The modern 7.62x39 and 30-30 brass and bullets are both adequate rounds but the 30-30 wiht heavier loads is hard to beat.
I pulled some test data of factory ammo and reloads and applied same atmospheric values.
Loads:
7.62x39 125gr Silver Bear. Gun saiga 16"
7.62x39 154gr Tula shot. Gun saiga 16"
7.62x39 135gr Sierra hpbt Reload R7. Gun Saiga 16"
7.62x39 150gr hdy.sp. Reload. Gun bolt 18"
30-30 160gr FTX - Hornady SPF. Gun 20" marlin.
30-30 190gr pp - Buffalo Bore. Gun 20" marlin.
30-30 150gr hdy sp.Reload. Gun Bolt 18"B.
Please keep in mind reloads might be worked up carefully and with quality brass and very old firearms
might not like the modern ammunition and might put too much stress on lugs or chamber. Not a problem
for the AK but in the case of very old levers check first. Just like the old 45/70 cannot take some modern loads.
Also keep in mind while speer points and match bullets are not recommended for 30-30 can be used safely in
a tube fed magazine given that one keeps one in the chamber, next follow up and then if more ammo is needed
one will need to make an inert round in between subsequent shots and chamber once, extract the dummy and
chamber again to get the live round into battery. This way one can load premium 30 caliber bullets w/o worries about
accidental ignition of the primer due to recoil in the magazine tube.
Not a problem in a bolt action 30-30 obviously.
The 7.62x39 can also be reloaded with 30 cal bullets (some rifling better than other like hybrid chambers and bores) but can also enjoy more power with quality brass and premium bullets.
Variables.
1005 BP.
10C.
555 OSL
5mph wind.
200 yard zero.
Speed
Path
Energy
Momentum (Power Factor)
As you can see the 7.62x39 is a decent round specially with heavier 150gr bullets and while a better option than a 30 carbine or a whisper/blackout, it should be limited to 150 yards-200 yards
taking into account striking speed. But the 30-30 provides a significant advantage no so much
on speed or trajectory but in power and therefore capable of taking on larger game, longer range
and/or faster kills.
I hope this helps.
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