Ammo preference

[Loke]

I recently acquired a CZ 455 Varmint in 22 LR. I know that every rifle is a rule unto itself, but it would be nice to know what ammo has the best chance for the best accuracy. Subsonic, standard, high velocity, and Hyper, what gives the best accuracy? and in each category.

[Model 52]

I don't have a 455, I have a CZ 453 American and a CZ 453 Varmint.

The 455 Varmint barrel is 20.5" and cylindrical while the 453 Varmint barrel is 22.5" with a tapered heavy barrel profile, but that should not make much difference on ammo preferences.

I shoot my 453s primarily at steel plates from 100-250 yards, with the majority of the shooting occurring at around 200 yards.  With mid range cost match ammo like SK Match or SK Standard Plus I get 1 MOA accuracy from the CZ 453 American and 1.25 MOA accuracy from the CZ 453 Varmint.   Both rounds produce around 1060 fps at those barrel lengths.


With high quality high velocity ammo the accuracy will drops off by at least .5 MOA or so, and at along range I prefer to crank in extra elevation and deal with greater drop in order to take advantage of the greater accuracy of the standard velocity and match rounds. 





 

[jollyscotsman]

I know that here in the UK,sub Sonics are generally accepted as the most accurate,most match shooters ,and small pest controllers will shoot subs for good reason,I'm led to believe that your supersonic round will become unstable when dropping into the transonic region of velocity,and accuracy falls of.I've tried all the hot lr ounds and found this to be true,plus the subs are a helluva lot quieter with a suppresor,which everyone hunting in the UK is allowed,not to sure if you can use suppresor,s in your part of the world mind you.

[chfields]

Good to know..I didn't know that...We can get suppressors here its just a major PITA......

[jollyscotsman]

A suppresor has It's own "slot" in UK,and is regarded as a firearm,which you have to apply for and have listed on your firearms certificate,along with the rifles you have been grantedbefore you can be sold one,,,I :know,crazy

[chfields]

Its crazy here to...fill out a mountain of paperwork send them a $200 "tax" and wait 6-12 months......

[jollyscotsman]

Copied this info from another forum about this,explains it better than I ever could!,,,, When the velocity of a rifle bullet fired at supersonic muzzle velocity approaches the speed of sound it enters the transonic region. In the transonic region, an important thing that happens to most bullets, is that the centre of pressure (CP) shifts forward as the bullet decelerates. That CP shift affects the (dynamic) stability of the bullet. If the bullet is not well stabilized(a perfect spiral football throw), it can not remain pointing forward through the transonic region (the bullets starts to exhibit an unwanted coneing motion(wobbly football throw) that, if not dampened out, can eventually end in uncontrollable tumbling along the length axis). However, even if the bullet has sufficient stability (static and dynamic) to be able to fly through the transonic region and remain pointing forward, it is still affected. The erratic and sudden CP shift and (temporary) decrease of dynamic stability can cause significant dispersion (and hence significant accuracy decay), even if the bullet’s flight becomes well behaved again when it enters the subsonic region. This makes accurately predicting the ballistic behaviour of bullets in the transonic region very hard. Because of this, marksmen normally restrict themselves to engaging targets within the supersonic range of the bullet used.

[Angryvikingman]

Federal Match 40gr is the best stuff you can get locally. There is some really well made german stuff that will blow federal match out of the water, but its $10 for 50 rounds the one place I've found it.