HuntingNut
HuntingNut
   Login or Register
HomeCommunity ForumsPhoto AlbumsRegister
     
 

User Info

Welcome Anonymous


Membership:
Latest: patrad69
New Today: 0
New Yesterday: 0
Overall: 13133

People Online:
Members: 0
Visitors: 146
BOT: 1
Total: 147
Who Is Where:
 Visitors:
01: Forums
02: Photo Albums
03: Statistics
04: Home
05: Forums
06: Home
07: Forums
08: Forums
09: Your Account
10: Forums
11: Statistics
12: Forums
13: Forums
14: Home
15: Forums
16: Photo Albums
17: Forums
18: Photo Albums
19: Photo Albums
20: Home
21: Forums
22: Forums
23: Forums
24: Home
25: Forums
26: Home
27: Forums
28: Your Account
29: Photo Albums
30: Home
31: Home
32: Forums
33: Forums
34: Home
35: Forums
36: Forums
37: Photo Albums
38: Forums
39: Forums
40: Photo Albums
41: Your Account
42: Home
43: Forums
44: Forums
45: Forums
46: Forums
47: Statistics
48: Forums
49: Photo Albums
50: News
51: Home
52: Photo Albums
53: Forums
54: Home
55: Home
56: Forums
57: Forums
58: Forums
59: Photo Albums
60: Forums
61: Photo Albums
62: Photo Albums
63: Forums
64: Forums
65: Home
66: Forums
67: Home
68: Forums
69: Home
70: Home
71: Photo Albums
72: Forums
73: Forums
74: Forums
75: Forums
76: Forums
77: Home
78: Forums
79: Your Account
80: Forums
81: Forums
82: Photo Albums
83: Forums
84: Home
85: Photo Albums
86: Home
87: Forums
88: Forums
89: Home
90: Forums
91: Forums
92: Forums
93: Home
94: Photo Albums
95: Home
96: Forums
97: Your Account
98: Home
99: Home
100: Home
101: Forums
102: Forums
103: Forums
104: Forums
105: Forums
106: Home
107: Home
108: Home
109: Forums
110: Your Account
111: Photo Albums
112: Forums
113: Forums
114: Forums
115: Forums
116: Forums
117: Photo Albums
118: Your Account
119: Your Account
120: Forums
121: Forums
122: Forums
123: Forums
124: Forums
125: Forums
126: Forums
127: Forums
128: Forums
129: Forums
130: Home
131: Photo Albums
132: Forums
133: Forums
134: Home
135: Home
136: Forums
137: Home
138: News
139: Forums
140: Forums
141: Home
142: Your Account
143: Forums
144: Forums
145: Home
146: Your Account
  BOT:
01: Home

Staff Online:

No staff members are online!
 

Coppermine Stats
Photo Albums
 Albums: 308
 Pictures: 2452
  · Views: 825082
  · Votes: 1316
  · Comments: 86
 

Strange Velocity
Discussion regarding the reloading of ammunition and tuning of loads for accuracy
Go to page Previous  1, 2
Post new topic   Reply to topic   Printer Friendly Page    Forum Index » Reloading Ammunition

View previous topic :: View next topic  
Author Message
shootist
Member
Member


Joined: Dec 30, 2005
Posts: 73
Location: Lackawaxen,PA

PostPosted: Tue Jun 13, 2006 5:52 pm    Post subject: Re: Strange Velocity Reply with quote

Hi Squirrelbait....I think PaulS has a handle on it...watch your [b]crimping.
Take a close look. Check flaring and the residual crimp.


Regards,

Shootist
Back to top
View user's profile
kbis
Super Member
Super Member


Joined: Apr 05, 2005
Posts: 312
Location: East, Texas

PostPosted: Tue Jun 13, 2006 11:01 pm    Post subject: Re: Strange Velocity Reply with quote

I agree that the condition of the barrel will have some affect, but to clean the barrel after every shot seems a little extreme. The 44 shot 5 of 6 rounds with only a total of 16 FPS between all of them. Isn't that pretty close or should I expect to get 1 or 2 FPS difference with cleaning the barrel between shots ?

I just looked at the cases again and from looking at the pimers I could not tell you which one was hot or slow, they all look the same.

I am using a "Chrony Master" and I had the shades in place. I don't know how much good they did since the sun was over my shoulder and shining right on the lenses.

As far as point of impact on the target some of that may be my fault. Yes I am shooting at a target, but my main concern is not shooting the chronograph.

There were a few clouds that day, but they were high and fluffy. You could not tell when the sun went behind a cloud, I wish they were dark so we could get some rain and break this hot spell.

I weigh each charge and will add or delete until I get a 0 on the scales. My scales are mechanical but old, but are supposed to be accurate to 1/10 of a grain. They were made for Lyman by Ohaus and still have the Gemco (if you remember them Smile ) price tag of $20.99

I don't remember if any brass was trimed with the 44, but it is a straight wall case like the 357 and they don't tend to grow like the bottle neck cases do. I do remember removing brass when I trimed the cases on the 30/30, but did not measure them as this has never been a problem in the past.

I sure appreciate all the inputs, When I get off these weird hours at work I will load up some more and try it along with a some factory loads to see what happens.
Back to top
View user's profile
guncollector
Member
Member


Joined: Apr 25, 2006
Posts: 68
Location: Houston, Texas

PostPosted: Wed Jun 14, 2006 5:19 pm    Post subject: Re: Strange Velocity Reply with quote

Extreme spread of 16 fps is very good even with a 4 shot sample. You could introduce more error than that if you cleaned after every shot and left slightly varying amounts of cleaning fluid in the barrel. I'm sure you've noticed that the first shot after a cleaning is usually a bit slower than following shots. That's why it is called a fouling shot.

Flattened primers are a indication of increasing pressure but, as Bushie points out, not necessarily overpressure. You can see this yourself if you load some moderate loads and some max loads and look at the primers. The higher pressure, max loads will typically flatten the primers more than a moderate load.

Perhaps a better high pressure indication is an extractor mark on the base of the cartridge. This is where the cartridge is shoved back against the extractor at greater than typical force. It looks like a shiny spot.

_________________
If the Government doesn't trust us with our guns, why should we trust them with theirs?
Back to top
View user's profile
kbis
Super Member
Super Member


Joined: Apr 05, 2005
Posts: 312
Location: East, Texas

PostPosted: Wed Jun 14, 2006 10:53 pm    Post subject: Re: Strange Velocity Reply with quote

Guncollector- I hate to ask dumb questions ( but seem to do so alot on this forum Smile ) but where will the "bright" spot be??

In a perfect world all the bullets will come out of the barrel at the same speed, but in the real world what range of spread is good? I seem to remember (old age is setting in Smile )reading some where that the SAMMI (or what ever the letters were) standard was 90 PFS.
Back to top
View user's profile
squirrelbait
Member
Member


Joined: Sep 23, 2005
Posts: 220
Location: Nottingham, NH

PostPosted: Thu Jun 15, 2006 5:41 am    Post subject: Re: Strange Velocity Reply with quote

Pauls, you raise an interesting thought.......not to get off topic but I have been wondering how my faster "varmit" loads in my 243 shoot lower impact from same point of aim at 100yds as my "deer" loads. Is this the answer? Varmit loads= 4000fps, deer loads= 2900fps.
Always confused and looking for answers!
Back to top
View user's profile
Bushmaster
Super Member
Super Member


Joined: Jun 12, 2005
Posts: 11395
Location: Ava, Missouri

PostPosted: Thu Jun 15, 2006 5:47 am    Post subject: Re: Strange Velocity Reply with quote

Squirrelbait...Pauls has it. Due to barrel recoil and recoil muzzle rise the slower bullet gets to the muzzle during that rise. Whereas the faster bullet gets to the muzzle sooner, hence less muzzle rise.

_________________
I have one nerve left and yer standin' on it...

DEMOCRACY Two wolves and one sheep voting on what to have for lunch...
LIBERTY A well armed sheep contesting the outcome of the vote...
Back to top
View user's profile
guncollector
Member
Member


Joined: Apr 25, 2006
Posts: 68
Location: Houston, Texas

PostPosted: Fri Jun 16, 2006 11:50 am    Post subject: Re: Strange Velocity Reply with quote

kbis -

You asked where the bright spot will be - a picture is worth a thousand words so go to

stevespages.com/table3.html and select "diagnosing problems" under the case section.

Steve's website is a treasure trove of information on reloading if you haven't found it before.

WRT "a good range of spread" I think the way to look at it is to find the load that gives you the lowest extreme spread. In one rifle, it might be 10 fps and in another it might be 50 fps. Consistent velocity is a key component of repeatable accuracy but not of accuracy in and of itself so you also have to find an accurate load.
Back to top
View user's profile
PaulS
Super Member
Super Member


Joined: Feb 18, 2006
Posts: 4330
Location: South-Eastern Washington - the State

PostPosted: Sat Jun 17, 2006 1:14 am    Post subject: Re: Strange Velocity Reply with quote

I never discover anything about velocity, extreme spread or Standard deviation until after I have selected and fine tuned my load.
I find the most consistantly accurate load and then run forty rounds over the chronograph to find out about all the "good stuff".
I load first and foremost for accuracy - so I find the one that hits the smallest spce on the target most often, under the widest range of conditions and then I find out how fast it goes, the standard and mean average deviation and the extreme spread. Then I test it in the fackler box for penetration and expansion. I compare that to my data base for past performance of that bullet to find out what I can expect on game. I record everything because I am working on an terminal ballistics formula that will approximate what I am recording in real life in the fackler box and in game. I should be able to come up with a formula that will tell me how much penetration and expansion I can expect for a given bullet at a given velocity - and whether it will explode on impact with a hummingbirds tail feathers or expand 10% as it breaks through the shoulder of a bull elephant. Ok - a slight exageration but I should be able to put some math together to cover the results of what I prove in the box and link it to "real world" hits.

_________________
Paul
__________________
Speer, Lyman, Hodgdon, Sierra, and Hornady = reliable loading data
So and So's pages on the internet = NOT reliable loading data
Always check data against manuals
NEVER exceed maximum listed loads
Back to top
View user's profile Send e-mail
kbis
Super Member
Super Member


Joined: Apr 05, 2005
Posts: 312
Location: East, Texas

PostPosted: Sat Jun 17, 2006 2:02 pm    Post subject: Re: Strange Velocity Reply with quote

PaulS
I have a dumb question, what is a "fackler box" ?

Guncollector
Great link, thanks.
Back to top
View user's profile
st_albert
Member
Member


Joined: May 31, 2006
Posts: 38

PostPosted: Sat Jun 17, 2006 6:41 pm    Post subject: Re: Strange Velocity Reply with quote

I'm not PaulS, but a Fackler box is basically a wooden trough that holds a bunch of ziploc sandwich bags filled with water in a line, with an open end. You shoot through the open end, through the line of baggies, and note the distance the bullet penetrated through the water-filled bags, and the expansion of the bullet. It's a "poor man's" substitute for ballistic geletin. Correlations exist to let you estimate the penetration in ballistic geletin it would have gotten, given how far through the water it went.

As to the original problem, I would mostly suspect the chronograph in the absence of other obvious causes. I'd fire more than 5 rounds per test, and if there's an outlier, just throw it out. If there are several outliers, then maybe you've got a problem.

My general rule for outliers is to calculate the mean and S.D. without the suspected value. If the suspected outlier is more than 3 times the S.D. away from the mean, OR if you have a known reason that it could be bogus (e.g. you dropped the cartridge on its nose and set back the bullet, or the primer showed definite high pressure signs and the others didn't), then throw the outlier out.

Just my $0.02,

Albert
Back to top
View user's profile
PaulS
Super Member
Super Member


Joined: Feb 18, 2006
Posts: 4330
Location: South-Eastern Washington - the State

PostPosted: Sat Jun 17, 2006 11:41 pm    Post subject: Re: Strange Velocity Reply with quote

Albert is right on with his description - Mine holds 48 one gallon bags of salene solution (sea water - salt water) It is enough denser than fresh water that bullets behave better than in the plain water.

I don't like "throwing out" fliers on targets or on the chronograph. Sometimes you might get erronious readings but if they are enough of a problem that you need to start throwing them from your calculations you need to change your equipment or fix the loading problem.

In this case I think your problem is the chronograph and the conditions you are using it.
I always use 15 feet from the muzzle to the midpoint between the screens. At that range you will rarely have any interference from gases modifying your readings. With you chrony try testing on overcast days - those days with gray skies and no direct sunlight or shadows.
If that is not possible then use filters that prevent direct sunlight from hitting the screens - it may take a fabricated cover over the entire chronograph plus a few feet in the direction of the sun. You need to eliminate the interference if you want accurate readings.

_________________
Paul
__________________
Speer, Lyman, Hodgdon, Sierra, and Hornady = reliable loading data
So and So's pages on the internet = NOT reliable loading data
Always check data against manuals
NEVER exceed maximum listed loads
Back to top
View user's profile Send e-mail
Display posts from previous:   
Post new topic   Reply to topic   Printer Friendly Page    Forum Index » Reloading Ammunition
Page 2 of 2
All times are GMT - 7 Hours
Go to page Previous  1, 2



Jump to:  


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum


Valid CSS! Valid HTML 4.01!
Click to check if this page is realy HTML 4.01 compliant for speed :)

All logos and trademarks in this site are property of HuntingNut.com.
The comments are property of their posters, all the rest © 2011 by HuntingNut.com
Interactive software released under GNU GPL, Code Credits, Privacy Policy

.: Upgraded to DragonFly 9.2 by *Dizfunkshunal* :.