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-   -   Chronographed 17 HMR (https://www.rimfirecentral.com/forums/showthread.php?t=1151277)

plumas 02-16-2019 09:37 AM

Chronographed 17 HMR
From a 22" T-Bolt barrel...True velocities were higher than stated on the box!
To the nearest 5fps. I suppose factory numbers are from a shorter barrel?

CCI V-Max 17gr 2725 (Box says– 2550)
A17 17gr 2750 (Box – 2650)
Winchester HV 17gr 2645 (Box – 2550)
Hornady NTX (no lead) 15.5gr 2655 (no printed velocity on box)
CCI TNT Green (no lead) 16gr 2650 (no printed velocity on box)

Are there other ammo results out there?

B23 02-16-2019 12:34 PM

I've run a good amount of 17 HMR across my Magnetospeed chronograph and the velocities were allllllllllllllllllllll over the map. It's not uncommon to have an ES of 125-150+ fps.

As I've said many times before, having chronographed a fair amount of this stuff, it's amazing these things actually shoot as well as they do, considering the extreme velocity spreads this stuff has.

The manufacturers must think since most people aren't shooting much over 100yds and some well under that even, it's acceptable to have such a huge ES in the crap ammo they produce. Just think what these things would be capable of if they, consistently, could produce ammo with a ES of around 25fps. But then they'd probably want about $25+ for a box of ammo. :rolleyes:

plumas 02-16-2019 01:16 PM

Yes, I'll add that these velocities were an average of 10 shots and the variation from hi to low was at least 25fps and at most 75fps. Averages are all you can use when sighting in and running trajectory charts but it is disconcerting to see that spread.

Since the HMR can't be reloaded you get what 'they' offer in way of ammo. My best accuracy so far has been with the CCI hp, not the V-Max.

Smoothtrigger 02-16-2019 02:02 PM

The majority of .17hmr shooters have found that CCI TNT using the Speer Hollow-Point Boat-Tail bullet, and its clones have given the best accuracy.

I have no chrono info on the round, but I do have a ton of great targets.:)


plumas 02-16-2019 07:11 PM

That's the one...didn't know it was a Speer bullet...I like that.

Problem though starts in July in my 'smarter than me' state of Ca, choosing a lead-free bullet.
That drops the weight to 15.5 or 16 gr and I have not done accuracy testing on these....anyone?

jaia 02-16-2019 07:48 PM

My current hobby is 50 shots with rimfire at 200 yards across a chronograph.

Results are categorized by cartridge type and listed by brand.

Handy for information requests like yours.


Look at the 17 hmr section at lower portion of page

rjferber 02-16-2019 08:31 PM

My testing with CZ 453 & 455 Varmint 20.5" barrels usually produced significantly higher average velocity in just about all brands produced by CCI. I also used a Magnetospeed chronograph for my testing. I do not have any of the Winchester produced 17 HMR products so cannot comment on them. CCI A17 is the worst showing velocity spreads near 400 fps. Note the number of split case necks in each group as well. :eek:

As others stated - the Federal V-Shok TNT 17 gr seemed to produce the most consistent results in my CZ's & Steyr Zephyr II at this time, however it's a small sample size of only 250 rounds. I have shot 1,500 rounds of the other CCI manufactured ammo ( CCI & Hornady ) over the past 8 years.

1st - Round of Testing - 07-23-18

Group 1 # of Shots 50 Hornady Express VMax 17 gr @ 2550
Min 2391 Max 2656
Avg 2591 Std Dev 51 Split Cases ( 4 )
ES 265

Group 2 # of Shots: 20 Hornady XTP 20 gr @2375
Min 2418 Max 2537
Avg 2484 Std Dev 69 Split Cases ( 2 )
ES 119

Group 3 # of Shots: 50 CCI A17 Varmint 17 gr @2650
Min 2554 Max 2904
Avg 2774 Std Dev 88 Split Cases ( 16 )
ES 350

Group 4 # of Shots: 50 CCI Gamepoint 20 gr @ 2375
Min 2314 Max 2575
Avg 2505 Std Dev 44.5 Split Cases ( 1 )
ES 261

2nd - Round of Testing - 08-13-18

Group 1 # of Shots 25 Hornady Express VMax - 17 Gr @ 2550
Min 2529 Max 2787 Lot - C03P07
Avg 2616 Std Dev 62.6 Number of Split Cases ( 2 )
ES 258

Group 2 # of Shots 25 Hornady 17 HMR XTP - 20 Gr @ 2375
Min 2387 Max 2547 Lot - M02P20
Avg 2433 Std Dev 30.9 Number of Split Cases ( 2 )
ES 160

Group 3 # of Shots 50 CCI A17 - 17 Gr @ 2650
Min 2498 Max 2890 Lot - ? (Last 50 of 200 Round Box)
Avg 2756 Std Dev 87.9 Number of Split Cases ( 18 )
ES 392

Group 4 # of Shots 25 Federal V-Shok TNT HP - 17 Gr @ 2550
Min 2575 Max 2653 Lot - J14X23
Avg 2604 Std Dev 20.1 Number of Split Cases ( 0 )
ES 78

I like the 17 HMR rifles I have, but CCI's quality of most 17 HMR ammo is flat pathetic - just look at the Extreme Spreads within a group of 25 or 50 rounds. I will shoot up all the CCI & Hornady ammo I have on hand and use the Federal V-Shok TNT HP 17 gr going forward for any hunting requirements.

As always - Your Mileage May Vary.

Smoothtrigger 02-16-2019 08:59 PM

See post #4. "CCI TNT using the Speer Hollow-Point BoatTail bullet, and its clones have given the best accuracy."

One of those clones is the Federal TNT 17gr.
It's' made by CCI, and is the fact same round except for its tip color.
Feel free to pick up CCI TNT when available.
It's also sold as Remington .17gr TNT

However remember that just like Match .22lr ammo, the lot number and how it shoots in you rifle is still in play.


jaia 02-16-2019 09:06 PM

Federal, Hornady, Remington and CCI 17hmr all made on the same machines using CCI components.
Only differences in the brands are the labels, tip colors and headstamps.
Browning and Winchester 17hmr come from the Winchester machines.
Quality varies box by box as it comes off the assembly line.
What produces sub-moa at 100 yards today may spit 2 inch plus groups at 50 yards from the next box.
That is due to CCI and Winchester's minimal quality control.
Good enough for varminting, not for precision work. :(

plumas 02-17-2019 08:03 AM

These last few posts have helped me understand that it is not all me when groups open up here and there during a multi-box range day. Have not ever tracked lot #'s as a strategy to figure into group and chrono velocity before...just never thought of it.
In my ignorance I would have expected tighter controls off the factory line. Trying to de-mystify why one group is 3/4" and another is 2" with no external changes other than using a different box of the same ammo has been frustrating.

I suppose with the powder amounts involved even a 1/10 of a grain shift from one lot to another can be a significant % effecting velocity.

Excellent info on brand name vs actual manufacturer...another thing I did not know.
And all that chrono work...I feel I have enough info to build all the traj charts I'll ever need for any of my rimfires.

Have not shot the Federal, I'll look for that next.

I guess the strategy will be to check lot # on the boxes and buy enough of the same thing to control what I can to produce a bit more consistent group and sight-in results. Ya just hope 'your' lot will be a good one. Is there a better way to do it?

Thanks to all.

idahoron 03-16-2019 08:51 AM

I chronographed my CZ 17HMR yesterday and thought something was wrong. I was shooting 5 round groups and I did 4 groups. The average for them all was 2575. I took my air rifle to confirm that the speed was correct and as far as I know it was. I was using a Ohler 35.
Th box reads 2375 and I was wondering what was going on. After seeing the 50-200 test I see I am right in the ball park.
Thank you jaia for the hard work that went into making that available.

Smoothtrigger 03-16-2019 12:21 PM

For what it's worth, I've shot over 22,000 rounds of 17hmr over the last 9 years, and have never had a single spit case.
Never found one in a box, and never after it's been shot.

I only shot one box of Winchester, and they would barley chamber in my Anschutz's, and were hard to extract. Really complete crap.
Makes me wonder how tight some rifles chambers are.
Rifles are a Volquartesn Fusion semi-auto, a pair of Anschutz 1717's, and a Anschutz 1727F.


geographynerd48 03-22-2019 01:04 AM

What were the environmental conditions? The speed listed on the box is for 59 degrees. Also this doesnt mean 59 and ammo sitting in the car or in direct sun. As far as i know it means the ammo is 59 degrees too. Might be interesting to use a laser thermometer on the ammo just to see how that changes things.

Sent from my Nokia 6.1 using Tapatalk

tbates66 03-22-2019 10:54 AM

So the gist of all these posts is that measured speed is typically higher than the speed written on the box. OK. Does anyone know if this affects accuracy?

jaia 03-22-2019 12:37 PM

Just like any projectile, time of flight differences cause vertical spread.
Use of a ballistic calculator can produce a table that will display the variations in poi.
A larger problem is cartridge defects that cause unpredictable strays.
Variations in bullet shape and weight along with canted bullet seating
can cause very wild trajectories. There are no high quality 17 hmr cartridges,
only those made by CCI and Winchester.

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