BlackHills 175g velocity not consistant

rickp

rickp

Sergeant
Full Member
Minuteman
Feb 24, 2008
453
2
Miami, Florida
www.threatsolutionsgroup.com
#1
I was out at the 1000y range yesterday and I chronoed my BH 175gr and the new Hornady 178gr round.

The BlackHills had quite a difference in velocities.
Here's a string 2574, 2599, 2603, 2601, 2570, 2579, 2593, 2570

This seems all over the place to me. Planing on calling BH tomorrow to see what they have to say.

How does one not get vertical stringing with this?

What's your take on this?

BTW the hornady ammo runs HOT, i got velocities in the 2800's at times.

R.
 
#4
Re: BlackHills 175g velocity not consistant

What do you expect to tell them on the phone???your loads suck??

Run the numbers..I get your average is 2586fps and standard deviation as 13... actually really good for a factory match ammo.
Zedieker said in his reloading book to keep reloads at 12 or less for standard deviation...your 13 is right there.

If your getting verticle stringing then your gun just doesnt like the round which is fine or you cant shoot

Is the HOrnady the 178grSuperformace ammo? if so it is gonnna be alot hotter. and they seem to group really well out of the guns I have seen


 
#5
Re: BlackHills 175g velocity not consistant

NO I'm not going to tell them their load suck, because they dont.
I will ask questions and get their take on it.

30fps differnece as is the case with some of those is excesive to me.

I would expect no more then maybe 10fps.

I need to educate myself with some of this to be honest. Hence my call. Not to bitch!!!
 
#7
Re: BlackHills 175g velocity not consistant

ITS FACTORY AMMO...not reloads...go reloads if you want less than 10 SD. What kind of gun is it?
 
#8
Re: BlackHills 175g velocity not consistant

I have chrono'd various factory rounds from several different manufacturers. I routinely obtain standard deviations in the 25-50 fps range, on occasion a little higher. This is through a gas piston gun, so cycling/gas port issues may have something to do with how large the #'s are (as compared to a bolt gun, which ought to be a little more consistent). If you're using a semi-auto with the gas system turned on (cycling), if anything, your #'s are better than I would have expected. If it was a bolt gun, you're right where you should be with factory ammo. I seriously doubt you will ever see anything better than what you showed using factory ammo.
 
#9
Re: BlackHills 175g velocity not consistant

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Rickp</div><div class="ubbcode-body">30fps differnece as is the case with some of those is excesive to me.

</div></div>

30fps ES from factory match ammo is actually pretty good. There was a time a few years back BH was up near the 90-100fps mark in spreads.

My match handloads are in the 20fps ES area.

As mentioned if you want super low numbers handload but I wouldn't spend toins of time and components chasing the single digit ES numbers.

The Hornady ammo is the Superformance. With a 26" barrel we are getting around 2830fps. It was made that way.
 
#10
Re: BlackHills 175g velocity not consistant

The most recent lot of BH I tested ran 2588fps to 2635fps in an 24" AI, with a 10-shot average of 2609fps, ES 47 and SD 13.

It's not as inconsistent as BH was for a while, but FGMM remains the standard.

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Rickp</div><div class="ubbcode-body">BTW the hornady ammo runs HOT, i got velocities in the 2800's at times.</div></div>I still can't find a decent lot of Superformance: Low 2700's or 2850+, with vertical stringing.
 
#11
Re: BlackHills 175g velocity not consistant

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Rickp</div><div class="ubbcode-body">The BlackHills had quite a difference in velocities.
Here's a string 2574, 2599, 2603, 2601, 2570, 2579, 2593, 2570

This seems all over the place to me. Planing on calling BH tomorrow to see what they have to say. </div></div>

Stop shooting over a chronograph and start shooting at targets.

Use the chrony to get a velocity for your ballistic calculations, then put it away and shoot.

BHA 175 match worked just fine while I was wringing out the Vortex Razor.

As mentioned, if you want super-low ES, then handload and weight each charge on the most accurate scale you can get. I shoot factory ammo when I want to spend more time shooting than with load development.
 
#13
Re: BlackHills 175g velocity not consistant

I've had some good results with less common factory loads:

NRA 155 SMK:

1) 2688.0 9.4
2) 2682.0 3.4
3) 2660.0 -18.6
4) 2655.0 -23.6
5) 2691.0 12.4
6) 2681.0 2.4
7) 2693.0 14.4

High: 2693.0
Low: 2655.0
E.S.: 38.0
Ave.: 2678.6
S.D.: 14.0
95%: ±15.1

HPS 155 SMK:

1) 2689.0 -16.4
2) 2688.0 -17.4
3) 2715.0 9.6
4) 2713.0 7.6
5) 2708.0 2.6
6) 2703.0 -2.4
7) 2699.0 -6.4
8) 2702.0 -3.4
9) 2720.0 14.6
10) 2717.0 11.6

High: 2720.0
Low: 2688.0
E.S.: 32.0
Ave.: 2705.4
S.D.: 10.7
95%: ±8.4

same ammo, second string later in the day:

1) 2713.0 -3.7
2) 2694.0 -22.7
3) 2715.0 -1.7
4) 2717.0 0.3
5) 2722.0 5.3
6) 2729.0 12.3
7) 2733.0 16.3
8) 2721.0 4.3
9) 2713.0 -3.7
10) 2700.0 -16.7
11) 2734.0 17.3
12) 2720.0 3.3
13) 2711.0 -5.7
14) 2725.0 8.3
15) 2703.0 -13.7

High: 2734.0
Low: 2694.0
E.S.: 40.0
Ave.: 2716.7
S.D.: 11.2
95%: ±6.6

HPS 175 SMK:

1) 2563.0 2.0
2) 2540.0 -21.0
3) 2570.0 9.0
4) 2559.0 -2.0
5) 2552.0 -9.0
6) 2563.0 2.0
7) 2567.0 6.0
8) 2553.0 -8.0
9) 2563.0 2.0
10) 2580.0 19.0

High: 2580.0
Low: 2540.0
E.S.: 40.0
Ave.: 2561.0
S.D.: 10.4
95%: ±8.3
 
#14
Re: BlackHills 175g velocity not consistant

Thank guys for the info. Well I guess that's about right then.

For those asking some questions, I'm using a CED M2 chrono set at about 10 feet from my AI AW with a suppressor on it.

The reason I chronoed the ammo was for the ballistic program.

I knew the Hornady ran hot but I wasn't expecting it to run around the 2800fps mark. I need to shoot it some more before having an educated opinion on it.

Again, thanks guys.

R.
 
#15
Re: BlackHills 175g velocity not consistant

Looks to me like your biggest spread is 31 fps. And youre griping about THAT out of factory ammo?

You better buy a reloader.

And sell your tac stuff and become a benchrest shooter.

Send me all your crappy BH ammo.
 
#16
Re: BlackHills 175g velocity not consistant

With our best match ammo we typically see 20fps spread- who cares? My personal best with a real rifle in a real match is 2.1 cm ( .83") at 300m (328 yards) for 5 shots. And no, that didn't win. Two other folk also using Norma Diamond line ammo beat me.
 
#17
Re: BlackHills 175g velocity not consistant

What is the accuracy / resolution of the Chrono your using?IIRC, some are +/- 2%.

What about lighting, humidity, temp, etc? Litz has something to say about these factors in his book.

Barrel condition?

It could be a factor affecting the results.....good luck!
 
#18
Re: BlackHills 175g velocity not consistant

I never worried about velocities in the past except to know it for the software. Other than that there's no point in really worrying about it IMO.

I just didn't know what was considered SD or excessive deviation, hence my post and question.

Anyway, again thanks for the replies guys.

R.
 
You must log in or register to reply here.

Similar threads

T
300 PRC
Replies
145
Views
32K
rustyinbend
rustyinbend
Top Bottom
Back
Home
Forums
Merch
Alerts