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Discussion Starter #1
I’ve been enjoying working with my 22” ARP 1:6.5 3R Valkyrie barrel for long-range precision shooting. This barrel was made with the initial reamers when the Valkyrie was introduced. AR15Performance found that there were several errors in the initial chamber. Blame the mistakes on Federal, the drawings, the reamers, or be a non-believer, it really doesn’t matter. The result was the initial Valkyrie barrels that hit the market had freebores that were too long for the intended load (90 SMK) and chamber neck diameter which was too large for a .224 bullet loaded into the case neck. To compound the situation, the 90 SMK bullet was flawed causing accuracy problems that Sierra had to correct with a copper jacket change. IMO, this led to a botched introduction of a great AR15 cartridge that will beat any other production ammo that fits in the AR15 magazine with a flatter trajectory out to 1000 yards by 100 inches less drop. I had been wanting to become experienced in long-range precision shooting and had already learned to take advantage of long freebores so I didn’t hesitate purchasing the 22” ARP 1:6.5 3R Valkyrie barrel. So far, I haven’t felt disadvantaged competing next to shooters with a 6.5 Creedmoor. My experience with this barrel can be followed in this thread.

224 Valkyrie Varmint---Loading Long

Since I like to test and compare, I procured AR15Performance’s latest Valkyrie barrel which is a 20” 1:7.7 3R with a true SAAMI chamber. If you are only going to shoot out to 1000 yards, 80 grain bullets will shoot flatter than the longer, heavier VLD bullets plus the slower twist rate should provide better performance with the multitude of .224-caliber bullets available to handloaders. Here is my initial reloading and range results.
 

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Discussion Starter #2 (Edited)
At the reloading bench, distance to the lands was measured with several bullets. A flat-based GMX inserted backwards was used for the first measurement in the table below. This is a wider variety of bullets than I would use with the 1:6.5 twist barrel. Berger claims the 85.5 Hybrid will stabilize in a 1:8 twist so has been included for the initial range session. Depending on the bullet, you should see as much as 0.050” shorter jump to the lands with the SAAMI chamber. The picture line-up matches the order in the table with the 88 ELD-M and 95 SMK on the right.

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SAAMI vs Intro COAL Deltas.jpg
 

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Discussion Starter #3 (Edited)
At the range, a velocity comparison was conducted first using Federal factory ammo; the 60 Vmax, 75 TMJ, and 90 Fusion MSR. The average MV shot through each barrel is recorded in the table below. The first drop of the trigger with a 75 TMJ, I could tell there was a difference with the SAAMI chamber. The chronograph velocity was faster than the 75 TMJs had been in the 22” barrel. The primers were flat and the brass ejections were at 1 to 2 o’clock. After the fifth shot, there was a popped primer sitting on the shooting bench. All 5 of the TMJ fired cases had craters on their primers that would catch your finger nail but the swipes were light. The comparison continued with the 60 Vmax and 90 MSR. Brass ejections were 2 to 3 o’clock with the 60 Vmax and 1 o’clock with the 90 MSR. There were no craters around the firing pin strikes on the primers and only one faint swipe on the brass from the Vmax.

The same trio was then shot with the 22” barrel. All the brass landed at 4 to 5 o’clock but it’s not a fair comparison because it has an adjustable gas block which was turned down – still it is a data point. As you can see from the chronograph results shown below, the 20” barrel with the true SAAMI chamber shot faster than the 22” barrel with the longer freebore. My immediate conclusion before even getting up from the bench was the Federal factory ammo must have been developed and tested in barrels made with the initial batch of reamers that had the freebore error. The factory loads were very “hot” in the SAAMI barrel. You can see that a shorter freebore has a significant effect on chamber pressure and resultant muzzle velocity.

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Discussion Starter #4 (Edited)
A few handloads were fired with results listed below. The 55 E-Tip was included after watching a video of Todd Huey exterminating an entire sounder of hogs with the 55 E-Tip just before I left for the range. These were my guess of loads that would be near max charge that would show velocity potential. Regarding the 85.5 Hybrid, I wasn’t surprised to see the measured BC be lower than advertised. Its ogive is longer than the 88 ELD-M and 95 SMK. It looks like a 1:8 twist barrel will stabilize the bullet (no oblong holes in the paper at 100 yards), but its not stabilized enough to achieve it full BC potential. I’ve seen this with other VLD bullets like the 95 SMK in the 1:6.5 Valkyrie, 88 ELD-M in 1:8 .224, and 130 VLD in 1:11 6.8mm. Also, the 3-shot group with the 85.5 Hybrid with 1:7.7 twist was 3.6” at 100 yards – the worst group size I’ve ever seen with the Valkyrie. I will test this again to confirm if the 85.5 really is this badly affected by the twist rate. The 80 grain bullets should stabilize properly in the 1:7.7 twist, achieve their advertised BCs, and have much better accuracy.

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Discussion Starter #5 (Edited)
The range results showing the factory loads were “hot” in the SAAMI chamber were confirmed when I got home and resized the fired brass from the 20” barrel – 4 out of 5 of the TMJ cases lost their primer pockets. One of the 3 Vmax cases, the one with a slight swipe, also lost its primer pocket. I’ve heard that primer pockets go early with Federal brass but …. this indicates that some of the Federal Factory Ammo is over SAAMI max chamber pressure in a true SAAMI chamber. Measuring the fired brass showed that the chamber neck diameter was now correct, 0.256” vs 0.259”. This should help accuracy potential. The chamber diameter appeared to be tighter by about 0.002” when comparing the fired case diameter. As a side note, I’m used to Federal ammo having a crimped primer. These primers were sealed but not crimped allowing use of all my fired Federal factory brass for this new barrel without swaging the primer crimp out and not use up new Hornady brass as I explore its performance.

Conclusions (initial)
  • More testing is required to flush out the full performance potential of this barrel. An SLR adjustable gas block is now installed which should delay bolt opening and get ejected brass behind the 3 o’clock line.
  • This barrel is optimized for 80 grain bullets and lighter. The 90 Fusion MSR did fully stabilize in this barrel which should provide a viable hunting option for medium game (I will get around to testing the 90 MSR for terminal performance). If you want to hunt medium game with the Valkyrie, also consider the Barnes, Hornady, Nosler, and CavityBack monolithic bullets.
  • Despite Berger’s claim the 85.5 Hybrid will work in a 1:8 twist, I’m not a believer.
  • Beware of the 75 TMJ. I’ve found the performance of the 75 TMJ varies significantly lot to lot. I’ve learned to shot a 3-shot group from every lot and mark on the box its mv and accuracy. Some TMJ lots are sub-moa, some as much as 2+ moa. From what I’ve heard from other Valkyrie shooters, Hornady’s 75 HPBT is a more consistent and better performing round.
  • For factory ammo out to 1000-yard, it looks like the only option available is the Federal 80.5 Berger. I would expect this Berger to be a good performer.
  • There are a multitude of handloads options that will do fine in this SAAMI chamber with 1:7.7 twist including numerous 80 grain match bullets to choose from.
  • If you don’t buy a Valkyrie barrel from ARP, find out what the freebore (and chamber neck diameter) are before you order so you know what you are getting. White Oak Armament was willing to send me the reamer drawings used to cut their chambers.
I am excited to have this barrel and will focus on developing 75 Amax, 80 SMK, and the 55 E-Tip loads next. My expectations of going a 1000 yards with the 85.5 Hybrid have been lowered. I’m going to develop a 55 E-Tip load with CFE to set-up for hogs at night. The lighter recoil and faster velocity (less lead) should results in more hits on running targets. I’ve already tested the terminal performance of the 55 E-Tip (thank you, 7mmShooter, for your contribution). The E-Tip’s expansion proved up to the task for the sounders visiting my lease. I’ll track down my terminal performance results and post them later.
 

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Thank you so much for this information. I just received that same barrel yesterday so this will be a big help when I get started.
 

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I believe the customer that said he has a good load for the Berger 85s. He live around 4000ft so not sure how much difference that makes.
 
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