CCI quiet velocity vs barrel length -chrony results

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ricksplace

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Not exactly a representative sample, but here are some interesting data.
Date: Today 10:00 am Temp 11.6 C sunny.
Muzzle to chrony distance 3 feet

The 22s I own I have kept over the last 40+ years of shooting. All of them will shoot around 1/2" at 50 meters with the kind of ammo the rifle likes. Every one of them has had a target crown installed, and a trigger job. Note they are all bolt guns, and not a short barrel in the bunch. All the barrels were dirty at the time of chronographing. I thought I'd include three different guns in the 24" barrel length to see if different guns made as much difference as barrel length.

Winchester 131 20.7" barrel
Springfield 84c 24" barrel
Norinco jw15 24" barrel
Cooey 60 24" barrel
Mossberg 146b 26" barrel
Cooey 75 27" barrel
Rem 513T 28" barrel

win s84 nrc c60 146 c75 513
783 751 777 633 713 699 794
783 740 766 647 704 699 672
780 741 756 643 724 707 723
759 739 741 665 728 699 711
771 737 730 657 718 709 705

Hardly a statistically valid sample, but the data still tell me a few things.

1. My Remington 513T which is the most accurate rifle in my stable, doesn't like CCI quiets.
2. The Cooey Model 60 is a slow rifle with these rounds. Strange. Can't explain it. Don't care.
3. No wonder the single shot cooey 75 is laser beam accurate up to 25 meters with this ammo.
4. I don't think we have to worry about sticking a bullet in the barrel with CCI quiets.
5. The gun seems to be more of a determining factor rather than barrel length as far as velocity and accuracy is concerned.
6. What the chronograph doesn't show is the noise level. The Winchester with the shorter barrel is quite a bit louder than the 24" barrel rifles. The longer the barrel, the quieter the report. The 27 and 28" barrels are a lot quieter than a kids bb gun.

Damn -when I post it, the columns don't line up. Sorry. Fixed it best I could.
 
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ricksplace said:
2. The Cooey Model 60 is a slow rifle with these rounds. Strange. Can't explain it. Don't care.

5. The gun seems to be more of a determining factor rather than barrel length as far as velocity and accuracy is concerned.
Click to expand...

Thanks for this info. I'd bet that your Cooey has a relatively tight bore, or maybe just a tight spot, resulting in greater friction. If you want to get all precise, you could slug your bores to see which is tight and which is loose. I'd bet you'd see a relationship there...
 
I've never bothered to chrony anything with my cooey 60, usually it's my savage that I use to warm up with before I shoot over mine. Next time I'll take the 60 up too and see if my results mirror yours just for kicks.

Yeah, try to line up those columns again! I sat there for a minute trying to decipher them before I scrolled down and read the next comment lol!
 
Thanks for posting your results, I have a current love affair with short barrels on my 10/22s but the short barrel pretty much requires hearing protection.

We have an old Savage single shot bolt gun with a 26" barrel that is a delight to shoot because it is so quiet.

What a person needs to do next is rent some equipment from an audio place and get some real decibel values on various barrel length and ammo options. I bet it would be enlightening to know, not only the decibel values, but how those values change depending on position.
 
your powder is mostly burned up at 16" after that the bullet is starting to coast, a lot less gas release out of the longer barrel than shorter barrel, hence less noise. All bores have differing levels of lead build up which accounts for the differing velocities out of same length barrels, (differing bore diameters)

with the quiets its likely the powder is burned up around the 11-13 inch mark. target ammo is typically burned up at 16"s
 
The lower noise from the longer barrel is due to the lower muzzle pressure that results, as well as farther distance from the ear which makes it seem less noisy.

The powder in a 22 RF is all "burned up" within about an inch of the boltface.
 
Tried some in a Ruger Mark III with a 5.5 " barrel and some would not make 700 fps
One of the BR50 guys tried some on the ARA target and while aiming at one target the impact was two targets low so at 50 yards it 4.4 inches low.
This was a rifle sighted in for standard velocity target.
 
I ran some over the chrony back when I had a savage fvsr and speeds were all over the map from 580- 710 fps. No consistency at all in that gun. They do a bit better in my cil but not a whole lot
 
Since i have a 513T was wondering? Some of my ammo advertises a MV of 1050 fps, so rather close to sonic which IIRC is at 1100. Thinking that i might get some of this ammo to break sound....then decel under...creating buffeting both times it crosses sound...and leading to inaccuracy.

Gun is scary accurate, and any small misses i have always attributed to me.......wondering if that 28" barrel is the issue...or a issue at all as it is a awesome shooter.
 
dizzy said:
your powder is mostly burned up at 16" after that the bullet is starting to coast, a lot less gas release out of the longer barrel than shorter barrel, hence less noise. All bores have differing levels of lead build up which accounts for the differing velocities out of same length barrels, (differing bore diameters)

with the quiets its likely the powder is burned up around the 11-13 inch mark. target ammo is typically burned up at 16"s
Click to expand...

There is a barrel length test done using different barrel length CZ 452 rifles. Seems like the 22.5 or carbine 20.7" barrel got the best velocities.
The cartridges were:
CB Longs = CB
RWS Subsonic Hollow Points = SSHP
Wolf Match Target = Standard Velocity or SV
American Eagle Solids = Lead High Velocity or LHV
CCI Mini Mag Solids = Plated High Velocity or PHV
CCI Stingers = Hyper Velocity or HypVel

-----CB SSHP SV --LHV -PHV HypVel
28.6 652 968 1037 1206 1188 1660

24.8 676 997 1062 1219 1217 1660

22.5 653 998 1069 1229 1213 1708

20.7 701 957 1062 1224 1190 1661

16.5 685 949 1057 1205 1208 1666
Click to expand...

Source
http://thefiringline.com/forums/showthread.php?t=352255
 
hometownhero said:
I ran some over the chrony back when I had a savage fvsr and speeds were all over the map from 580- 710 fps. No consistency at all
Click to expand...

I must have had some from the same lot that you had!! I don't have a chrony but I could feel the difference when I pulled the trigger, and then saw that it printed 2" lower then the first 2 I shot almost touching. had the same problem with a bunch of other brands of cheaper .22 SV ammo too.

Now I'm going to start weighing all my .22 rounds for just to see and sticking them in different '5 shot' lines.
 
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