View Full Version : Scepter III Tune Specs????

02-21-2009, 08:34 AM
I've got a 2nd hand Scepter III that I'm having trouble with. Can't seem to achieve consistent groups. It feels to me as though the string and cables are not nearly as taught as they should be. I own many compound bows and all of them are strung much tighter. I've checked the draw weight and it's right on at 60 lbs (bow is rated for 45-60lbs). Also, the draw length seems to have increased all by itself. I'm wondering if the string and /or cables have stretched.
I've tried finding the spec chart here on Martins Website but I'm not sure how to read them. Trouble is I'm not sure what cams are on this bow or what year it is and there is no mention of a Scepter III in the listings from what I can find.
Any help with this would be greatly appreciated. Thanks

02-21-2009, 08:43 AM
With the small size cams, the cables will be inherently slack compared to the string as most of the tension is in the string. My S4 is like this too.

02-21-2009, 09:59 AM
Thanks Flytier. You're right about the cams. They are very small. Do you know what cams the Scepter III uses?

This is my first target bow. I was shooting better groups when I first bought this bow a few months back. Then I kind of quit shooting it for awhile and recently I decked it out with a competition 30" stab and counterweights and a Sword 3rd Plane Sight. Ever since adding these accessories I've been shooting much worse with it but then again there was a period of about 2-3 months when I didn't use the bow.
Just on the off chance that it's the stab and counterweights causing me to shoot worse I think that I'll take them off tomorrow and try grouping without them. Has anyone ever noticed their accuracy degrade after installing a long stabilizer on a bow such as this? Maybe I'm just not used to the added weight forward???
When I first got it I installed a hunting sight, D-loop and AAE Drop-away rest.
My arrows were touching each other at 30-40 yards. Now I'm getting two or three arrows to group within 3-4 inches and some fliers which open my groups up to 6-8 inches. (Fletching contact?) I'll check for that tonite when I get home from work.
Any other thoughts???

02-21-2009, 10:04 AM
Hey Razor62
Perhaps you could post some pics and we could ID the cams for you. Looks like 2004 was the last year the Scepter3 was offered. I believe the standard was the Nitrous cams but it was also offered in the true-Arc cams too.

At rest all three strings should have approximately the same amount of pressure on them. if they feel loose on a 60 lbs bow I would find that odd too.

I'm not discounting flytier17's comments, I've just never experienced that my self.

It's possible that the strings and cables have stretched how much did the draw length change? Is the brace height close to 8.375? if it's improperly strung I would expect the brace height to be off.

02-21-2009, 10:19 AM
If the cams are small, they could be Fury's (precursor to the Furious) cams. That is what I have on my Scepter IV.

02-21-2009, 10:43 AM
Thanks Guys. I'll try to take some photos and post them up here this evening.

The string and cables all feel somewhat close to the same amount of tension and to me it's not much tension compared to other bows that I've owned both past and present.

I'll measure the brace too. Where did you get your figure of 8.375" ? I need the specs for this bow and can't seem to find them.

Thanks again guys. I really appreciate your help.

02-21-2009, 05:10 PM
Try 'tech info" on Martin's home website. I looked through a couple of the years (2002/2003) and brace and ATA were there. Wasn't there for 2004. Maybe it's in the catalog.

02-22-2009, 04:06 PM
Sorry I should have posted this when I mentioned the brace height. It was in the 2004 catalog. If you go to this link and then scroll down you'll see links to the former catalogs.

02-22-2009, 04:07 PM
You can also ID the Cams that are on it by searching back through the catalogs. THey have pictures of the cam options for each bow.

02-22-2009, 06:11 PM
In 1003 when the Scepter III first came out it had Fury Cams on it. Then in 2004 Martin came out with Nitrous Cams. This is the 2004 Scepter III. page.



02-23-2009, 07:34 AM
In 1003 when the Scepter III first came out it had Fury Cams on it. Then in 2004 Martin came out with Nitrous Cams. This is the 2004 Scepter III. page.


Robert58 is correct.