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< 16ga. Ammunition & Reloading ~ need help with chronograph results |
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Posted:
Tue Apr 11, 2017 3:19 pm
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Joined: 26 Apr 2010
Posts: 3177
Location: NCWa
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Under checking for other variables, Do you have access to a different chronograph? |
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Posted:
Tue Apr 11, 2017 4:11 pm
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Joined: 30 Sep 2015
Posts: 640
Location: NEW SALISBURY INDIANA
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wellshooter wrote: |
Now ypu know that 6' of distance is worth 45 fps. Other than that ????
But I have to agree with you I couldn't match up with Hogdon data when I was working up my 2 1/2" 7/8 oz load with Universal. I just kept dropping the powder charge 1/2 grain at a time and retesting until I got in the range of velocity I wanted. I also shot a few factory Herters to check my chrono and bumped the charge up and down until I was pretty durn sure my data was consistently repeatable.
I suspect most of the loads on the Hogdon site are extrapolations from tested loads. Just don't know which load was tested.
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yep, I just loaded some 7gr, 7.5gr and 8 grain, going to keep lowering it until I get just under 1200fps |
_________________ 16ga 3-Win 37
16ga Ithaca 37 1946
16ga Western Auto Revelation
16ga Browning A-5 1929
16ga Marlin 90 1939
16ga browning citori lightning grade 3 2003
16ga Francisque Darne 1920 |
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Posted:
Tue Apr 11, 2017 4:35 pm
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Member
Joined: 27 Dec 2010
Posts: 387
Location: Spokane, WA
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Kennedy,
Did you mean to say 17, 17.5 and 18 grains?
If you are truly loading with only 7, 7.5 and 8 grains of powder, you will most likely not get a sufficient powder burn and pressure to make a usable load.
I'd make double sure my scale is calibrated and load up ten rounds with each different bottle of powder and take notes. Maybe try buying another sleeve of Win primers and shoot more over the chronograph.
I've had a published load with Unique that came back from testing quite a bit higher in pressure and faster velocity from what Alliant shows in their data. I never did nail down the cause of that issue. So I just moved on to other loads.
Lon |
_________________ 16 ga. Browning Citori White Lightning 28"
16 ga. Browning Citori White Lightning, 28"
www.lonlauber.com |
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Posted:
Tue Apr 11, 2017 5:34 pm
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Joined: 08 Feb 2009
Posts: 1310
Location: Western WA
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What is your crimp? A Hardin crimp or overshot wad can generate spurious chrono data. |
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Posted:
Tue Apr 11, 2017 5:41 pm
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Joined: 30 Sep 2015
Posts: 640
Location: NEW SALISBURY INDIANA
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oops, yes 17, 17.5 and 18, normal crimp |
_________________ 16ga 3-Win 37
16ga Ithaca 37 1946
16ga Western Auto Revelation
16ga Browning A-5 1929
16ga Marlin 90 1939
16ga browning citori lightning grade 3 2003
16ga Francisque Darne 1920 |
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Posted:
Tue Apr 11, 2017 6:26 pm
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Joined: 03 Feb 2014
Posts: 325
Location: West Texas
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My experience with the Universal 7/8 oz loads was that velocity decreased approximately 50 fps per 0.5 grain reduction, give or take 15-20 fps
I'll be curious to see what you get. |
_________________ 16 - The only "True" gauge
16 ga. Citori White Lightning
3- 16 ga. Remington M 31's
16 ga. Ithaca M 37 Featherlight |
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Posted:
Wed Apr 12, 2017 2:49 am
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Joined: 15 Dec 2005
Posts: 287
Location: missouri
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wellshooter wrote: |
Now ypu know that 6' of distance is worth 45 fps. Other than that ????
But I have to agree with you I couldn't match up with Hogdon data when I was working up my 2 1/2" 7/8 oz load with Universal. I just kept dropping the powder charge 1/2 grain at a time and retesting until I got in the range of velocity I wanted. I also shot a few factory Herters to check my chrono and bumped the charge up and down until I was pretty durn sure my data was consistently repeatable.
I suspect most of the loads on the Hogdon site are extrapolations from tested loads. Just don't know which load was tested.
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What a lot of people don't realize is the same warnings that apply to rifle/pistol powders also apply to shotgun powders, powder lots can vary by as much as 10% from listed recipes. It's never been fully expressed as a concern for some reason, probably because the powder companies don't believe 10% variance will make that much of a difference with shotgun loads.
You do the math and add 10% to listed velocities for the 18.5 grain Universal load and it brings you in right under 1300 fps around 1281 fps.
Loading a lot of STEEL powder I see variances as much as +/- 15% from listed recipes sometimes , so it's nothing that surprises me. |
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Posted:
Wed Apr 12, 2017 7:18 am
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Member
Joined: 16 Nov 2006
Posts: 1338
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Last edited by mike campbell on Fri Jul 26, 2019 11:03 am; edited 1 time in total |
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Posted:
Wed Apr 12, 2017 12:11 pm
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Joined: 30 Sep 2015
Posts: 640
Location: NEW SALISBURY INDIANA
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test results today, average of 2 shots
factory 1225
18 gr 1250
17.5 1225
17 1197
so I am going install a bushing that gives me close from 17 to 17.5gr, load a box and take it to the trap range and see what happens. BTW, the bore was clean, no residue. |
_________________ 16ga 3-Win 37
16ga Ithaca 37 1946
16ga Western Auto Revelation
16ga Browning A-5 1929
16ga Marlin 90 1939
16ga browning citori lightning grade 3 2003
16ga Francisque Darne 1920 |
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Posted:
Thu Apr 13, 2017 2:04 am
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Joined: 15 Dec 2005
Posts: 287
Location: missouri
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kennedy756 wrote: |
test results today, average of 2 shots
factory 1225
18 gr 1250
17.5 1225
17 1197
so I am going install a bushing that gives me close from 17 to 17.5gr, load a box and take it to the trap range and see what happens. BTW, the bore was clean, no residue.
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Around an 8% reduction in powder charge, to get you where you wanted to be. No matter what the powder companies claim sometimes you have to adjust. |
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Posted:
Thu Apr 13, 2017 8:32 pm
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Member
Joined: 08 Aug 2011
Posts: 1946
Location: Central CT
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I know that we all have chronographs that are perfect.......but they aren't.
There are a lot of variables here the main one being the chronograph and the fact that you have no way of knowing what the actual velocity is as you arent using ammo with a known velocity to setup the chronograph.
Without some sort of reference ammo everything you are doing is a guess and you are adjusting powder charges. That doesn't make a lot of sense. |
_________________ Mark |
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Posted:
Fri Apr 14, 2017 2:04 am
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Joined: 15 Dec 2005
Posts: 287
Location: missouri
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Dogchaser37 wrote: |
I know that we all have chronographs that are perfect.......but they aren't.
There are a lot of variables here the main one being the chronograph and the fact that you have no way of knowing what the actual velocity is as you arent using ammo with a known velocity to setup the chronograph.
Without some sort of reference ammo everything you are doing is a guess and you are adjusting powder charges. That doesn't make a lot of sense.
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I agree home/hobby type chronos are not always 100% accurate.
All powders however are made through only a few different processes and there's only a few companies that actually make powder for reloading. If the 10% off rule applies to pistol powders which are in may cases also used for shotgun shells , then it would make sense it would apply to shotgun loads also. Don't you think?? |
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Posted:
Fri Apr 14, 2017 3:14 am
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Member
Joined: 08 Aug 2011
Posts: 1946
Location: Central CT
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This 10% rule is imaginary.
I have never seen any statement from any powder company claiming any tolerance for their canister powders.
10% is huge, I would like to know the source.
I have to be honest, that I have not seen powders change performance without some change to the data. Steel was changed some years ago, but the data also was changed, as an example.
If your data is correct it means that the loads I just put together and shot with one of the latest lots of Universal powder are now producing close to 1600 FPS. No way is that the case.
However when I get a chance I will reshoot this stuff using Universal for velocity and post the results. I do have the original test sheet from Tom Armbrust and I will post that also.
I will do the same with 700-X. |
_________________ Mark |
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Posted:
Fri Apr 14, 2017 4:27 am
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Joined: 30 Sep 2015
Posts: 640
Location: NEW SALISBURY INDIANA
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loaded up a box using 17.4 grs, vel measured 1232 both test shots(factory tested at 1211(1200 on box) and went to the range. I hit less with the 17.4 gr box then with the 18.5 measured at 1338. I think the slower shot made my timing off a little and missed a few more then normal. otherwise it shot good, lighter recoil, clean barrel and did produce some dusted targets. |
_________________ 16ga 3-Win 37
16ga Ithaca 37 1946
16ga Western Auto Revelation
16ga Browning A-5 1929
16ga Marlin 90 1939
16ga browning citori lightning grade 3 2003
16ga Francisque Darne 1920 |
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Posted:
Sat Apr 15, 2017 6:02 am
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Joined: 15 Dec 2005
Posts: 287
Location: missouri
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Dogchaser37 wrote: |
This 10% rule is imaginary.
I have never seen any statement from any powder company claiming any tolerance for their canister powders.
10% is huge, I would like to know the source.
I have to be honest, that I have not seen powders change performance without some change to the data. Steel was changed some years ago, but the data also was changed, as an example.
If your data is correct it means that the loads I just put together and shot with one of the latest lots of Universal powder are now producing close to 1600 FPS. No way is that the case.
However when I get a chance I will reshoot this stuff using Universal for velocity and post the results. I do have the original test sheet from Tom Armbrust and I will post that also.
I will do the same with 700-X.
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I suppose these warning from different powder companies are imaginary also. You can see they are saying there is variation from lot to lot and why they say to start with minimum powder charges for rifle/pistol loads.
Playing the game of thinking you know more than the companies that make the components we use is a bit on the foolish side
From Alliant manual
The powder charge weights listed in our data
tables are maximum. For rifle and pistol loads,
the maximum powder charge should be reduced
by 10% to establish a minimum or starting
powder charge. The exceptions are those powder
charges designated “DNR” (Do Not Reduce).
From Accurate/Ramshot
Always begin loading at the minimum “Start Load”
• Increase in 2% increments towards the Maximum Load
• Watch for signs of excessive pressure
• Never exceed the Maximum Load
From Vihtavouri
Start loading with the starting load according to the
loading data. If there is no indication of the starting load, use
15 % lower charge than the listed maximum load. Increase
the charge using small steps watching for overpressure signs
from the primer and the case head at each step. If you
detect overpressures immediately stop shooting and
reduce the charge. Immediately disassemble the defective
cartridges. NEVER EXCEED THE MAXIMUM LOADS!
n Check visually the powder level in the cases so you are |
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