Why not HV ammo?

[Nocalphoenix]

I notice the love for the wolf 40 target and I finally picked up a couple boxes of the stuff. Accuracy at 50 was good, consisent .6" for five, 5 shot groups. My normal Winchester Power points and CCI minimags ran about .80" and some of the Aquila Interceptor (40gr at about 1400fps I think) was right at 1".

Then I went out to a 6" plate at 150yards with switching winds up to 10-12mph. Long story short the Aquila was the most consistent at that range and gave the highest hit percentage once I figured elevation holds for each ammo. The Aguila was using about 1/2 of the wind holds and the wolf was driving me nuts with horizontal misses that I attribute primarily to my inability to read the wind.

Why dont more people use the HV stuff for matches? I know at short range and small targets the more precise ammo would give higher scores but it seems the extra wind advantage of the HV would give an advantage for the matches pushing longer ranges on larger targets.

 

[paraman1]

Re: Why not HV ammo?

The problem with HV ammo is that when it goes Transonic (drops below the sound barrier) it tends to destabilize the bullet . The same thing happens with your centerfire rifles as well .

 

[donws2]

Re: Why not HV ammo?

There's also the problem of quality control. Most High speed 22 ammo has greater lot speed variance from lot to lot. There's no reason not to use higher speed ammo in the wind. I still use older UM1 for that reason. But I know the quality is there for the UM1. I just don't have the trust in the other mass produced high speed stuff.

 

[Nocalphoenix]

Re: Why not HV ammo?

Michael,
Im admittedly ignorant on the full ballistics of rimfires, at about what ranges does the standard or HV stuff go transonic?

I know it well and used to see my .308 groups double between 900 and 1000 yards when they went unstable.

 

[paraman1]

Re: Why not HV ammo?

The speed of sound is 1125 fps in dry air at 68 degrees fahrenheit . This changes when your atmospheric data changes . Many of the Bullet Drop Calculators will take this into account . The problem with HV ammo is that it generally starts out at 1250-1350 fps so it drops below the sound barrier fairly rapidly upon leaving the barrel . Try the JBM ballistics calculator online as I believe it has a column for when it goes transonic .

You also have to keep in mind that the goal with most .22 trainers is to get rounds downrange cheaper than your centerfire rifle while using the skillsets you want to keep sharp or improve on . If your practicing logging data , ranging targets , calculating bullet drop and windage , breathing , NPA , trigger control and the other myriad of skills that go into becoming a more proficient long range shooter your money ahead of the guys who aren't shooting at all . Obviously the more consistent the ammo is the easier many of these jobs become .

AS per the norm , YMMV , IMHO , Just my .02 , YADA YADA , BLAH BLAH . Good luck and have fun !