Sooty case head

[Scotch_egg]

Has anyone ever had a sooty case head?

6mm Creedmoor new Lapua brass
87gr Hornady V-Max
37-38gr Vihtavuori N150 as per the app.

 

[GregP42]

Is it in an AR style weapon? If so look at your gas rings maybe, especially if it is being shot suppressed.

 

[Scotch_egg]

Is it in an AR style weapon? If so look at your gas rings maybe, especially if it is being shot suppressed.

Bolt action

 

[vinniedelpino]

Has anyone ever had a sooty case head?

6mm Creedmoor new Lapua brass
87gr Hornady V-Max
37-38gr Vihtavuori N150 as per the app.

Is this from a bolt gun?

Were the 87's loaded super short?

 

[Scotch_egg]

Is this from a bolt gun?

Were the 87's loaded super short?

Loaded to mag length for Sako 85. I believe the same length as factory Hornady.

 

[vinniedelpino]

Loaded to mag length for Sako 85. I believe the same length as factory Hornady.

Any performance issues with the rifle? Is velocity consistent?

And is this the factory barrel?

 

[Scotch_egg]

Any performance issues with the rifle? Is velocity consistent?

And is this the factory barrel?

Fresh re-barrel. I didn’t check velocity.

 

[Cascade Hemi]

Very light load and the brass isn't sealing. 38gr charge weight is roughly 40Kpsi. Start at 40gr and work up.

 

[Rocketvapor]

Residual lube ?

 

[918v]

Very light load and the brass isn't sealing. 38gr charge weight is roughly 40Kpsi. Start at 40gr and work up.

+1

 

[Scotch_egg]

Residual lube ?

Only neck uniformed as it was new brass

 

[Scotch_egg]

Very light load and the brass isn't sealing. 38gr charge weight is roughly 40Kpsi. Start at 40gr and work up.

I used the load data from the Vihtavuori app

I might try higher load then.

 

[918v]

I used the load data from the Vihtavuori app

I might try higher load then.

The 87gr load on VV website is for a short COAL of 2.669”

Note the 90gr data. It’s for a longer COAL and it shows a higher charge weight.

 

[Scotch_egg]

The 87gr load on VV website is for a short COAL of 2.669”

Note the 90gr data. It’s for a longer COAL and it shows a higher charge weight.

That’s very interesting indeed.

Using this website a higher charge is safe.

P-Max internal ballistics

 

[Cascade Hemi]

That’s very interesting indeed.

Using this website a higher charge is safe.

P-Max internal ballistics

Even VV's starting load for the 90gr is low enough to be unsafe. 50K to 62K should be your working range.

Cartridge : 6 mm Creedmoor
Bullet : .243, 87, Hornady V-MAX 22440
Useable Case Capaci: 49.271 grain H2O = 3.199 cm³
Cartridge O.A.L. L6: 2.800 inch = 71.12 mm
Barrel Length : 20.0 inch = 508.0 mm
Powder : Vihtavuori N150 *C

Predicted data by increasing and decreasing the given charge,
incremented in steps of 1.0% of nominal charge.
CAUTION: Figures exceed maximum and minimum recommended loads !

Step Fill. Charge Vel. Energy Pmax Pmuz Prop.Burnt B_Time
% % Grains fps ft.lbs psi psi % ms

-10.0 84 36.00 2638 1344 37233 10974 97.4 1.224
-09.0 85 36.40 2666 1373 38343 11093 97.7 1.206
-08.0 86 36.80 2693 1401 39483 11209 98.1 1.189
-07.0 87 37.20 2721 1430 40655 11322 98.3 1.172
-06.0 88 37.60 2748 1459 41861 11431 98.6 1.156
-05.0 89 38.00 2776 1488 43100 11536 98.9 1.140
-04.0 90 38.40 2803 1518 44373 11636 99.1 1.124
-03.0 91 38.80 2830 1548 45682 11733 99.3 1.108
-02.0 91 39.20 2857 1577 47028 11826 99.5 1.093
-01.0 92 39.60 2885 1607 48412 11914 99.6 1.078
+00.0 93 40.00 2911 1638 49836 11998 99.7 1.063
+01.0 94 40.40 2938 1668 51299 12077 99.8 1.049
+02.0 95 40.80 2965 1699 52804 12152 99.9 1.034 ! Near Maximum !
+03.0 96 41.20 2992 1729 54352 12222 100.0 1.020 ! Near Maximum !
+04.0 97 41.60 3018 1760 55944 12287 100.0 1.006 ! Near Maximum !
+05.0 98 42.00 3045 1791 57581 12348 100.0 0.993 ! Near Maximum !

Results caused by ± 10% powder lot-to-lot burning rate variation using nominal charge
Data for burning rate increased by 10% relative to nominal value:
+Ba 93 40.00 3030 1773 58633 11658 100.0 0.986 ! Near Maximum !
Data for burning rate decreased by 10% relative to nominal value:
-Ba 93 40.00 2744 1455 41097 11851 95.7 1.163

 

[Scotch_egg]

Even VV's starting load for the 90gr is low enough to be unsafe. 50K to 62K should be your working range.

Cartridge : 6 mm Creedmoor
Bullet : .243, 87, Hornady V-MAX 22440
Useable Case Capaci: 49.271 grain H2O = 3.199 cm³
Cartridge O.A.L. L6: 2.800 inch = 71.12 mm
Barrel Length : 20.0 inch = 508.0 mm
Powder : Vihtavuori N150 *C

Predicted data by increasing and decreasing the given charge,
incremented in steps of 1.0% of nominal charge.
CAUTION: Figures exceed maximum and minimum recommended loads !

Step Fill. Charge Vel. Energy Pmax Pmuz Prop.Burnt B_Time
% % Grains fps ft.lbs psi psi % ms

-10.0 84 36.00 2638 1344 37233 10974 97.4 1.224
-09.0 85 36.40 2666 1373 38343 11093 97.7 1.206
-08.0 86 36.80 2693 1401 39483 11209 98.1 1.189
-07.0 87 37.20 2721 1430 40655 11322 98.3 1.172
-06.0 88 37.60 2748 1459 41861 11431 98.6 1.156
-05.0 89 38.00 2776 1488 43100 11536 98.9 1.140
-04.0 90 38.40 2803 1518 44373 11636 99.1 1.124
-03.0 91 38.80 2830 1548 45682 11733 99.3 1.108
-02.0 91 39.20 2857 1577 47028 11826 99.5 1.093
-01.0 92 39.60 2885 1607 48412 11914 99.6 1.078
+00.0 93 40.00 2911 1638 49836 11998 99.7 1.063
+01.0 94 40.40 2938 1668 51299 12077 99.8 1.049
+02.0 95 40.80 2965 1699 52804 12152 99.9 1.034 ! Near Maximum !
+03.0 96 41.20 2992 1729 54352 12222 100.0 1.020 ! Near Maximum !
+04.0 97 41.60 3018 1760 55944 12287 100.0 1.006 ! Near Maximum !
+05.0 98 42.00 3045 1791 57581 12348 100.0 0.993 ! Near Maximum !

Results caused by ± 10% powder lot-to-lot burning rate variation using nominal charge
Data for burning rate increased by 10% relative to nominal value:
+Ba 93 40.00 3030 1773 58633 11658 100.0 0.986 ! Near Maximum !
Data for burning rate decreased by 10% relative to nominal value:
-Ba 93 40.00 2744 1455 41097 11851 95.7 1.163

Even VV's starting load for the 90gr is low enough to be unsafe. 50K to 62K should be your working range.

Cartridge : 6 mm Creedmoor
Bullet : .243, 87, Hornady V-MAX 22440
Useable Case Capaci: 49.271 grain H2O = 3.199 cm³
Cartridge O.A.L. L6: 2.800 inch = 71.12 mm
Barrel Length : 20.0 inch = 508.0 mm
Powder : Vihtavuori N150 *C

Predicted data by increasing and decreasing the given charge,
incremented in steps of 1.0% of nominal charge.
CAUTION: Figures exceed maximum and minimum recommended loads !

Step Fill. Charge Vel. Energy Pmax Pmuz Prop.Burnt B_Time
% % Grains fps ft.lbs psi psi % ms

-10.0 84 36.00 2638 1344 37233 10974 97.4 1.224
-09.0 85 36.40 2666 1373 38343 11093 97.7 1.206
-08.0 86 36.80 2693 1401 39483 11209 98.1 1.189
-07.0 87 37.20 2721 1430 40655 11322 98.3 1.172
-06.0 88 37.60 2748 1459 41861 11431 98.6 1.156
-05.0 89 38.00 2776 1488 43100 11536 98.9 1.140
-04.0 90 38.40 2803 1518 44373 11636 99.1 1.124
-03.0 91 38.80 2830 1548 45682 11733 99.3 1.108
-02.0 91 39.20 2857 1577 47028 11826 99.5 1.093
-01.0 92 39.60 2885 1607 48412 11914 99.6 1.078
+00.0 93 40.00 2911 1638 49836 11998 99.7 1.063
+01.0 94 40.40 2938 1668 51299 12077 99.8 1.049
+02.0 95 40.80 2965 1699 52804 12152 99.9 1.034 ! Near Maximum !
+03.0 96 41.20 2992 1729 54352 12222 100.0 1.020 ! Near Maximum !
+04.0 97 41.60 3018 1760 55944 12287 100.0 1.006 ! Near Maximum !
+05.0 98 42.00 3045 1791 57581 12348 100.0 0.993 ! Near Maximum !

Results caused by ± 10% powder lot-to-lot burning rate variation using nominal charge
Data for burning rate increased by 10% relative to nominal value:
+Ba 93 40.00 3030 1773 58633 11658 100.0 0.986 ! Near Maximum !
Data for burning rate decreased by 10% relative to nominal value:
-Ba 93 40.00 2744 1455 41097 11851 95.7 1.163

I didn’t realise the pressures were so low. Those loads shouldn’t be on the viht website!

 

[straightshooter1]

Very light load and the brass isn't sealing. 38gr charge weight is roughly 40Kpsi. Start at 40gr and work up.

+1
38 gr of N150 is producing very low pressure and not sealing the chamber.