Posted: 12/31/2012 10:55:58 AM EDT
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I've been building an AR over the past few months; I took it to the range this morning to zero a scope. I was pleased with the accuracy:)
Excuse the dirty rifle and poor cell phone pics; I'll take proper photos as I am able. Mid-Length light profile madness upper. PSA LPK and stock. LMT bcg. Troy Bravo 11" rail; YHM low-profile gas block. I sighted in at 50; the group in the pic is a 100 yard group; 1.75-ish or so inches high seems about right for a 62 grain projectile (Federal Fusion 62 grain... I have a few hunting days left). Right now I have a 3-9x40 on the rifle. After hunting season, it will get a smaller optic. http://2.mattstanfield.com/images/psa/PSAgroup3.jpg http://2.mattstanfield.com/images/psa/PSAgroup4.jpg http://2.mattstanfield.com/images/psa/PSAgroup2.jpg http://2.mattstanfield.com/images/psa/PSAgroup1.jpg |
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Nice to see someone has a good shooter. But I can't say the same for the upper PSA sent me, it's a 5.45x39 caliber and so far all I get is bullets hitting the target sideways. I've shot Wolf 60gr Hollow Points and Russian 7n6 53gr FMJ surplus. The photo's below the targets were shot at 30yds.
http://i243.photobucket.com/albums/ff307/goatbrother/545x39mmRussian7n630yds_zps3ce69d52.jpg Russian 7n6 http://i243.photobucket.com/albums/ff307/goatbrother/545ARUpperPSA_zps4ce6b22a.jpg Wolf 60gr HP I'm not too happy 
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Quoted:
Nice to see someone has a good shooter. But I can't say the same for the upper PSA sent me, it's a 5.45x39 caliber and so far all I get is bullets hitting the target sideways. I've shot Wolf 60gr Hollow Points and Russian 7n6 53gr FMJ surplus. The photo's below the targets were shot at 30yds. http://i243.photobucket.com/albums/ff307/goatbrother/545x39mmRussian7n630yds_zps3ce69d52.jpg Russian 7n6 http://i243.photobucket.com/albums/ff307/goatbrother/545ARUpperPSA_zps4ce6b22a.jpg Wolf 60gr HP I'm not too happy You need to try using better ammo before you blame the upper. |
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Quoted:
Quoted:
Nice to see someone has a good shooter. But I can't say the same for the upper PSA sent me, it's a 5.45x39 caliber and so far all I get is bullets hitting the target sideways. I've shot Wolf 60gr Hollow Points and Russian 7n6 53gr FMJ surplus. The photo's below the targets were shot at 30yds. http://i243.photobucket.com/albums/ff307/goatbrother/545x39mmRussian7n630yds_zps3ce69d52.jpg Russian 7n6 http://i243.photobucket.com/albums/ff307/goatbrother/545ARUpperPSA_zps4ce6b22a.jpg Wolf 60gr HP I'm not too happy You need to try using better ammo before you blame the upper. Ummmmmm ... Russian 7n6 is some if not the best ammo in 5.45. |
| I sent an email to PSA a week and a half ago asking for a recomendation on what ammo they recomend, still waiting for a reply. Russian 7n6 is the most commonly availible ammo for the 5.45x39mm. I expect any gun should be able to shoot commonly availible ammo. The barrel has a twist of 1-10, most rifles chambered fot 5.45 have a twist of 1-8. My suspisions are the twist rate is inadequate for the long pointy bullets commonly loaded for this caliber. I have sent 2 emails to PSA now asking for a remedy, I'm still waiting for a reply. Oh, did I mention that it took PSA 82 days to deliver this upper to me? Yes, 82 days and now I find the upper is defective or at least poorly engineered. |
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Quoted:
Quoted:
Nice to see someone has a good shooter. But I can't say the same for the upper PSA sent me, it's a 5.45x39 caliber and so far all I get is bullets hitting the target sideways. I've shot Wolf 60gr Hollow Points and Russian 7n6 53gr FMJ surplus. The photo's below the targets were shot at 30yds. http://i243.photobucket.com/albums/ff307/goatbrother/545x39mmRussian7n630yds_zps3ce69d52.jpg Russian 7n6 http://i243.photobucket.com/albums/ff307/goatbrother/545ARUpperPSA_zps4ce6b22a.jpg Wolf 60gr HP I'm not too happy You need to try using better ammo before you blame the upper. Right.......It can't be the upper 
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Quoted:
I sent an email to PSA a week and a half ago asking for a recomendation on what ammo they recomend, still waiting for a reply. Russian 7n6 is the most commonly availible ammo for the 5.45x39mm. I expect any gun should be able to shoot commonly availible ammo. The barrel has a twist of 1-10, most rifles chambered fot 5.45 have a twist of 1-8. My suspisions are the twist rate is inadequate for the long pointy bullets commonly loaded for this caliber. I have sent 2 emails to PSA now asking for a remedy, I'm still waiting for a reply. Oh, did I mention that it took PSA 82 days to deliver this upper to me? Yes, 82 days and now I find the upper is defective or at least poorly engineered. That sucks. You shouldn't have issues firing 7N6. Hopefully they'll do you right. |
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Quoted:
Quoted:
Quoted:
Nice to see someone has a good shooter. But I can't say the same for the upper PSA sent me, it's a 5.45x39 caliber and so far all I get is bullets hitting the target sideways. I've shot Wolf 60gr Hollow Points and Russian 7n6 53gr FMJ surplus. The photo's below the targets were shot at 30yds. http://i243.photobucket.com/albums/ff307/goatbrother/545x39mmRussian7n630yds_zps3ce69d52.jpg Russian 7n6 http://i243.photobucket.com/albums/ff307/goatbrother/545ARUpperPSA_zps4ce6b22a.jpg Wolf 60gr HP I'm not too happy You need to try using better ammo before you blame the upper. Ummmmmm ... Russian 7n6 is some if not the best ammo in 5.45. I stand corrected |
| Ewalt, I have the same exact situation. I've emailed as well and they refuse to respond to me. Matter of fact there was a thread on this already in the PSA section and I went looking for it and it appears to have been deleted. I was subscribed to it and it's no longer in my subscriptions. I've researched it and 1/10 twist is not suitable for 5.45x39. AK-74 is like 1 in 7.8. |
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Quoted:
I sent an email to PSA a week and a half ago asking for a recomendation on what ammo they recomend, still waiting for a reply. Russian 7n6 is the most commonly availible ammo for the 5.45x39mm. I expect any gun should be able to shoot commonly availible ammo. The barrel has a twist of 1-10, most rifles chambered fot 5.45 have a twist of 1-8. My suspisions are the twist rate is inadequate for the long pointy bullets commonly loaded for this caliber. I have sent 2 emails to PSA now asking for a remedy, I'm still waiting for a reply. Oh, did I mention that it took PSA 82 days to deliver this upper to me? Yes, 82 days and now I find the upper is defective or at least poorly engineered. OP, I seriously doubt that the keyholing problem is related to twist rate or ammo. 1. You tried two different ammos, both commercial and surplus and of different weights (different length ) and still has the same problem, 2. look at 556 AR, twist rates from 1:10 to 1:7 can stabilize a 55gr bullet w/o keyholing, so why would a 1:10 twist barrel cannot stabilize a 60 gr bullet? I honestly believe that the 7n6 is a better designed bullet than the 55gr 556. Many would disagree, but everyone is entitled to his opinion. I based mine on research. |
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Quoted:
Nice to see someone has a good shooter. But I can't say the same for the upper PSA sent me, it's a 5.45x39 caliber and so far all I get is bullets hitting the target sideways. I've shot Wolf 60gr Hollow Points and Russian 7n6 53gr FMJ surplus. The photo's below the targets were shot at 30yds. http://i243.photobucket.com/albums/ff307/goatbrother/545x39mmRussian7n630yds_zps3ce69d52.jpg Russian 7n6 http://i243.photobucket.com/albums/ff307/goatbrother/545ARUpperPSA_zps4ce6b22a.jpg Wolf 60gr HP I'm not too happy This was a problem with a lot of US made AK-74 barrels, I believe it was because they were slightly out of spec due to not being chrome lined or something like that. I think Green Mountain was the manufacturer as well. It's definitely an out of spec barrel if you're having issues with two different brands of ammo. |
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Quoted:
Quoted:
I sent an email to PSA a week and a half ago asking for a recomendation on what ammo they recomend, still waiting for a reply. Russian 7n6 is the most commonly availible ammo for the 5.45x39mm. I expect any gun should be able to shoot commonly availible ammo. The barrel has a twist of 1-10, most rifles chambered fot 5.45 have a twist of 1-8. My suspisions are the twist rate is inadequate for the long pointy bullets commonly loaded for this caliber. I have sent 2 emails to PSA now asking for a remedy, I'm still waiting for a reply. Oh, did I mention that it took PSA 82 days to deliver this upper to me? Yes, 82 days and now I find the upper is defective or at least poorly engineered. OP, I seriously doubt that the keyholing problem is related to twist rate or ammo. 1. You tried two different ammos, both commercial and surplus and of different weights (different length ) and still has the same problem, 2. look at 556 AR, twist rates from 1:10 to 1:7 can stabilize a 55gr bullet w/o keyholing, so why would a 1:10 twist barrel cannot stabilize a 60 gr bullet? I honestly believe that the 7n6 is a better designed bullet than the 55gr 556. Many would disagree, but everyone is entitled to his opinion. I based mine on research. Grain weight is not that factor that needs to be stabilized by faster twist, rather it is the increased length of the bullet that requires a faster twist. 5.45 is a smaller diameter, and a 52 gr 7n6 bullet is a bit over an inch long. 1:10 is insufficient for both the 52gr and 60gr. |