Author Topic: accuracy  (Read 383 times)

Offline Jimmyk

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accuracy
« on: May 17, 2019, 02:38:00 PM »
I have 2 Valkyries, both of them assembled by me. The first one I used a PSA barrel and bcg, Aero Precision upper, lower, and hand guard, Superlative Arms adjustable gas block, CMC trigger, Magpul MOE Rifle butt stock, VG6 EPSILON 556 Stainless Muzzle Device, Ergo pistol grip, and Burris XTRII 5-50 mounted in Burris PEPR 20 MOA base/rings. The barrel is 18" stainless with 1/7 twist. I shot it about 100 times, about 50 Federal factory 75 gr fmj, some Federal factory 90 gr Fusion, and the rest were my reloads. I might have had 2 groups of 5 shots out of the bunch that grouped 1". The rest were all the way up to 3.5", all shot at 100 yds off a bench with and without bipod/bags. I contacted PSA about it and they had me ship it back to them for evaluation. I got it back Wednesday late, loaded up some 88 gr Hornady ELD and went to the range. Out of 5 groups of 5, the smallest was 2.928" and went to 3.998". I got an email from PSA telling me they had swapped my 1/7 barrel for a 1/6.5 twist in the same 18" length. What do I look for to find my problem? The scope is brand new, bought from Opitics Planet, and has only been on this rifle. Any ideas or help would be appreciated!
Thanks, Jimmy

Offline trianglevelvet

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Re: accuracy
« Reply #1 on: May 17, 2019, 05:11:41 PM »
The 20" Valkyrie upper I got from PSA (1:6.5), came with the gas block touching the handguard ever so slightly on the inside.
I took a dremel to it on the inside of the handguard to create space so that there is about a 2mm gap.

Also check the fit between upper and lower. If there's any movement, think about fixing that.

The scope your using, is it an adjustable parallax scope?
If not what is the parallax distance?

Did you clean the storage oil/grease from the inside of the barrel before shooting it?


Offline Furdown

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Re: accuracy
« Reply #2 on: May 17, 2019, 08:52:23 PM »
Jimmyk,  To get the most out of the Valkyrie you need to hand load.   My build with factory ammo didn't get me there.  Having said that even at first my hand loads were nothing to get excited about.   Then after 500 rounds thing started to settle down and even factory ammo shot better.  Federal has a new 80.5 offering out for the Valkyrie.  Give them a try.   Good luck   

Offline JC

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Re: accuracy
« Reply #3 on: May 18, 2019, 10:47:01 AM »
I had the same problems, the lighter factory loads would shoot ok but that is it, heavy rounds were 5 inches apart lol. I found the 85 grain noslers can be loaded .010 off the lands in a standard mag and if you window the mag the 90 grain match kings shoot half inch groups. I tried at least 45 different combinations trying to get it to shoot and it was a huge relief when it finally did. good luck!
Work up to it but both are under recommended max charge. CFE showed absolutely no pressure signs, 4350 was flattening primers just a little. I am taking my chronograph to the range today and will update later.

The 85 grain load that shot best for me was with CFE223 @ 24.1
The 90 match king was with 4350 @ 26.5
starline brass

Offline JC

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Re: accuracy
« Reply #4 on: May 18, 2019, 06:18:32 PM »
the 90 grain shot an average 2567 fps
the 85 grain shot an average 2484 fps

Offline Jimmyk

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Re: accuracy
« Reply #5 on: May 20, 2019, 09:15:28 AM »
I am going to try seating the bullets closer to the lands and shoot some groups. I have been seating them out to fit the magazine, so I might be single loading them. In my homemade measuring device, measuring the 88 gr Hornady ELD bullets, I have .097" to the lands, with the C.O.L. at 2.595". I might cut a window in one of my mags to be able to seat them out further and still use the mag. I have not verified the scope yet, but it was brand new, bought for this gun.

Offline Jimmyk

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Re: accuracy
« Reply #6 on: May 20, 2019, 08:43:53 PM »
I have a range report. I cut a window in one of my 10 mags and loaded 10 rounds of Hornady 88 gr ELD. 5 rounds 26.0 gr of BLC2 and 5 rounds  with 26.0 gr of CFE 223 and seated them to 2.309" COL. I shot the BLC2 rounds first and they grouped right at 1.250", with a horizontal spread, probably because the wind was 25 mph and gusting to about 40. That was way better than last week when both loads measured 3-4 inches. I loaded the CFE 223 rounds and commenced to shoot another group and only got one round off. My rifle blew up on the first shot! I've been reloading my own ammo since 1973 and this is the first time I have had a catastrophic failure! I'm glad I didn't have my left hand under the magazine, or I would be missing a left hand right now! After the shock wore off, I was going through my mind on what could have happened. I thought maybe I seated them out too far, right up against the lands and it generated too much pressure. I didn't think so, because it would have blown the primer and registered a high fps on my chrono and would have probably hit the target. I didn't have a bullet hole on my targert and it registered 24xx fps on my chrono. It blew the magazine follower, the mag floor plate, along with 3 of the 4 cartridges out of the bottom of the mag. I couldn't find the 4th. So, I got to thinking about the powder. I shoot 300 Blackout and load that with CFE Black. Did I grab that and use it to load the rounds? A 40 mile drive back home and search of my reloading bench confirmed that I indeed had grabbed the wrong powder. A costly mistake, for sure, but I'm lucky that I didn't suffer any physical damage. I think the lower receiver isn't damaged. I'm pretty sure the upper is trash. Part of the bolt carrier came loose and bent down into the mag well. I have taken the butt stock and grip off the lower and removed the hand guard, muzzle brake, gas block and gas tube off the upper. I can't get the bolt out of the barrel extension. I don't know if the barrel will be salvagable. It was looking promising.

Offline Liberator52

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Re: accuracy
« Reply #7 on: May 20, 2019, 09:00:58 PM »
OUCH ! Glad you're ok. Rifles can be fixed. Carry on !

Offline Hammerhead

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Re: accuracy
« Reply #8 on: May 21, 2019, 09:23:20 AM »
Dang, very glad to hear you are ok.

Offline Jimmyk

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Re: accuracy
« Reply #9 on: May 21, 2019, 05:49:57 PM »
I didn't find anything wrong with the lower assembly. I had to cut the upper in 2 to get to the bolt. I think the case head stuck in the chamber was prevent the bolt from coming out, because when I finally got it loose, the case head came with the bolt. I just now got the stuck case out. I applied Kroil to the chamber last night, thinking it might help. I cut some notches on a 1/4" bolt and used that to thread and screw into the neck and used washers and a nut to pull that out. It just kept coming and I couldn't understand why it went so far and with a bind on it until it popped out and I could see what happened. The case neck pulled out through the shoulder and turned the case inside out, before finally breaking off. A 3/8" tap and then a bolt and more washers got the rest of the case out. I will have to do some studying on whether or not to shoot the barrel again.

Offline Liberator52

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Re: accuracy
« Reply #10 on: May 24, 2019, 10:53:43 AM »
Don't use it. Not worth it. Hang it above your loading bench, and chalk it up to education.

Offline trianglevelvet

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Re: accuracy
« Reply #11 on: May 27, 2019, 08:04:47 PM »
💥 :o 💥
Whoa....

I'm glad to hear you weren't injured.

So, the overpressure didn't break the bolt lugs?
Gasses from the gas tube blew the carrier backwards, but it didn't unlock the bolt due to the case being super stuck in the chamber, and the excess gases vented downwards into the magazine?