mlespaul

Greetings from U.S.! I'm Micah Meyers, and I am an optical and fire control system researcher and enthusiast. I specialize in german items, but I am compiling large research archive of many nations from 1914 through 1945. I assist militaria collectors and dealers (and restorers) with identification and valuing (up to a point) of found items and what weapon platform they went to and I am always looking for new and archaic information on anything that was looked through or operated to locate, observe, or fire upon a target. I rely on primary source documentation, like period technical manuals and instructions, then photographic details that I then catalog, I'm hoping to write a book someday (someday:red:). Please feel free to contact me if anyone needs help identifiying something. Just don't be surprised if I ask you to send some pictures of it, for my archive database! I especially like photos of the graticule/reticule, which often helps identify it's usage and intent. Cheers to you!

Hi all, Yes, the first assumption is correct. The 17pdr sight for the firefly was a specialized reticule as the tank telescope version required both coax MG and main cannon ranging scales. As the tank version of the gun was mobile and ranging and had to keep a constant "eye" on both stationary and mobile targets, that were constantly changing in distance due to both the movement of both target and tank a highly adjustable sight range was needed. In the Firefly, as you probably already know, the horizontal line moves vertically against the fixed scale as does the vertical line moves horizontally for deflection. As I have read, tank gunners of the period were not very fond of the left and right deflection behaviour of the graticule and normally left it fixed. But the telescope graticule that eddy posted above is a No. 43 x 3 L Mk. I for the Mark IV and VII gun and .30 mg. and the corssair does not move, it is fixed. The difference here being that the markings of height below the central mark provides for the height destinations and the distance markings laid on the target as called for and the gunner would read across the numerical scale to verify. This one went to Sherman C tanks. The main point is that the tank gunner needed to keep his eyes on the threats and could adjust the range while on the move without having to take his eyes from the telescope to look away to the range drum and back. The A/T version, already having the range drum mechanism, normally was only needed at the moment(s) of final direct fire, as the estimated distance had already been calculated and input to the carriage. Not only that, but the No. 43 x3 ML Mk 3 for the Mark II/30 cal MG (Challenger tank) and Mark IV and VII/30 cal MG (Sherman) were more complex and delicate instruments that had revolving rings that controlled the moving graticules and needed special care. Also the differing contractors made different installation brackets for the interior of the turrets and were not always interchangeable. Also the No. 43's and 57s (as also the other Mk gun telescopes for tanks) had a light path that required a definitive length for the prisms and mirroring configuration and so the accuracy of image reflection required a specific length of the telescope itself for the necessary glass partitions, which if you were to try to install it in an A/T carriage the length would make it impractical. Sorry to be convoluted, but everyone above is right, a different telescope for each application.:angel: You have to look at what the capabilities of range are for the particular gun first, then the optic was designed. You wouldn't get a telescope that was ranged for 3600 meters if the gun itself could only send a round downfield 1200 m .