I too had always heard the rumor that some of the whips in Raiders may have been made out of kip (calf skin).
However, I recently found the following information on David Morgan's website:
The 450 series bull whips were developed at a time when kangaroo hide, and so Australian kangaroo hide whips, were embargoed, and we could not obtain the Australian bull whips we had been selling to performers. The design of these whips was based on the older American bull whips and the needs of performers presenting American style stunts for movies or stage such as wraps, snatches, lifts, cutting or target work. The construction chosen was the Australian style, in this case with two inner braided bellies. The first whips were made in kip, the leather from young cattle, but as soon as kangaroo became available again a heavy weight kangaroo was used, with the strands cut wide for durability. The design established was for a heavy whip, well balanced with a loaded butt, brought to a point finer than the old bull whips, and with an Australian type fall and cracker. The taper or shape of the whip, a critical factor, was made to suit the basic stunt needs, including target work and close cutting.
Also on DM's site;
In 1973, the US placed an embargo on kangaroo skins and products, effectively stopping the supply of Australian whips and braided goods to the US. David decided to keep the trade going by crafting whips from domestic calf skin (kip). He produced an American style bull whip using an Australian braided belly construction. This whip style, the 450 Series, proved popular among stuntmen and performers and was used in the Indiana Jones movies. Once the embargo on kangaroo products was lifted in 1981, David switched to crafting these whips from the stronger kangaroo leather and the company renewed the importation of Australian leather goods.
According to the two statements above from DM,
1. The very first 450 series whips were made of Kip (calf skin)
2. DM did not start producing the 450 style of whip in 'roo hide until 1981.
If this information is correct, then it is not a rumor.
All of the whips used in Raiders would have been made out of Kip and
NOT 'roo hide.
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