Comparison of velocity and energy downrange.

[Ignition Override]

Where can one look up, for plinking awareness at 50 or 100 yards etc, what are the differences in energy and velocity between an SKS, LE Jungle Carbine and MN 44 or 91/30?

The SKS uses Russian-made and the LE British ('43) or Pakistani ('62 or so) .303.
The very inaccurate MN 44s, 'good old' Bulgarian.

Though this is academic, do the surplus .303 rounds lose energy at longer ranges (i.e. 200-300 yards) much faster than surplus 7.62x54R from the MN 44?
Some might prefer that we all use US-made ammo, but it costs far too much and most of us carefully rinse the bores then dry, when finished with surplus.

 

[General Geoff]

Depends on the ballistic coefficient of the bullets in question. Spitzer (pointed) bullets tend to retain more velocity at supersonic speeds over a longer period of time than round nosed bullets. There are a lot of other factors involved (specific and sectional density, projectile weight and length), but I don't know too much more about it.

 

[Ignition Override]

They all seem to be Spitzer-shaped, like the nose of a certain F-105 "Thud" which went at mil-power towards Haiphong Harbour for an 'off-limits' Russian merchant ship (SA-2 cargo).

If we assume very similar bullet weights and similar densities/center-of-gravities in both types of surplus ammo, along with classic x39 data, maybe it would only be in a book for reloading.

 

[General Geoff]

Assuming identical bullets in the .303 and 7.62x54 rifles (they both use .311-inch diameter bullets), and similar powder charges, then they should have extremely similar external ballistic properties, including trajectory and velocity loss.


edit; from what I understand, .303 British was loaded just a bit lighter than 7.62x54R, so you're looking at a ~200fps discrepency between the two with 150gr bullets. This would cause the .303 to have a deficit from the muzzle onward, generating a less favourable ballistic trajectory.