Unfortunately I'm not going to be of much help ecept to say that with the two different limb length I don't believe the ATA would be the same. The 14" limbs would have to make a longer bow with a higher brace height.
I am fairly certain that the Slayer was offered with both limb lengths in 2005. With 14" limbs it was just called a Slayer and had an IBO of 325 fps. With 13" limbs it was called a Slayer Extreme with an IBO of 335 fps. Of course this was probably with the C Nitrous cams.
The Extreme is listed at 37.75" ATA so just using my noggin I would think that 38.25 would be pretty close to correct for 14" limbs. Here again, I could be wrong. It happens. And what changes were made for 2006 is open for discussion.
I tried going back in earlier catalogs and didn't find much more than what is in the spec sheets. In fact, for 2004 the Slayer is listed at 35" ATA which I know is wrong because I had one with 14" limbs and I remember it being closer to 38".
I'm not questioning anybody's knowledge here, but being as there is so many different figures being tossed around here I would suggest calling JoelC at Martin and getting it straight from the horse's mouth.
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