Re: OQF 6Pounder mk5 to 75mmAugust 18 2012 at 11:56 AM
|Claus Bonnesen (Login cbo)|
from IP address 188.8.131.52
Response to OQF 6Pounder mk5 to 75mm
Calling the 75mm MkV a rebored 6-pdr is a bit of a stretch. It would be more corret to call the 75mm MkV a gun built around the internal ballistics of the US 75mm M3 gun using as many 6-pdr parts as possibly and able to fit in the 6-pdr gun mount.
According to the Churchill Mk VII & VIII Instruction book, the 75mm barrel was "externally similar to that of the Ordnance Q.F. 6-pr 7-cwt. Mk V" and measured 107.8 inches. As Brian points out - and confirmed by the Instruction Book for the Cromwells 6-pdr gun - that was shorter than the 112.2 inches of the 6-pdr Mk V barrel.
My guess is, that the difference in length and weight is found in the breech end of the gun, as 6-pdr cartridge was longer than its 75mm counterpart (441mm vs 350mm).
As for the thickness of the barrel, it stands to reason, that a barrel with thicker walls was used for the larger 75mm round.
- Gun balance... - Brian Colburn on Aug 18, 2012, 3:49 PM
- Elevation gears - Claus Bonnesen on Aug 19, 2012, 4:08 AM
- physical evidence - ian foster on Aug 19, 2012, 4:45 AM
- Absolutely... Unfortunately... - Brian Colburn on Aug 19, 2012, 4:52 PM
- Thanks all - ian foster on Aug 22, 2012, 3:50 AM