Hi all,
had some extra time (could not sleep at night) and started thinking, "why a hell do we need so powerful loads for 100m shooting & training"? All shooters are struggling to get some more FPS, but brass, gunsmithing and barrel life for sure are not cheap anymore...
So, first thing that came on my mind was "Optimal barrel time concept" (you can google it).
My barrel is 8.5" twist 4-groove 1.25" straight SS button rifled Lothar Walter, CIP min. chamber, finished length is 28".
Optimal barrel times for my barrel are:
1.) 0.94477 mS = 2211 FPS
2.) 1.0374 mS = 2420 FPS
3.) 1.1892 mS = 2774 FPS
4.) 1.2795 mS = 2985 FPS
5th and 6th are useless, with 120-130 grs pills unreachable...
My normal loads are 123 Scenars or 120 Bergers (both 10 thousands jammed, Berger shoots little better), using 35.6 grs of VV150 (for third node - 2.800 FPS) and 38,6 grs of same powder for fourth node (2.980 fps). Loads are in ones and low twos...
Using 123 naked Scenars and IMR Trailboss max. speed was approx. 1600 FPS (compressed load), so I started killing my head which powder to use... I wanted to fill at least 70% case capacity, so fast powders like RL15, VV140 were not at my list...pistol powders also not...than came on my mind that H4350 fills case nicely...
32.5 grs H4350 at 115 yards(123 Scenars, BR4s):
http://i1167.photobucket.com/albums/q623/stgw77/H4350reducedload4_zpsf300d59a.jpeg?t=1370439361
Velocity: 2406, 2406, 2406; AV=2406; ES=0;ES=0
33,0 grs H4350:
http://i1167.photobucket.com/albums/q623/stgw77/H4350reducedload3_zps345725c9.jpeg
Velocity: 2424, 2415, 2415; AV=1418; ES=9; SD=5
33,5 grs H4350:
http://i1167.photobucket.com/albums/q623/stgw77/H4350reducedload1_zps6adca08e.jpeg?t=1370439438
Velocity: 2455, 2469, 2478; AV=2467; ES=23; SD=11
Case was filled 80%+, and so far I am extremely happy with accuracy
I know that 3 rounds are not a lot, but looks promising so far...This reduced load has POI only 1"-1.5" lower than 2800 FPS load at 115 yards... rifle recoils nearly the same, no big difference. This will be my 100 m & training load, maybe I will shoot it at 300 m also...need to try that...No stability issues so far. It would be good to know how long my bbl would last with this load, reduced for 400-500 FPS (!!!), pressure should also be very lower also, brass should last long...
Please try to put numbers into QuickLoad and publish them. If you try this load (on your own risk of course), also please share your experince with us!!!
Best regards from Europe
had some extra time (could not sleep at night) and started thinking, "why a hell do we need so powerful loads for 100m shooting & training"? All shooters are struggling to get some more FPS, but brass, gunsmithing and barrel life for sure are not cheap anymore...
So, first thing that came on my mind was "Optimal barrel time concept" (you can google it).
My barrel is 8.5" twist 4-groove 1.25" straight SS button rifled Lothar Walter, CIP min. chamber, finished length is 28".
Optimal barrel times for my barrel are:
1.) 0.94477 mS = 2211 FPS
2.) 1.0374 mS = 2420 FPS
3.) 1.1892 mS = 2774 FPS
4.) 1.2795 mS = 2985 FPS
5th and 6th are useless, with 120-130 grs pills unreachable...
My normal loads are 123 Scenars or 120 Bergers (both 10 thousands jammed, Berger shoots little better), using 35.6 grs of VV150 (for third node - 2.800 FPS) and 38,6 grs of same powder for fourth node (2.980 fps). Loads are in ones and low twos...
Using 123 naked Scenars and IMR Trailboss max. speed was approx. 1600 FPS (compressed load), so I started killing my head which powder to use... I wanted to fill at least 70% case capacity, so fast powders like RL15, VV140 were not at my list...pistol powders also not...than came on my mind that H4350 fills case nicely...
32.5 grs H4350 at 115 yards(123 Scenars, BR4s):
http://i1167.photobucket.com/albums/q623/stgw77/H4350reducedload4_zpsf300d59a.jpeg?t=1370439361
Velocity: 2406, 2406, 2406; AV=2406; ES=0;ES=0
33,0 grs H4350:
http://i1167.photobucket.com/albums/q623/stgw77/H4350reducedload3_zps345725c9.jpeg
Velocity: 2424, 2415, 2415; AV=1418; ES=9; SD=5
33,5 grs H4350:
http://i1167.photobucket.com/albums/q623/stgw77/H4350reducedload1_zps6adca08e.jpeg?t=1370439438
Velocity: 2455, 2469, 2478; AV=2467; ES=23; SD=11
Case was filled 80%+, and so far I am extremely happy with accuracy
I know that 3 rounds are not a lot, but looks promising so far...This reduced load has POI only 1"-1.5" lower than 2800 FPS load at 115 yards... rifle recoils nearly the same, no big difference. This will be my 100 m & training load, maybe I will shoot it at 300 m also...need to try that...No stability issues so far. It would be good to know how long my bbl would last with this load, reduced for 400-500 FPS (!!!), pressure should also be very lower also, brass should last long...Please try to put numbers into QuickLoad and publish them. If you try this load (on your own risk of course), also please share your experince with us!!!
Best regards from Europe
