Understanding Draw Length Adjustability

[Superdoo]

I'm looking to get my first bow. I'd like to go the used route to save money. My draw length measures at 31".

My question is: If I look up the specs on a bow and it says the DL can go up to 31" and the listing says the DL is set to say 29", how can I find out if I will need new cams or a different module???

For instance, this chart from Prime confuses me.

 

[Billy Goat]

You really just need to look up each cam system. Some as you know have draw length specific cams, so even tho the bow is listed as a 26-31" draw, it requires a $200 cam to change draw.

Some have a rotating mod that is good for 2" adjustment, like 28-30, then you need a different cam.

Then you have rotating mods that can do the full range, at your draw length it's likely not as much of a concern, but for short draw shooters those are frequently the ones that loose the most performance.

So basically you will need to research the bow, and cam system. On some older models it might be year dependent as well.

The chart above is a reference of what cam provides what draw on what bow.

 

[Superdoo]

Where's the best place to find that info? I know I've looked up some bows and haven't been able to see a manual online. I've also not had luck in finding replacement cams on some of the bows I've looked at, which rules those out rather quickly.
If the seller has a close up of the cam and I can see the adjustments labeled out to 31" do I need to do anymore diligence?

 

[Billy Goat]

Most mods or cams are only going to be available from dealers, some smaller companies will send you components if you don't have a dealer close enough.


I'd read the tune charts, that will tell you if they use independent mods, rotating a mod on the cam, or individual cams.

Seeing 31" written on the cam might just be a draw stop position. It could still require a different mod to reach that point.

I don't know if the information for every manufacturer is complied somewhere or not.

 

[doncarpenter]

If you're looking at prime bows, they didn't have a rotating draw length module until the black series, 2020. So, from the Logic all the way back to the centroid and shift the cams were draw length specific. So, just like Billy goat said, you will need to find the right cams for which ever model your looking for.

I have had luck on ebay and the ArcheryTalk classifieds (cams, limbs, and module section) finding different sized cams for Prime bows.

The Black series went to 31", if you wanted 31" in the Nexus series you would need the Nexus 6, the others stopped at 30.5".

Sent from my SM-G998U using Tapatalk

 

[Billy Goat]

If you are looking at a particular bow and are in doubt, post a question. Someone here will be familiar with the it.

In general Mathews of the past half dozen plus years will use mods to adjust letoff and draw length.

Bowtech has been using a rotating mod.

Elite started to use rotating mods recently, prior to maybe 2020 they used mods to adjust the draw length, but you could still manipulate letoff on the same mod.

Pse has been using a rotating mod.

Hoyt has used different cams for different draw ranges (generally 1-3 different cams for different draw ranges) until the HBX cam. I'm pretty certain that's when they went to a singular base cam.

Prime for a long time used a different cam for different draws, but has recently changed to a rotating module.

Bear uses a rotating mod.

 

[NY12020]

@Superdoo
"Draw length specific" - you have to change the cams to change the draw length.
"Rotational Module" - you loosen 2 screws; rotate to a different set of holes, tighten the screws back up.
"Replacement Module" - you have to change the module to change draw length, but not the cam itself.

 

[dtrkyman]

Keep in mind the actual draw length listed for any setting is likely off, generally speaking they tend to run long, half inch on average, so the mod. position is just a reference, you need the bow set for you!

 

[Superdoo]

Keep in mind the actual draw length listed for any setting is likely off, generally speaking they tend to run long, half inch on average, so the mod. position is just a reference, you need the bow set for you!

It is so damn much easier to pick a rifle!!!!

 

[Billy Goat]

It is so damn much easier to pick a rifle!!!!

I think pretty much every company makes a good bow now. There's quirks with different brands, but really they are all good bows.