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you read all kindsa yang around about this so i'll straighten it out for all our members .
as strange as it seems there is very little difference in trajectory (too 400M) between this heavyweight bullet and nominal loads . the big difference is about POI shift caused by a change in port pressure timing , forceing the barrel lower just before bullet exit . this has nothing to do with external ballistics . the recoil even felt more pushy .
instead of siteing in at 100M , on -3- , too +10" POI above POA , you would site in too +12.5" to acheive the same 300M zero . the 154grs 300M MRT = about 15.5 " instead of the normal +12.5" or so . there is only a few more inches of drop at 400M .
TULA CARTRIDGE WORKS polymer cases
WOLF___154gr SPBT____1.030"__ .309+"__________ semi-pointed lead meplat . 5s tangent radius ogive . no colored sealer . heavy casemouth crimp . BT= 0.180" long x 0.258" dia. no heel crimp . flat and flush exposed lead core .
_________________________________________ 0.205 G5 @2100fps MV
CHRONO DATA
10shots measured @15ft. , 65F. overcast lt.rain , 16.25"barrel . new polymer coated-caseings ammo .
AVE. (of 9) 2094 fps
HI , 2112
LO , 2061
ES , 51 fps
SD , ?
2083* , 2108* , 1829*(.error), 2098* , 2099 , 2112 , 2100 , 2104 , 2061 , 2081
CORRECTED AVE. MV at range conditions : 2107fps
measured @15ft. :2094fps
hit the jugs @50ft. :2064fps
@50M : 1973fps
@100M : 1841fps
RECOVERD FROM WATER JUGS @50FT.
R.Frontal Dia. = .450" to .490" (the smallest/largest dia. on all 3 bullets)
R.LOA of cores = .670" , .654" , .640"
unfired bullet LOA = 1.030" , core goes from tip to base .
all separated from jacket which broke off some ogive petals while the rest just curled back a little at the tip .
BULLET REPLACEMENT ?
if you could come up with a .310" bullet like the .308" 155gr match palma with its high B.C. (compared to this blunt wolf softpoint that is) @2000/2100fps you'ld be well on to the most efficient 762x39 load possible with a trajectory nearly the same as standard M43 but retaining 500ft.lbs. energy out to about 520M @standard conditions .
current M43 or Wolf FMJBT retain 500ft.lbs. out to about 400M , the HPBTs too about 375M , M67 to about 325M and the stubbie US made bullets to only 300M .
since carbines can use every fps/ft.lb. available , thats a lot of improvement for the little 762x39 case !!!
as strange as it seems there is very little difference in trajectory (too 400M) between this heavyweight bullet and nominal loads . the big difference is about POI shift caused by a change in port pressure timing , forceing the barrel lower just before bullet exit . this has nothing to do with external ballistics . the recoil even felt more pushy .
instead of siteing in at 100M , on -3- , too +10" POI above POA , you would site in too +12.5" to acheive the same 300M zero . the 154grs 300M MRT = about 15.5 " instead of the normal +12.5" or so . there is only a few more inches of drop at 400M .
TULA CARTRIDGE WORKS polymer cases
WOLF___154gr SPBT____1.030"__ .309+"__________ semi-pointed lead meplat . 5s tangent radius ogive . no colored sealer . heavy casemouth crimp . BT= 0.180" long x 0.258" dia. no heel crimp . flat and flush exposed lead core .
_________________________________________ 0.205 G5 @2100fps MV
CHRONO DATA
10shots measured @15ft. , 65F. overcast lt.rain , 16.25"barrel . new polymer coated-caseings ammo .
AVE. (of 9) 2094 fps
HI , 2112
LO , 2061
ES , 51 fps
SD , ?
2083* , 2108* , 1829*(.error), 2098* , 2099 , 2112 , 2100 , 2104 , 2061 , 2081
CORRECTED AVE. MV at range conditions : 2107fps
measured @15ft. :2094fps
hit the jugs @50ft. :2064fps
@50M : 1973fps
@100M : 1841fps
RECOVERD FROM WATER JUGS @50FT.
R.Frontal Dia. = .450" to .490" (the smallest/largest dia. on all 3 bullets)
R.LOA of cores = .670" , .654" , .640"
unfired bullet LOA = 1.030" , core goes from tip to base .
all separated from jacket which broke off some ogive petals while the rest just curled back a little at the tip .
BULLET REPLACEMENT ?
if you could come up with a .310" bullet like the .308" 155gr match palma with its high B.C. (compared to this blunt wolf softpoint that is) @2000/2100fps you'ld be well on to the most efficient 762x39 load possible with a trajectory nearly the same as standard M43 but retaining 500ft.lbs. energy out to about 520M @standard conditions .
current M43 or Wolf FMJBT retain 500ft.lbs. out to about 400M , the HPBTs too about 375M , M67 to about 325M and the stubbie US made bullets to only 300M .
since carbines can use every fps/ft.lb. available , thats a lot of improvement for the little 762x39 case !!!