R.W.Dale
Member
I dont remember the exact thread but a few weeks ago a poster had posted his results using faster powders to get most of the velocity at half the charge of the usual standby "magnum" propellants.
Today I tested the same theory using two firearms and two powders.
Firearms used: S&W 60-18 5"bbl and a Uberti rolling block with a 22" barrel
Load details: Brass Norma, magtech SR primer, Montana Gold 158g JHP
The propellants were HS6 and H110/296 loaded to "MAX" loads/ 9.5g for HS6 and 16.0g for h110/296
HS6 22"bbl
1430
1451
1471
1456
1454
average 1452 FPS
h110/296 22"bbl
1775
1809
1788
1771
1803
average 1789 FPS
H110/296 advantage over HS6 in the Rifle 337 fps
HS6 5"revolver
1160
1143
1135
1142
1171
average 1150 FPS
h110/296 5"revolver
1213
1206
1247
1262
1244
average 1234 FPS
advantage h110/296 84FPS
Conclusion; it would appear as though for handguns there is little velocity gain to justify the added expense and blast of the "magnum" powders, but with longer barrels this narrow performance gap becomes a chasm. Its worth noting though that even though the performance increase is small the slower propellant still delivers top velocity in the short bbl.
also chronographed was Hornady's 140g Leverevolution factory loads. they averaged 1378 and 1845fps respectively
all readings taken at 10 feet, sunny day, temp 84
Today I tested the same theory using two firearms and two powders.
Firearms used: S&W 60-18 5"bbl and a Uberti rolling block with a 22" barrel
Load details: Brass Norma, magtech SR primer, Montana Gold 158g JHP
The propellants were HS6 and H110/296 loaded to "MAX" loads/ 9.5g for HS6 and 16.0g for h110/296
HS6 22"bbl
1430
1451
1471
1456
1454
average 1452 FPS
h110/296 22"bbl
1775
1809
1788
1771
1803
average 1789 FPS
H110/296 advantage over HS6 in the Rifle 337 fps
HS6 5"revolver
1160
1143
1135
1142
1171
average 1150 FPS
h110/296 5"revolver
1213
1206
1247
1262
1244
average 1234 FPS
advantage h110/296 84FPS
Conclusion; it would appear as though for handguns there is little velocity gain to justify the added expense and blast of the "magnum" powders, but with longer barrels this narrow performance gap becomes a chasm. Its worth noting though that even though the performance increase is small the slower propellant still delivers top velocity in the short bbl.
also chronographed was Hornady's 140g Leverevolution factory loads. they averaged 1378 and 1845fps respectively
all readings taken at 10 feet, sunny day, temp 84