CCI Subsonic. . . is not

[Tryin']

After I had my CZ barrel cut to 17.5", CCI subs go supersonic on me. RWS does not. Most target ammo does not. The air temp was 21*F at the last test, giving a barrier at 1074.xx FPS. CCI says SSHP ammo is loaded at 1050 FPS, which I should not reach until 0*F.

Is CCI loaded hot?

I'm shooting a CZ 452 Varmint, regarded to have a tight bore; will bore size influence velocity?

 

[VUPDblue]

When you are talking about a threshold differential of under 100fps due to ambient temperature and humidity, it may not be the ammo's fault. If you want ammo that is subsonic even in the extreme cold, use the slowest ammo you can find. 1050 is too close to the supersonic threshold mark IMHO to be reliably calculated and relied upon in the extreme cold.

 

[Tryin']

I was thinking along those lines. . . 20 FPS is not a large margin. . . Perhaps why SSHP cycles my semis more reliably. Hotter load imparts more energy to the bolt, but still soft enough to be sub-sonic afterwards.

My CB longs are the slowest I have, but I cringe when I shoot them through my suppressor. Probably no reason to, but. . .

 

[VUPDblue]

I've always had good luck with *shudder* Remington subsonics always being reliably quiet.

 

[Tryin']

Indeed. But the shotgun patterning board at the range is always in use.

And while my suppressor is quieter dirty. . . Not that dirty.

Thanks for the info regarding velocity!

 

[U.S. Patriot]

I've always had good luck with *shudder* Remington subsonics always being reliably quiet.

The Remington sub-sonics feed 100% reliably through the 597 I used to own. My Buckmark also feeds them 100% reliably.

 

[dom1104]

might want to get a shorter barrel. they stay subsonic for me in my 10.5 ar upper.

 

[snapping turtle]

I read a couple of web sights that had Fred from bullberry explaining velocity and barrel lenght a couple of times. I can find it now maybe in fred archives somewhere.
He would cut down barrels and recrown and repeat over and over.

In his barrels i think 16 inches was the sweet spot in 22 lr, highest vel of them all. You just cut off 3 or 4 inches of what i believe fred discribed as drag. IN a 24 inch cz barrel they would most likely be sub rounds. And like mentioned a 10.5 inch barrel SBR would again not let the vel build up to it's max yet so the same load is sub at 10.5

Shorts cb's and cb caps and others are available but each has it's drawbacks, I take it you did the chop on a bolt action gun not an autoloader.

 

[snowman46919]

The Remington sub-sonics feed 100% reliably through the 597 I used to own. My Buckmark also feeds them 100% reliably.

My ruger mkII fed them flawlessly I had problems with failure to fire

 

[brotherbill3]

I read a couple of web sights that had Fred from bullberry explaining velocity and barrel lenght a couple of times. I can find it now maybe in fred archives somewhere.
He would cut down barrels and recrown and repeat over and over.

In his barrels i think 16 inches was the sweet spot in 22 lr, highest vel of them all. You just cut off 3 or 4 inches of what i believe fred discribed as drag. IN a 24 inch cz barrel they would most likely be sub rounds. And like mentioned a 10.5 inch barrel SBR would again not let the vel build up to it's max yet so the same load is sub at 10.5

Shorts cb's and cb caps and others are available but each has it's drawbacks, I take it you did the chop on a bolt action gun not an autoloader.

I'ver heard explanations about this (and as an engineer, it makes sense w/ the low powder charge in a .22 LR) ... hope you can find the article. I'd love to see it; it would be interesteing because I have 30 y.o. short (16 to 18") barreleed Marlin Semi. for me, I have no Chrono, but everything seemed be just as loud as the next, sub-sonics and High/Hyper velocities.

 

[combat45acp]

The Remington sub-sonics feed 100% reliably through the 597 I used to own. My Buckmark also feeds them 100% reliably.

I have had good luck with Remington subs also, everyone on the internet forums seems to bash them and I can't figure out why. They run the all my semi-pistols and rifles.

CCI Standard is "quieter" than CCI Subs, and they stay subsonic for me...go figure? The CCI Subs I bought I run through my 5" or less pistols because they cycle good. If you want to stick with CCI and stay Sub Sonic in your rifle, buy CCI standards.

 

[snapping turtle]

He is one from Freds sight it was just like this format but I can not find the 22 lr link maybe it is hidden

this one is for 204 ruger.
204 Ruger Velocities

 

[Tryin']

Thanks for the info, guys.

Dom, my CZ is already on the edge of looking "odd", another 7" off and it would definitely cross over.

Edit: I don't bash Remington for reliability as I have yet to find a round that won't cycle my bolt-action. . . They are just the dirtiest, second least accurate round for my primary rimfire; a CZ 452.

 

[Aszerigan]

I reload my subs to about 900fps, specifically for this reason. I recommend you test them out of a shorter barrel. I'm not saying its NOT the ammo, but I'm betting that ambient temperature isn't the only problem here.

 

[Glocker1986]

I have used Remington subsonics in both my 10/22's. In my opinion they are very dirty and inconsistent. I am looking to try some of the offerings from cci. When I find some I will post a report.

 

[CountryBoy19]

IMHO 20 FPS is not enough difference to keep you out of the transonic range. Look at the chart below and you will see why you need to be well below supersonic to keep the noise down.

100 fps would be more along the lines of what you should be looking for.

 

[Slow Hand]

I've got my Savage MKII cut to 18" and CCI Standard Velocity loads have always been subsonic fo rme. Groups fairly well; not as good as most Eley stuff, but easier to find and a bit cheaper. I went out last weekend to sight in my new scope and it was in the lower 20's and they stayed subsonic.

One point that has been covered a few times here and I"m indisagreement with, is a shorter barrel. I've read a few tests and with the small amount of powder in a .22, the bullet is actually slowing down by the time it's leaving the barrel. I think I read that the fastest barrel length for average .22's was around 13". That having been said, I shot some CCI SV's otu of my 13" barreled AC556 with a Ceiner (p'touie!) kit and they stayed quiet when ran through my OBII.

I have shot a few hundred of the Remington SubSonic HP's out of my 3 1/2" Ruger MKII with the can on it and they are noticable quieter than many other kinds of ammo. Have shot them through my Kel Tec SU-22 and they functioned 100% (until it got really dirty) and were all quiet in the 16" barrel. I do remeber trying some Remington target ammo (Eley primed) and it must have been right at the borderline because about 0% of them were supersonic.

If you are lookin for the ultimate quiet round out of a suppressed bolt action, try and find some Remington CeeBee's. They use a sectioned SWC-HP bullet. Very light loads and are nearly silent through the boltgun. I shot some into a bucket of sand and they expanded very nicely. Usually what I keep ready for pest control around the house. Only place I've seen them locally is at gander Mountaina nd I think they were like $10 a box of 100. Not cheap, but they are darned quiet!

Doug K

 

[8th SPS USAF]

CCI subsonic

I went to Class 3 Sales and tested Kent's Mite with Rem SS and CCI standard vel 22 ammo . The Rem was louder than the CCI SV. CCI
works my 10/22 16.5 " fine and my Sig 220 22 conv fine.