Excellent illustrated article on WW1, WW2+ anti-tank rounds.

My apologies if already posted . One look at the standard US 75 mm vs one of the 88's would cause one to pause !

http://www.quarry.nildram.co.uk/tankammo2.htm

I cannot find the article now but remember reading about German 50MM barrels being tapered to "squeeze" the projectile, or sabot, to delay dwell time allowing powder to burn and pressure to build to increase velocity. Was I day dreaming or was such a barrel made. Machining it would seem difficult. Quite different from a discarding sabot.

Gaines

 

Interesting comparison photo's, thanks for posting.

 

Yes, there were two German guns made with a tapered bore. Their purpose was similar to that of a discarding sabot system - greater surface area for the expanding propellant gases to act on, with smaller cross-section to maintain velocity after leaving the barrel.

Here is one example.

These guns proved very effective - so much so, that the Allies produced some adapters to add tapered bore capability to standard anti-tank guns - the 2-pdr and the 57MM. These were not as successful as the German designs, and were discontinued after effective discarding sabot rounds were developed.

 

Many thanks, especially the link. I can imagine they were difficult to manufacture. The easiest way I can think of would be over a mandrel or perhaps some form of eccentric boring. Rifling a cone shaped bore presents challenges but complexity was a German forte . I am reminded of Swiss watch makers referring to lunar dials, dates, stopwatches built in as "complications" as a category, not meant to be derogatory, just realistic !

To do so in a 2.8 CM barrel is impressive.

Gaines