.55 MK1 MK2 Question

[Weasel]

Can anyone tell me the difference between the MK1 and MK2 Boys .55 projectile's,
Best regards Weasel.

[Tony Williams]

The W Mk 1 fired a 60 gram bullet at 747 m/s, the W Mk 2 a 47.6 gram at 884 m/s (in old money, 930 grains at 2,450 fps and 735 grains at 2,900 fps respectively).

[Big Al]

I have owned 3 different Boyes ATR. 2 British and i Canadian.

I shot them in .55 Boyes configuration before converting them to .50 BMG.

The recoil on the Mk I was "severe". I am a big lad and I do not get pushed around by the recoil, I adsorb the full brunt of the "reaction". You begin to realize why the British built in a recoil mechanism AND a recoil pad.

The recoil on the MK II was almost as bad. After conversion to .50 BMG the recoil was less than MK II ammunition.

All shots were fired with the flat Canadian muzzle break mounted.

A "mild" load of about 130 gr of 4831 behind an 859 gr gas checked lead bullet was a delight to shoot with an estimated velocity of only 1800 ft/sec.

[Tony Williams]

Nitpick - the spelling is "Boys". I don't know where "Boyes" came from but it's a very common mistake.

[Weasel]

Hi Tony, thank you very much for your swift reply. Very interesting info,
Best regards Weasel.

[smle2009]

I think the Mk 1 projectile was slightly longer?
Cheers
Tony

[Chris 42 RQ]

Armour Piercing Mark I longer bodied projectile

Armour Piercing Mark II shorter Bodied projectile

[Weasel]

Thanks Tony and Chris for the added info and pics,
Best regards Weasel.