| GENE SLOVERS US NAVY PAGES UNITED STATES NAVY EXTERIOR BALLISTICS 1935 COLD GUN CORRECTION |
| COLD GUN CORRECTION REFERS TO A CONDITION THAT WAS THOUGHT TO BE THE RESULT OF A GUN BEING COLD AND FIRING OF THE FIRST ROUND THROUGH A COLD GUN WHICH RESULTED IN A SLIGHTLY SHORTER RANGE AND A SLIGHT INCREASE IN BEARING DEAVIATION. IT WAS LATER FOUND THAT IF THE GUNNERS MATES HAD SWABBED THE GUN THEN THE FIRST ROUND FIRED THROUGH THIS GUN, AND THE GUN WOULD BE COLD, WOULD BE SLIGHTLY SHORT IN RANGE AND HAVE A SLIGHT INCREASE IN BEARING DEAVIATION. IF THE GUNNERS MATES HAD NOT SWABBED THE GUN THEN THERE WOULD BE NO DECREASE IN RANGE OR AN INCREASE IN BEARING DEAVIATION. IT WAS FOUND THAT THE ROTATING BAND WIPES THE OIL FROM THE BORE OF THE GUN, BUT THE OIL BUILDS UP ON THE ROTATING BAND AND INCREASES THE FRICTION RETARDING THE ROTATING BAND. THIS CAUSES A SLIGHT DECREASE IN VELOCITY OF THE PROJECTILE CAUSING IT TO FALL SLIGHTLY SHORT OF THE INTENDED RANGE. THE REDUCED VELOCITY ALSO CAUSES A SLIGHT INCREASE IN BEARING DEAVIATION. TABLES WERE THEN PRODUCED FOR EACH SIZE GUN FOR THE AMOUNT OF THE RANGE REDUCTION TO BE ENTERED AS A SPOT FOR THE FIRST ROUND FIRED IF THE GUN HAS BEEN SWABBED. AFTER FIRING THE FIRST ROUND THE SPOT IS REMOVED. NO SPOT IS REQUIRED IF THE GUN HAS NOT BEEN SWABBED. THE BEARING DEAVIATION IS SO SLIGHT THAT NO CORRECTION IS MADE. THE TERM COLD GUN CORRECTION WAS THEN DEEMED IN ERROR BUT AS THE TERM HAD BEEN USED FOR SO LONG IT WAS AND IS CONTINUED TO BE USED. A DESCRIPTION OF THE OLD COLD GUN CORRECTION ERROR MAY BE FOUND COLD GUN CORRECTION 1315 |