[Dave2pa]

the hornady book i have does not have any data for this bullet ,i am using IMR 4831 powder,,, any data would be helpfull
270 Cal 130 gr SST these are the polymer tipped bullets

 

[WildBill]

Cartridge Name: 270 Winchester

Bullet Type = .277 130 GR SST HORNADY Bullet Weight = 130.0 grains
Bullet Diameter = 0.277 in Bullet Length = 1.240 in
Bullet BC = 0.46 Sectional Density = 0.242
Case Type = 270 Winchester Case Length = 2.540 in
Full Case Capacity = 67.063 grains water Est. Overall Cartridge Length = 3.350 in
Net Case Capacity = 60.523 grains water Bullet Seating Depth = 0.430 in
Rifle Type = Barrel Length = 22.0 in
Effective Barrel Length = 19.89 in Barrel/Case Volume Ratio = 5.9
Cartridge Temperature = 70.0 °F
__________________________________________________________________________________

Powder: H4831
Calculated Powder Charge = 49.4 grains
Load Density = 81.7%
Charge/Bullet Weight Ratio = 0.38
Estimated Muzzle Velocity = 2537 ft/sec
Estimated Chamber Pressure = 35868 CUP
Load Table


(%) (grains) Wt. Ratio (ft/sec) (CUP)
-------------------------------------------------------------------------------------
75 45.4 0.349 2331 30060 OK
80 48.4 0.372 2485 34416 OK
85 51.4 0.395 2639 38773 OK
<span style="font-weight: bold">90 54.5 0.419 2799 43274</span> OK
95 57.5 0.442 2953 47631 OK
100 60.5 0.465 3107 51987 High Pressure


Start at 54/55grs.

 

[Ghogs Nightmare]

From their new 9th Edition manual:
Starting load...49.5 (2600fps)
MAXIMUM load....56.1 (3100fps)
**IMR 4831**

 

[WildBill]

Sorry.....missed the IMR!

Cartridge Name:
__________________________________________________________________________________

Bullet Type = .277 130 GR SST HORNADY Bullet Weight = 130.0 grains
Bullet Diameter = 0.277 in Bullet Length = 1.240 in
Bullet BC = 0.46 Sectional Density = 0.242
Case Type = 270 Winchester Case Length = 2.540 in
Full Case Capacity = 67.063 grains water Est. Overall Cartridge Length = 3.350 in
Net Case Capacity = 60.523 grains water Bullet Seating Depth = 0.430 in
Rifle Type = Barrel Length = 22.0 in
Effective Barrel Length = 19.89 in Barrel/Case Volume Ratio = 5.9
Cartridge Temperature = 70.0 °F
__________________________________________________________________________________

Powder: IMR 4831
Calculated Powder Charge = 49.4 grains
Load Density = 81.7%
Charge/Bullet Weight Ratio = 0.38
Estimated Muzzle Velocity = 2737 ft/sec
Estimated Chamber Pressure = 41755 CUP
__________________________________________________________________________________

WARNING: For starting loads reduce calculated powder charge by at least 10%.


Load Table
-------------------------------------------------------------------------------------
Load Charge Charge- Muzzle Chamber
Density Weight to-Bullet Velocity Pressure Notes
(%) (grains) Wt. Ratio (ft/sec) (CUP)
-------------------------------------------------------------------------------------
75 45.4 0.349 2515 34993 OK
80 48.4 0.372 2682 40065 OK
85 51.4 0.395 2848 45136 OK
90 54.5 0.419 3020 50377 High Pressure
95 57.5 0.442 3186 55448 High Pressure
100 60.5 0.465 3352 60520 High Pressure