Buffalo Bore .357 Magnum 180gr LFN-GC 6" chronograph with some others

[Intercooler]

   The new GP100 functioned awesome as expected. The extra 2" helped with the balance more from what I could see and felt. I'm scrunching the numbers now but from memory I thought the results would have been much better than the 4".



I know The Shadow doesn't have the BB and I will put it in the next batch. How about the others in the next post?

[Intercooler]

  My normal control is the American Eagle 158gr JSP. I did these beginning and end plus they were my main practice/sighting round.

American Eagle 158gr JSP 1303, 1292, 1286, 1272, 1329, 1295, 1312, 1282, 1293. Average = 1296 FPS/ 589 LBS. Out of the 4" results were 1319 FPS/ 610 LBS.
Lapua 158gr JSP 1289, 1303, 1321, 1301, 1327, 1317. Average = 1309.66 FPS/ 602 LBS. Out of the 4" results were 1330 FPS/ 621 LBS.
Underwood 125gr Montana Gold HP reload 1635, 1588, 1565, 1647, 1606, 1580, 1624, 1591, 1592. Average = 1603.11 FPS/ 713 LBS. Out of the 4" results were 1546 FPS/ 664 LBS. Finally the added length shows something!!
PMC 150gr Starfire HP 1140, 1114. Average = 1127 FPS/ 423 LBS. Never tested in the 4".
Buffalo Bore 180gr LFN-GC (Rated 1400 FPS) 1398, 1376, 1388. Average = 1387.33 FPS/ 769 LBS. Out of the 4" results were 1375 FPS/ 756 LBS. Not a huge increase in the 6" but something!
American Eagle 158gr JSP 1326, 1300, 1304. Average = 1310 FPS/ 602 LBS.

Thoughts, comments?

[The_Shadow]

The numbers look good even though there isn't a great deal of difference from 4" to 6".
It would be nice to see what BB is using behind those 180's, maybe if I have the same powder on hand I can whip up a few with the RCBS 180 grain Silhouette Gas Checked if they occupy the same amount of casing capacity, The long tip of the SIL places the weight outside in most instances...The Cylinder should be the same length between the 4" & 6" Rugers...


I'll have to send you some more of the RCBS 180 Sil w/gc to see if you can reach the 1320 fps I was averaging from the S&W Mod19 6", you saw this from the Ruger 4" GP100 @ 1237, 1234. Average = 1235.5 FPS/ 610 LBS.

[Intercooler]

  It's kind of like we see in the 10mm where the lighter bullets get up in the longer 6" barrel. Kind of weird the heavy bullets seem to do their thing even in the 4" pipe.

[Intercooler]

Here is the data for .357 Magnum:

https://docs.google.com/spreadsheet/ccc?key=0Ak5OC6bPsjO8dHRYQjg2VzRjWEpUVlhXbjN0ZVMybFE#gid=3

Click the tabs at the bottom for the different weights.