New Ruger K77/22-VHZ (22 Hornet) bolt action rifle.
New winchester cases.
CCI 500 small pistol primers.
Hornady 35 grain V-MAX.
Hodgdon's H110 powder.
COL 1.725"

I fired 50 shots with powder charged in 7 steps from 11.8 grs to 12.4 grs.
When I got home I checked the velocity stored in the chrony's memory.
I was shocked to see the average velocities were 100 to 130 fps faster than what the books (Hornady 7th, Hodgdon's 2010 Annual) say I should be getting.
This occurred at all charge weighs.

I examined the cases with a large magnifier and strong light and I can see a very slight bulge and a crack on the pressure ring on all the cases that hit 3160 fps and faster.

The crack is very faint I couldn't see it at the range while shooting.
Some cracks go 1/3 to all the way around the case.
Primers look fine their edges almost the same as the unfired cartridges.

I cut a couple of the worst looking case down their length, polished the edges on fine sand paper.
I could not see that the cracks had actually penetrated into the side of the case.
The cracks appear just as a faint scratch on the surface of the brass and there was no thinning of the brass to be seen on the inside of the cases.
I could not feel any crack or thinning on the other cases with a sharpen right angled hook probe.

The lighter 11.8 and 11.9 charge weighs made 3099 & 3138 fps and did not show any bulge or cracks.

Should I toss the cases or keep them for use with the lower pressure LIL'GUN powder?

I'm thinking I should reserve some cases fired with low pressure LIL"GUN and use these fire formed cases for use in the higher pressure H110 loads.
Maybe their will be less chance of the cases cracking and no bulges would occur if they were already a tighter fit (fire formed) to the chamber.

Naturally I will back off the powder charge weighs with H110.

running 100fps over the book isn't what I'd call excessive. No more so than another rifle might run 100fps under.
It sounds like you're running near the top end however but your signs sound okay. Smart lad to section a case for a look see. I'd look to my rifle to check if it's a incidental mark --rather than a crack--made by your rifle's chamber.

As Mr. Beeman suggests, if your not showing pressure signes on the primers, there is a good chance you have a bugaboo in your chamber. Mass produced rifles often have problems. Get someone with a borescope to look if you can. Higher velocity by itself shouldn't be a problem. Some guns just outperform others.

If the brass looked ok when you cut one open, that is another sign that the chamber has something causing the mark.

What kind of chronograph do you have. I had two chronys and both read about a 100fps faster then what i was really getting. Also check your bullet seating dept. Seating deep can raise pressure and increase velocity.

Lloyd S.

My chronograpth is a Shooting Chrony the Beta Master model.
It was set up about 12 feet from the rifle muzzle.

I'm not sure how one would be able to test the device to confirm its measurement accuracy.
Maybe I could shoot a 22 rimfire across it using high quality match target ammo that has a published velocity value and a reputation for being true to the published muzzle velocity.
I did shoot my Excaliber crossbow across it and I did get velocities consistant with what Excaliber published velocity spec are.

I checked each cartridge COL to verify it was on 1.723" the COL of the Hornady & Hodgdon's load recipe.
I also took Speer manual #14 advice and used small pistol primers which Speer found kept pressure down, hopefully it will also make the SD more stable in the Hornet.

I will try to see if there is any raised ridge like tool marks in side the chamber that could be embossing the cartridge case just above the solid head portion of the case head.

Winchester factory 45 grain ammo which is suppose to run 2690 fps according to Winchester shot 2628 fps out of my rifle.
These Winchester factory ammo also had the crack like mark on them, on most of the fired cases.

Too much coincidense. I don't know what the numeric probably is but the chance of you getting a box of ammo and each case has an insepid crack and your virgin brass having the same problem is just too astronomical.

If the rifle was mine,(I ain't reccomending this to no one)I'd find a suitable shotgun brush or pistol brush that would just fit the chamber. I'd put that in a length of cleaning rod. I'd then tease some 0000# steel wool into the bristles and put that in a drill motor. Using the drill, I'd run this contraption into and back out of the chamber. One time. Then I'd shoot a round and see if the mark on the brass has changed. (clean the chamber before shooting the round)
Other than that, if you can't get a good look into the chamber, I'd take it to a smith for a look see just for the peace of mind.

You have nothing to worry about. Remember you are not shooting your rifle with the same equipment nor under the same conditions as those that published the data. Here's a work up for you.

1. log your data and select the load you feel gives you the best accuracy, velocity etc.

2. Load a batch of 25 to 30 rounds and see if you are maintaining the same results you got when testing.

3. Load your data into your software program and get your "down range data" i.e. FPS, Energy, TOF (Time of flight), POI (Point of impact) and minutes of angle.

4. Load up another batch this time about 50 to 75 rounds and zero in where you want and work up your minute scale i.e. 100=zero 150= 1/2 minute 200=1 1/2 minutes etc.

5. Compare your computer data next to your actual data.

At this point you can "reverse calculate" and determine exactly what your velocity is. Well at least an exact average if such a thing exists? In any event, I don't go that far and simply chart my actual data for my load to use on my cheat sheet.

As far as your case cracks are concerned, it sounds like a head-space problem. You also sound like your going for the gusto with velocity. With that said you may want to back off your sizing die about 3/16 of an inch and work up your loads from start using .2 increments. Remember maximum velocities are less accurate than those of moderate velocity.