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  #16  
Old 06-25-2016, 12:52 PM
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Quote:
Originally Posted by alum572 View Post
...most of mine averaged about 1.25" at 100 w 5 shot groups. That was about .25" or so better than most of my .22 mags.
Yes, I think your experiences with .17 HMR and .22 WMR mirror most others I've seen. And it surprises me, in that the .17 HMR is just the .22 WMR necked down. This reduces the expansion ratio. With most centerfire cartridges, better accuracy usually accompanies larger expansion ratios. Following this logic, with equal-quality bullets and care in cartridge assembly, the .22 WMR should exhibit better inherent accuracy. But it doesn't. I wonder whether it just comes down to (a) better-quality bullets in the .17 HMR and/or, perhaps, (b) more care in the construction of the other components and in the cartridge assembly with the .17 HMR.

And following the same logic a little further, we might expect very-slightly better accuracy from the .17 M2 than from the .17 HMR, although I haven't seen definitive evidence to support this.

Last edited by South_Pender; 06-25-2016 at 02:43 PM.
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  #17  
Old 06-25-2016, 09:07 PM
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My Annie 1717 will consistently do .5" groups at 100 yds IF the ammo is good. Way too much variation in 17HMR ammo.
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  #18  
Old 06-26-2016, 11:31 AM
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Ugghhhhhhhhhh!

Maybe we're having issues with what average, all day long, or consistently means.

The only reason I care is because of setting unrealistic expectations, especially for new shooters.

Smooth

Last edited by Smoothtrigger; 06-26-2016 at 12:08 PM.
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  #19  
Old 06-26-2016, 01:20 PM
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Quote:
Originally Posted by Smoothtrigger View Post
Ugghhhhhhhhhh!

Maybe we're having issues with what average, all day long, or consistently means.

The only reason I care is because of setting unrealistic expectations, especially for new shooters.

Smooth
Good point, Smooth. It would be pretty disappointing for a shooter--particularly a beginner--to be doing everything right, but shooting groups that are twice the size of what he's seeing other shooters reporting with the same equipment. Perspective is needed, along with some agreement regarding terms. It's probably expecting too much to ask that shooters adopt the NRA practice of 5 or 10 consecutive 5-shot groups as the basis of their accuracy reports; the intention, after all, isn't to make shooting a chore, so all reports should be welcome, I think.

In the interests of walking the talk, let me report a little more on the performance of my Anschutz 1727F .17 HMR. I'd reported earlier some groups shot at 50 yards with both the Hornady 17-gr. V-Max load and the CCI 17-gr. TNT load. With each of those two loads, I shot 4 consecutive 5-shot groups, obtaining an average group size of .34 for the V-Max load and .33 for the 4 groups shot with the CCI-TNT load. So, an average of .335 over the 8 groups shot at 50 yards. These were shot, in decent but not great conditions, with a 2.5-25X42 March scope mounted.

Last week, I shot at 100 yards with the same setup except that I substituted a 45X45 Leupold Competition scope for the March scope on the 1727F. Conditions were fairly good, around 60F, mixed sun and clouds, with light winds (maybe 4-5 mph), and I tried (not always successfully) to shoot in what seemed like calm periods. Most of my groups were shot with the Hornady 17-gr. V-Max load. Here are my results from 7 consecutive 5-shot groups shot with that load:

.70", .89", .70", .65", .78", .65", 1.03". The 7-group average is .77". When I superimposed the 7 targets on one another, all 35 shots went into 1.20".

One thing I usually do when averaging group sizes is to calculate what statisticians call a "trimmed mean." For this, you drop the largest and smallest group size and compute the mean on the remaining group sizes. This tends to produce a more stable average--one not disproportionately affected by unusually small or large groups. The trimmed mean for my 7 groups above (that is, the average of the 5 groups without the smallest and largest groups included) is .744.

Oddly, though--given my results at 50 yards--the 3, 100-yard 5-shot groups I shot with the CCI-TNT load were comparatively poor--an average over the 3 of 1.10". I ran out of time before I could do more extensive testing with the TNT load. I can't explain these results. The TNT rounds I fired were from the same lot number as those I shot--with much better results--at 50 yards.

Last edited by South_Pender; 06-26-2016 at 01:27 PM.
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  #20  
Old 06-26-2016, 01:55 PM
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I took delivery of a new Savage BTVS stainless .17 HMR a week ago and have been testing various ammunition both at 50 and 100 yards . I am used to an Anschutz MPR that shoots in the .200's off the bipod and the new Savage is a big change . Best ammo so far has been the 17gr CCI TNT hollow point . Shoots about .500 or so at 50 and about an 1" at 100 yards ( 5 shot groups off a bipod with a 15x scope ) . Everything else is crap . Typical is about 1.5" at 100 yards . No consistency at all . Significant velocity variations in the same box . I am going to work with a cheap X Ring barrel tuner to see if it will help any . Not complaining , just the Anschutz with good match ammo has spoiled me .
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  #21  
Old 06-27-2016, 07:01 PM
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Originally Posted by HondaVTEC View Post
I took delivery of a new Savage BTVS stainless .17 HMR a week ago and have been testing various ammunition both at 50 and 100 yards . I am used to an Anschutz MPR that shoots in the .200's off the bipod and the new Savage is a big change . Best ammo so far has been the 17gr CCI TNT hollow point . Shoots about .500 or so at 50 and about an 1" at 100 yards ( 5 shot groups off a bipod with a 15x scope ) . Everything else is crap . Typical is about 1.5" at 100 yards . No consistency at all . Significant velocity variations in the same box . I am going to work with a cheap X Ring barrel tuner to see if it will help any . Not complaining , just the Anschutz with good match ammo has spoiled me .
I tried the x ring on a ruger and it didn't do anything as far as I could tell. Different pressure on the first 3" of barrel is doing a lot more. Smooth I appreciate you keeping it real for us. Just frustrating for me cause if I can't expect 1" at 100 off a bench in good conditions then a hmr feels like a waste to me in the presuit of longer range squirrel hunting. Makes me
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  #22  
Old 06-27-2016, 07:20 PM
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The X Ring damper had a significant effect on my Anschutz MPR , but , it takes time and testing to get the location just right . My HMR shoots the CCI TNT quite well , but , no local dealer has it available so I will have to find a solution to make the other ammo shoot within the realm of reason . 1" groups at 100 yards is all I'm after . Like I said , the Savage is definitely not the Anschutz as far as accuracy goes .
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  #23  
Old 06-27-2016, 08:26 PM
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Quote:
Originally Posted by HondaVTEC View Post
The X Ring damper had a significant effect on my Anschutz MPR , but , it takes time and testing to get the location just right . My HMR shoots the CCI TNT quite well , but , no local dealer has it available so I will have to find a solution to make the other ammo shoot within the realm of reason . 1" groups at 100 yards is all I'm after . Like I said , the Savage is definitely not the Anschutz as far as accuracy goes .
You're Canadian, right? The place below has lots of CCI TNT if you don't mind buying online. I picked up a bunch that way from them recently.

http://www.bullseyelondon.com/ammuni...unition/17-hmr

What exactly is the "X ring dampener"?
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  #24  
Old 06-27-2016, 09:36 PM
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https://www.youtube.com/watch?v=Xq2G2MubmuE

The X Ring dampener is a rubber "donut" that sides on the barrel to tune barrel harmonics . Does it work ? Absolutely . But it takes a bit of time and testing to find the correct position .

I am in Atlantic Canada , Yes . I have no issue ordering online if that is the only choice but I do prefer to support the local dealers as much as possible .

Last edited by HondaVTEC; 06-27-2016 at 09:38 PM.
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  #25  
Old 06-28-2016, 08:14 AM
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My cz455 with a 8/32 Hawke scope and a less than 1lb trigger can consistanly shoot nickel sized groups at 100 ar the indoor range. This is off a wobbly table using a bipod and monopod setup. A bad group is an inch which happens about 30% of the time from a flyer or just a bad shot.

Before I adjusted the trigger the groups were consistanly 1 inch or slightly larger. The trigger is the biggest issue on any gun.
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  #26  
Old 06-28-2016, 09:06 AM
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I shot a 1/4 inch 3-round group once. According the the Internet, that means means it is. .25 MOA gun.

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  #27  
Old 06-28-2016, 10:29 AM
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Quote:
Originally Posted by HondaVTEC View Post
I took delivery of a new Savage BTVS stainless .17 HMR a week ago and have been testing various ammunition both at 50 and 100 yards . I am used to an Anschutz MPR that shoots in the .200's off the bipod and the new Savage is a big change . Best ammo so far has been the 17gr CCI TNT hollow point . Shoots about .500 or so at 50 and about an 1" at 100 yards ( 5 shot groups off a bipod with a 15x scope ) . Everything else is crap . Typical is about 1.5" at 100 yards . No consistency at all . Significant velocity variations in the same box . I am going to work with a cheap X Ring barrel tuner to see if it will help any . Not complaining , just the Anschutz with good match ammo has spoiled me .
I was having a problem with mine with the 2 action studs becoming loose. Tq them to 15 lb in as recommended with loc tite, this made a significant increase in accuracy and consistency.
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  #28  
Old 06-28-2016, 12:54 PM
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Actually , I took my 93/17 rifle apart last night and it did appear that the rear action screw was not right . So , that was fixed , I made a thicker bottom plate out of stainless ( the stock one was very thin and flimsy ) , torqued it all back together and went to the range with it today . A buddy shot one 5 shot group using my worst preforming ammo and it was a ragged hole at 50 yards . It never did that before with that ammo ! We were shooting at 200 yards and did not test another group . I will try it again on Friday . Hopefully our one group was not a fluke as it's been pretty unimpressive up to this point .
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  #29  
Old 06-28-2016, 02:25 PM
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I like hard numbers.
Which is why I record results for later perusal.

Here's 500 rounds of 17 hmr mv's

weight ...number...muzzle velocities
grains ...................feet per second

39.6..........3.....2723, 2704, 2677
39.7..........2.....2559, 2578
39.8..........3....2496, 2549, 2510
39.9..........4....2549, 2549, 2604, 2554
40.0..........37...Hi 2715, Lo 2478, Avg 2611
40.1..........11...Hi 2721, Lo 2645, avg 2687
40.2..........52...Hi 2715, Lo 2544, Avg 2606
40.3..........73...Hi 2732, Lo 2564, Avg 2647
40.4..........87...Hi 2737, Lo 2446, Avg 2651
40.5..........65...Hi 2737, Lo 2398, Avg 2660
40.6..........66...Hi 2737, Lo 2578, Avg 2678
40.7..........76...Hi 2732, Lo 2510, Avg 2623
40.8..........16....Hi 2721, Lo 2672, avg 2692
40.9..........4....2699, 2726, 2672, 2704
41.0..........1....2710

You can see the mv's jump all over the place.
The results on target reflected the vertical spread caused by the differing mv's.

Using that data, I did the math, based on time of flight,
and found that it is mathematically possible to hit a dime every time
at a distance of about 90 yards on a dead calm day.
That means the hole left from firing those 500 rounds at a single poa,
would be the diameter of a dime plus 0.17 inches, or about 0.88 inches, call it 1 moa.

Which doesn't do any good if you happen to get a box with canted bullets.
In that case there's no telling where the rounds will impact.
Yeah, been there, shot that brick, seen the horror.

Last edited by jaia; 06-28-2016 at 02:29 PM.
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  #30  
Old 06-28-2016, 03:02 PM
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Sounds about right. Shot these 3 targets as prep for my 100yd rimfire match in medium winds (3-5mph) swirling due to our baffle system.


Rifle was my Anschutz 1717D Lilja shooting CCI TNT off a Bulls Bag.
You can sneak in a good one if your only looking at one 5 shot group.
Both of the twenty shot groups if I had stopped and measured each five shot string would have given and average under and inch.
However they would not have averaged under .5 inches.

Smooth

Last edited by Smoothtrigger; 06-28-2016 at 04:44 PM.
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