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Discussion Starter #1
Kind of thinking out loud here, but also looking for feedback from those who shoot a lot of rounds every year. I shoot several thousand round per year myself, but they have been almost exclusively from 223 Rem and 7mm-08 rifles. My 6.8 SPC II and 224 V spend more time in the safe than in the truck or in my hands in the field.

1.) With the introduction of 95gr Sierra super streamline boolitz would it make sense to put a 224 Valkyrie on a SA receiver with a 24-26in tube to compete in PRS? Could the Valk beat out the heavy 6.5s? An AI'd 6.5X55 on a modern medium length action would have a ton more case capacity, but with the more managable recoil would the Valk still be a realistic competitor? I mean if you put a good brake on you can tame the felt recoil of just about any competition gun. I don't know if I'd enjoy shooting 200+ rnds of 300WSM regardless of the brake.

2) Seeing that a PRS season could include 10+ matches would the barrel life come into play? How much would it cost to screw new lawnmower axels on a big overbore gun a couple times a year? I would speculate that the Valk should go 2500 or better rounds before throat erosion began to degrade accuracy. I can see a heavy charge of H4350 from an AI'd 6.5X55 or 6.5-47 eating throats much faster. I only got 1600 from my 260 AI before I had to set it back. (300rnds fire forming brass with 123 A-Max with RL15 plus 1300rnds with RL26 pushing 140gr Nosler CC at 2970)

3) Is there a better round to do the same thing a Valk does if you go to the longer COAL of a SA bolt gun?


Your thoughts and observations will be appreciated.

Thanks in advance,
Khavic
 

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Honestly, I'm not a wildcatter nor any kind of "P.O. Ackley" gunsmith, but I do have to wonder:
The .224 Valk, basically, is a "souped up" .22 cal center fire.
What's wrong with some exploration with the heavier Valk bullets and the .22-250 Rem., .220 Swift or maybe the .225 Win?
There are other .22 "Screamers" out there that might even do the heavier bullets justice.
That said, I don't have problems with developing new cartridges to new heights.
At what point does "duplication" happen and is there any "real" advantage to having several cartridges capable of equal(?) ballistics?
 

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.22-250 and Swifts typically don't have fast enough twist rates to shoot the VLD .224 bullets. I have a 22" 224 Valkyrie and shot two sniper matches this year and didn't feel handicapped against the guys with Creedmoors. I have a longer throat and load longer than mag length out to 2.375" in an AR. With a bolt gun you could have the throat with closer tolerance for increased accuracy and longer freebore to maximize case capacity. BTW, I have yet to test the 95 SMKs at long distance to confirm the BC with 6.5 twist. 88 ELD-Ms are spot on as advertised. The 95 SMK were around 0.55 BC using the velocity decay with a doppler radar. It may be they hadn't gone to sleep yet and will achieve 0.6 downrange with a 6.5 twist.
 

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Check out the 6 mm Creedmore, with the 108 gr bullet it comes within 2/10 inch at 1000yds of the 6.5 Creedmore as for trajectory. Not sure of barrel life but could be good. The .224 V with 95 gr bullet velocity should be low enough to not erode barrels too quickly. 3000 fps seems to be the magical number for fast bore erosion.
 

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Khavic, with as much as you want to shoot, you would be changing a 6mm Creedmoor barrel out at least once a year. In the last competition I was in, guys were lugging around 20+ pound bolt guns with 28" barrels. Not my idea of fun.
 

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Discussion Starter #6
Khavic, with as much as you want to shoot, you would be changing a 6mm Creedmoor barrel out at least once a year. In the last competition I was in, guys were lugging around 20+ pound bolt guns with 28" barrels. Not my idea of fun.

I tend to agree.
 

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.22-250 and Swifts typically don't have fast enough twist rates to shoot the VLD .224 bullets. I have a 22" 224 Valkyrie and shot two sniper matches this year and didn't feel handicapped against the guys with Creedmoors. I have a longer throat and load longer than mag length out to 2.375" in an AR. With a bolt gun you could have the throat with closer tolerance for increased accuracy and longer freebore to maximize case capacity. BTW, I have yet to test the 95 SMKs at long distance to confirm the BC with 6.5 twist. 88 ELD-Ms are spot on as advertised. The 95 SMK were around 0.55 BC using the velocity decay with a doppler radar. It may be they hadn't gone to sleep yet and will achieve 0.6 downrange with a 6.5 twist.
There are several offerings in 22-250 out there with fast twist barrels for the heavies. 1 in 9 and even 1 in 8. I had one in a Bergara that was 1 in 9 twist but never really got started with it. 1 in 8 twist should shoot 90gr quite well. Of course, still talking about hand loading since as far as I know no one does factory loads 80s and 90s in the 22-250.
 

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Discussion Starter #8
There are several offerings in 22-250 out there with fast twist barrels for the heavies. 1 in 9 and even 1 in 8. I had one in a Bergara that was 1 in 9 twist but never really got started with it. 1 in 8 twist should shoot 90gr quite well. Of course, still talking about hand loading since as far as I know no one does factory loads 80s and 90s in the 22-250.
I think I may be talking about my Valkyrie project too much among my friends because now one of them just ordered an 8 twist 22-250 barrel. He seems to think his 22-250 with 70gr RDF will toast my 224 V with 95gr SMK's at 1000 and beyond.... I think he's going to toast his throat and constantly be fighting accuracy issues due to rapid erosion changing the jump distance. I guess by this time next year we will know for sure. He has half heartedly committed to shooting five matches with me next year.
 

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I think I may be talking about my Valkyrie project too much among my friends because now one of them just ordered an 8 twist 22-250 barrel. He seems to think his 22-250 with 70gr RDF will toast my 224 V with 95gr SMK's at 1000 and beyond.... I think he's going to toast his throat and constantly be fighting accuracy issues due to rapid erosion changing the jump distance. I guess by this time next year we will know for sure. He has half heartedly committed to shooting five matches with me next year.
You may be right if he shoots a lot of matches but 22-250 with 35-45 gr projectiles are pretty well known to be barrel burners. I would think with 70-90 grain projectiles it would be much less due to lighter powder charges.
 

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I wouldn't go with the 6 mm Creedmoor. Barrel burning for sure. Doesn't the 7mm 08 compared favorably to the 6.5 Creedmoor? I think I've read they are more common in PRS than .308. Less recoil compared to .308.
 

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1 in 8 twist should shoot 90gr quite well.
1:8 twist is insufficient for 88 ELD and heavier .224 bullets. I've tested 88 ELDs in 1:8 twist and shot from a 24" WOA 1:8 at 250 yards. Muzzle velocity was in the Valkyrie's range at 2625 fps. No apparent yawing of the impacts. 3 grouped 1/2 MOA then had a flyer.

Post-range data analysis of down-range LabRadar velocities showed the bullet was not stabilized enough to achieve full BC potential. The measured BC of the 88 ELD-M in 1:6.5 twist has repeatably been 0.545 (G1) as it was during the above range session. In the 1:8 twist, the BC was 0.442 (G1). I have become a believer in having amble twist. As I stated before, I am not sure that the 1:6.5 twist is stabilize the 95 SMK sufficient to get its advertised BC of 0.6. The best I've achieved has been 0.56 but need to test trajectory drop at 1000 yards to verify.
 

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1:8 twist is insufficient for 88 ELD and heavier .224 bullets. I've tested 88 ELDs in 1:8 twist and shot from a 24" WOA 1:8 at 250 yards. Muzzle velocity was in the Valkyrie's range at 2625 fps. No apparent yawing of the impacts. 3 grouped 1/2 MOA then had a flyer.

Post-range data analysis of down-range LabRadar velocities showed the bullet was not stabilized enough to achieve full BC potential. The measured BC of the 88 ELD-M in 1:6.5 twist has repeatably been 0.545 (G1) as it was during the above range session. In the 1:8 twist, the BC was 0.442 (G1). I have become a believer in having amble twist. As I stated before, I am not sure that the 1:6.5 twist is stabilize the 95 SMK sufficient to get its advertised BC of 0.6. The best I've achieved has been 0.56 but need to test trajectory drop at 1000 yards to verify.
Are you talking in the Valkyrie or 22-250? Because it isn't the same thing at all. A 22-250 can push an 80gr projectile to 3150 MV. It doesn't need as fast a twist rate as the same bullet traveling at Valkyrie speeds or .223 for that matter.
 

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Though increased velocity does improve bullet stability, it is insignificant compared to the benefits of a faster twist rate. The stability calculations below for the 88 ELDs shot from 1:8 twist above are using the JBM calculator which provides an approximation of stability. The top is that day's range conditions, the middle is standard day, and the bottom was the range conditions at the sniper match I shot earlier this year. I've had bullets be green and not stabilize and some be yellow and stabilize (its just an estimate). In this case, none of the conditions were enough to stabilize the 88 ELD-M to achieve its full BC potential. A 20% BC deficit is a lot to make up (0.442 (G1) actual in a 1:8 vs 0.545 (G1) advertised). The faster speed of the .22-250 might improve stability by 5% but it would still be insufficient, in my experience. The longer 95 SMK would be even less stable than the 88 ELD-M.
 

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You obviously know more than I do about it. I was just going on reports of the 90 SMKs being used with success in 1000 yard matches from 1:8 twist barrels with MV of 3100fps.
I was mainly planning to use 75gr GMX for deer hunting with mine but it never panned out. Someone came along and talked me out of it before I ever got to do any load work. I don't have much beyond 100 yards for a range without going to a club or public range and that isn't something I really care to do anyway. Ended up with a 204 Ruger to satisfy my need for speed.
 

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Discussion Starter #15
The 25gr difference between 70 and 95gr projectiles with similar profiles and matching diameter should be too much to overcome for the 22-250 to beat the Valk. The 70s are giving up 1/3 of their total mass to the 95s. The wind, even a light wind, is going to play hell on them. Actual BCs will be interesting t see.
 

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I was just going on reports of the 90 SMKs being used with success in 1000 yard matches from 1:8 twist barrels with MV of 3100fps.
I have become a believer in having amble twist. Copper bullets expand more with faster twist and longer bullets will have a higher BCs. The Berger 130 VLD doesn’t achieve its full BC in a 6.8mm 1:11 twist, it takes 1:10. Regarding the 90 SMK and .22-250, this bullet in a 1:8 twist launched at 3000+ fps will be stable and reach 1000 yards but the bullet is not stable enough to achieve its advertised BC. I would expect a 95 SMK would need a 6.5 twist at a minimum.
 

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If a PRS wanted to shoot 95 SMKs with more velocity than the Valkyrie, one could use a custom builder to manufacture a 1:6.5 twist barrel with a .22-250 reamer and a custom freebore and throat for the 95 SMK.

The Valkyrie is design to maximize performance in an AR platform. Would a Valkyrie bolt-action perform that much better than a custom/blueprinted AR? I'm keeping track of shots fired on my 22" Melonite Valkyrie barrel but I don't expect to wear it out anytime soon.
 

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Discussion Starter #18
I'm curious if the barrel life is going to be that much more than a typical 22-250? 1800-2000 is normal for the 22-250. I wonder if the 224 Vcan hold it together to 3600-4000?
 

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I have a melonite barrel and am expecting at least 5,000 maybe more.
 

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Discussion Starter #20
If 5000 can be expected from the Valkyrie then barrel life alone makes it viable to compete with the 22-250.
 
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