Thread: Subsonic 22lr going supersonic?

I got a hold of some CCI subs to try out as the killwell stuff I had been using was so gungy after only 20 rounds I would have to flick the cases out with a knife as they wouldnt extract.

The first shot out of the box was very loud, thats odd I thought. I tried 1 more and it was another loud crack. The next one was a bit quieter then they settled down. I then got a callout so went and sorted the job out and on the drive back I was thinking perhaps some oil was left in the barrel and it dieseled until it was clear.

I shot 100 rounds in 2 sessions and in my last 20 another 1 was a loud crack.

Overall I liked the CCI stuff and no extraction issues over the 100 rounds. Am I right in assuming I went a little heavy on the oil last time I put it away or could it be poor quality control from CCI which I find unlikely as it was the first 2 but then that third one has me puzzled.

Get the same with Lapua magazine tin @ smallbore. Very looooong barrel though

Mines 16" with a suppressor, do you think its just the ammuniton QC?

Too many variables to know really

Hot weather, ammo sitting in sun, high altitude, maybe something in the barrel like you said....

My target 22 does not have a supressor fwiw, but can still hear the difference between sub and super.

was it cci subs or cci standard most think its the same speed but standards are much faster than sub just on the verge of breaking the sound barrier so close that one on 3 or 4 dose most target ammo including laupa magazine above is standard not sub a true subsonic round should never break the sound barrier

Just went and pulled out the box of CCI I've been having supersonic shots from. Thought maybe they were standard velocity, but no they are subsonics. I've always assumed it's because I have a 25 inch barrel meaning the posted 1050 fps hovers closer to the sound barrier. But after hearing your experience I'm wondering since it's never been an issue before.

Had also entertained the idea of the first few shots being do to obstructions in the barrel from never cleaning the thing. But like yourself will experience a few shots with no problem then randomly have a crack.

one of the numbers on the side is A29U18, possibly a batch number I don't know.

Poor QC could be an issue, but still accurate in my rifle.

Originally Posted by rambo-6mmrem

was it cci subs or cci standard most think its the same speed but standards are much faster than sub just on the verge of breaking the sound barrier so close that one on 3 or 4 dose most target ammo including laupa magazine above is standard not sub a true subsonic round should never break the sound barrier

Definantly subs, I checked at the store then second guessed myself in the carpark then glanced at the box after the loud ones.

The most reliable .22 Subs are the Aussie made Winchester, Also the most pricey

Hmm odd I have put over 500 rounds of CCI Subs through my 10/22 with Suppressor and never heard any more than the action opening and closing. Fixed our bunny population explosion.
Must be a quality control thing !!

Originally Posted by rambo-6mmrem

was it cci subs or cci standard most think its the same speed but standards are much faster than sub just on the verge of breaking the sound barrier so close that one on 3 or 4 dose most target ammo including laupa magazine above is standard not sub a true subsonic round should never break the sound barrier

CCI rate their Standard Velocity round @ 1070 fps whilst their Sub-Sonics are 1050 fps - virtually the same. Speed of Sound is generally 1127 fps so they both should be well short of that. I use both CCI Subs and Standards for general plinking (use better stuff if I want better results on the day) and have fired off thousands of them and have never perceived any noise difference. The only downside with CCI shows up when shooting on paper - both Standards and Subs seem to put the odd shot out of the group which could be caused by a different velocity for that shot - maybe higher or lower. I also have chronographed a lot of different 22s and the CCIs were roughly as stated on their packets thru a standard length barrel.

Originally Posted by shooternz

The most reliable .22 Subs are the Aussie made Winchester, Also the most pricey

yep that's my hunting ammo I use a marlin 25n 16 inch barrel and a can yes its pricey I've payed as much as $15 a box for it from the farm supply's in the middle of nowhere as I run out and was going hunting that night but that's a good thing most farm supply's I've gone in that seems to be the ammo stocked so easy to get more if you run out
it kills real well way better than the cci subs

I use fed auto match target ammo (bulk box) for practice or plinking saves burning the Winchester

I see the killwell stuff is made by Winchester in Australia, is the stuff you guys rate different?

Its also 37.5gr and 1050fps which may also explain why I think the CCI is also generally slightly louder pushing a 40gr to 1050fps? I will have to load a mag up with most and do a test next weekend.

Originally Posted by JRW87

Its also 37.5gr and 1050fps which may also explain why I think the CCI is also generally slightly louder pushing a 40gr to 1050fps? I will have to load a mag up with most and do a test next weekend.

The Kilwell Whispers were 37.5gr but I think now they (ah Winchester) have changed the brew, and the packet colour, to 40gr subs. I am told they don't shoot as well as the old ones. I managed to pick up 2 bricks of the old ones as they shoot extremely well in my Marlin.

Ive dropped them on rabbits at what I estimate to be 100 metres rested on the deer mesh but I just cant deal with having to clean my rifle twice in one evenings shooting.