 5.45x39 chambered barrel and bolt. Depending on bolt design an “enhanced” firing pin usually included, however Ballistic Advantage uses a standard firing 5.56 pin.
Other highly recommended upgrades are an extra power hammer spring to deliver more reliable ignition on the VERY hard surplus primers. Without the extra power spring, you will have a lot of rounds that fail to detonate. A purpose built 5.45x39 AR15 magazines which will load a full 28-rounds make shooting a little more fun.
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5.45x39 Top 5.56 Nato/.223 Bottom |
Most polymer magazines such as Magpul and Troy AR15 magazines will feed and function perfectly, however, they will only allow around 20-rounds to be loaded before feeding issues occur due to the tapered case design of the 5.45x39 round. I used standard polymer Troy and Magpul AR15 magazines. Milpec steel and aluminum 5.56 mags were also tested but were shown to decrease feeding reliability and overall capacity considerably - stick with polymer mags. Magpul P-Mag followers can be cut and modified to load and reliably feed more rounds, however that is beyond the scope of this article.
The conversion process is simple if you have built an AR15 before; Swap out the barrels, move the gas block and tube over onto the 5.45x39 barrel, reattach the handguard and swap out the bolt in the existing bolt carrier group. Preferably also swap out to a higher power hammer spring. If you have the right tools, the conversion can be done in about 15 minutes.
At the time of Build #1, finding 5.45x39 barrels were a challenge, however, in my haste I found a GunTrader listing for 1:9 twist stainless steel USTactical overstock/liquidation barrels being sold for only $130. For the record Model 1 Sales does sell 5.45x39 barrel, however they are stupidly expensive at $275-$310 for just a “standard quality” level barrel. I opted for the lower cost liquidation barrel instead and was pleasantly surprised with a decent looking stainless 16” barrel.

I also ordered a Model1 Sales for a Complete 5.45x39 Bolt Assembly including a .064 enhanced firing pin - $93. The bolt arrived quickly and looks exactly like a standard bolt but with a firing pin that protrudes a bit more than a standard firing pin would. Beyond the custom parts, the bolt & barrel totaled $223 ($130 Barrel & Bolt $93) which could be easily justified in the first 1040 round Spam can.
I picked up a couple Spam cans of 5.45x39 surplus from Palmeto State Armory and hit the range. The build fed perfectly, functioned perfectly, fired perfectly, and delivered one hell of a smile on my face as the cases poured from the ejection port. There was the occasional round per magazine, which appeared to have a good primer hit, but did not ignite, however re-feeding those bad rounds fired each one. Those random duds let me work on my jam clearing drills.
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25-yard Group Approx 2" |
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50-yard Group Approx 5" |

After over a 1000-rounds of various lots of 5.45x39 rounds and bullet weights, the barrel was still delivering keyholing rounds down range. I recrowned the barrel in hopes that it was a bad crown versus just not enough twist in the 1:9 rifling to stabilize the round. Although the crowning delivered a marginal improvement, it is now clear that a 1:9 twist is not enough to stabilize the round coming out of an AR15 format rifle or the barrel was improperly drilled to 5.56 diameter. Lesson learned do not buy a 1:9 twist 5.45x39 barrel on the cheap and again my hunt continued for a better barrel.

The rebuild uses a very low profile Fortis gas block, YM Chrome M16 carrier, Geissele Mark IV ultralight forend, Fortis upper, Anderson Manufacturing lower, Barnes Precision parts kit, YHM flip up sights, ALG trigger, and Anderson Manufacturing flash hider, charging handle, carrier, and gas tube. In the end the build was well equipped and fun to shoot.

5.45x39 BUILD #2 - BALLISTIC ADVANTAGE BARREL, BOLT, & EXTRA POWER SPRING

Some of BA’s most notable OEM relationships are the very well regarded Spikes Tactical 5.45x39 uppers which BA provided the bolts and barrels for. Apparently BA is the only company around which has done a ton of R&D on the 5.45x39 surplus rounds in the AR15 platform and developed barrels and bolts which allegedly deliver superb accuracy and reliability.
Unlike many 5.45x39 barrel manufacturers, Ballistic Advantage believes the round needs a faster 1:8 twist barrel and BA also does something different on their bolt.
The Ballistic Advantage barrel received would be considered super premium grade. It features a flawless external finish, mirror internal bore, match recessed crown, full melonite coating, and Fail Zero Barrel extension. It is a gorgeous barrel for $255 and far from the quality of the other 5.45x39 barrel I picked up on the cheap.
BA also goes the extra mile to assure reliability of the bolt and ignition with a custom designed bolt which uses a standard AR15 firing pin. They do this by specially designing the bolt which allows a standard AR15 firing pin to strike deeper into the primer for positive ignition versus needing an extended firing pin.


Unlike the cheapo liquidation barrel that hurled bullets sideways downrange, the BA barrel performed amazingly well. A smile curled on my lips as my first quick three-shot sight-in group delivered a .5” group at 27-yards with all round holes. The next couple groups shrank even smaller to around .25” while finishing up the sight in with the Eotech optic setup. It was obvious this barrel is a shooter and even at 100-yards still delivered sub-1.25” groups with the Eotech. The groups shrank further with a higher powered optic. Look for a future article on the surprisingly long range accuracy of the Ballistic Advantage 5.45x39 barrel.



The entire build is extremely light and so custom it screams to be shot a lot. How could you now want to hammer rounds through it? It is amazingly accurate with just standard cheap surplus 5.45x39 ammo and with the muzzle brake, rifle length buffer, and mid-length gas system it delivers a soft shooting tuned 3-Gun style AR15.
FINAL THOUGHTS
The question many will ask is whether they should lay down the initial investment for the surplus 5.45x39 conversion.
Looking at cost savings - if you are a casual shooter that only shoots a few hundred rounds a year with your AR, then a conversion may not pay out for you unless you are just curious about the round. On the other hand, if you do dump 1000s of rounds downrange, a 5.45x39 conversion can pay for itself in your first $380 - 2080 rounds worth of 5.45x39 surplus ammo and can save money every round after that.
Beyond the cost savings, the 5.45x39 round is just as powerful a round as the .223 Remington or 5.56 Nato round. Arguably it is more efficient from a defense perspective and with the Ballistic Advantage barrel and bolt, it can also be just as accurate all for less than half the price per round.223/5.56.
The only real downside is that 5.45x39 surplus rounds are corrosive. This sounds scary, however keep in mind, I have pushed over 6000 rounds (as of March 2014) through a non-anodized ASA receiver in Build #2. Aluminum is one of the most reactive metals and should show pitting quickly, however, I do not have a spot on the receiver. The main reason I have had no damage on any parts is that a simple but thorough Windex or soap and water bath after you return home neutralizes the corrosive issues. Follow the bath up with a compressor blow-off, clean the bore as usual, spray down the surfaces with WD-40. Really no more than you should do with any other gun. That noted I have seen people intentionally maintain conversions poorly just to see what happens and generally the damage is nothing too serious. Following a religious cleaning regimen right after shooting will assure a long lived barrel and internals
The only component between the two builds that are a little ugly that did not perform as expected was the 1:9 twist liquidation barrel. Look for a full review on the cool parts used in each of these builds. Meanwhile, I need to get back to the range and shoot more... for less.
Build #1
Anderson Manufacturing Lower Receiver & Flash Hider - http://www.andersonrifles.net/
Geissele Mark IV Forend - http://geissele.com/
YHM - Sights - http://yhm.net/
Barnes Precision Machine lower parts kit - http://www.usamade-ar15parts.com/
Fortis - Upper Receiver - http://fortismfg.com/
Young Manufacturing Carrier - http://www.youngmanufacturing.net/
Model 1 Sales - Bolt - http://www.model1sales.com/
The Mako Group - Funiture - http://www.themakogroup.com/
The Mako Group - Funiture - http://www.themakogroup.com/
Build #2
Ballistic Advantage - www.ballisticadvantagellc.com - https://www.facebook.com/BallisticAdvantage
ASA - American Spirit Arms - http://www.americanspiritarms.com/
AP Customs - http://www.apcustomusa.com
ASA - American Spirit Arms - http://www.americanspiritarms.com/
AP Customs - http://www.apcustomusa.com
Ace Ultra Light Stock - http://riflestocks.com/store/
AXTS - Rainer Arms Ambidexterous Charging Handle
Barnes Precision Machine lower parts kit - http://www.usamade-ar15parts.com/
Eotech - EXPS2 & G33.STS Multiplier - http://www.eotech-inc.com/
ALG - Trigger - http://algdefense.com/
Houlding Precision - Curse Brake - http://www.houldingprecisionfirearms.com/
Fail Zero Carrier - http://www.failzero.com/
13 comments:
Did you slug the first barrel? I got one that performed similarly, although it's a different brand. Turns out it's pretty much a 5.56 barrel with a 5.45 chamber, so it's not the fault of the twist rate.
Did you use or need a higher powered hammer spring?
he high power hammer spring does improve ignition, however I run most of my lowers without them with these uppers. The best option I found was a HiperFire triggers which offer match grade feel with very high hammer fall trigger force.
I have not slugged the barrel, but I am pretty sure that is the issue.
So I can use a standard ar15 Carrier? I will just need a 5.45x39 Bolt? and will these two work together?
Yep - you can use a standard carrier and will only need the 5.45x39 bolt and the barrel.
What buffer and tube do you recommend for the BA 16'' mid-length barrel? Thanks
I just built a BA set up with the 20 inch barrel and bolt. I am not so happy with the performance. I think most of the problem is in the mags not feeding correctly. What do you suggest? How about the buffer spring? I just used a standard one.
Shoots very straight when it works. I didn't have any key holes even at 100 meters.
I just built a BA set up with 20 inch barrel and bolt. I hate it so far. Mainly due to feed issues I think. It will fire and extract but won't feed. What mag would be best? I tried metal ones designed for 5.45 but they were the worst. A modified Magpul worked sometimes. Help me figure this out so I don't have to be a hater. I have lots of shooting to do.....
Any buffer tube will work fine with a stock spring and buffer. I used a rifle length, however a carbine length will work just as well
Well the mag reliability is he biggest issue with these builds. Personally I would highly suggest. Sticking with Magpul mags and only loading 15-18 rounds in an un modified magazine. With modification you can get into the 25 -round range. The other issue which delivered some aggravation was ignition reliability. You do need an extra power spring to get the best reliability. My current setup is a HiperFire 24 trigger with a stock Ar15 hammer spring. This boosts the hammer force and is now only have 1 round in about 400 that which fail it fire.
What modification did you do to the mags? Are the mags you're talking about Magpul AR/5.56 mags?
Are these Magpul AR/5.56 mags? What mod did you do?
Thanks
If you don't want a high capacity magazine, then a standard magpul 5.56 mag works fine. For high capacity around 25+ rounds, I basically removed the anti-tilt follower legs on the follower. This allows the magazine follower to tilt with the stocked tapered case 5.45x39 rounds.
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