Leupold BX-4 Rangefinding Binoculars

Adjusting draw weight. Update.

std7mag

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I'm wanting to adjust the draw weight (lower) on a used bow I recently bought.

Question.
Do this with the tension on the limbs, or release the tension?
 
On my bows it is turn counter clock 1 complete turn is about 4 to 5 pounds. You have to turn BOTH limbs the same ! If I were you I would call or go to a bow shop !
 
You will loosen the limb bolts to decrease the draw weight. You want to be sure to loosen each bolt the same amount. I go in 1/2 or full turn increments. You might want to tighten each bolt all the way so that you know that they are set the same, then loosen from there.
 
Per APA, 4 turns out is equal to 10lbs.
And that's all I intend to do.

Problem is that the bolts (screws) seem siezed.
I applied penetrating oil on them and let them sit for a couple of days.
I do have a good, snug fitting allen wrench.
 
Per APA, 4 turns out is equal to 10lbs.
And that's all I intend to do.

Problem is that the bolts (screws) seem siezed.
I applied penetrating oil on them and let them sit for a couple of days.
I do have a good, snug fitting allen wrench.
check for set screws, I have an old school bow that requires you to loosen a set screw before adjusting poundage.
 
check for set screws, I have an old school bow that requires you to loosen a set screw before adjusting poundage.
No set screws.
Talked to tech from APA. He said sometimes it takes some force to break them loose.
Egads!

I'm going to take the tension off of the limbs, as I'm worried about stripping the screws.

Yeah, they are that tight!
 
No set screws.
Talked to tech from APA. He said sometimes it takes some force to break them loose.
Egads!

I'm going to take the tension off of the limbs, as I'm worried about stripping the screws.

Yeah, they are that tight!

It sounds to me like you should maybe take it to your local shop. How are you going to take tension off the limbs? Do you have a bow press? Do you have a bow scale, or a scale of some type to validate what you are doing? I would not trust a (#lb per turn" rule of thumb.

If I were you, I would start by cranking them all the way in, and then do your witness marks. Right now you have no baseline to work from. Witness marks are smart, but if you don't established them at the hard stop, you don't know if your limbs have consistent tension. This all has the potential to effect your cam timing and the tune on the bow.

How old a bow is this?
 
It sounds to me like you should maybe take it to your local shop. How are you going to take tension off the limbs? Do you have a bow press? Do you have a bow scale, or a scale of some type to validate what you are doing? I would not trust a (#lb per turn" rule of thumb.

If I were you, I would start by cranking them all the way in, and then do your witness marks. Right now you have no baseline to work from. Witness marks are smart, but if you don't established them at the hard stop, you don't know if your limbs have consistent tension. This all has the potential to effect your cam timing and the tune on the bow.

How old a bow is this?
The bow is an APA Mamba 7.
APA bows come with a pin that fits into a series of holes in one of the cams.
Remove the pin from its storage place. Step on the string and pull bow towards you. Insert the pin & release the tension.

If you really wanted to, you can replace the string in your ground blind.
Don't know why you would want to, but you can do it.

I don't have a scale like you are talking about. I'm waiting for a friend of mine to be free that does have a scale setup to see what the draw weight is, and what I can get it to.

Per APA, "do not loosen more than 4 turns out".

I understand the use of witness marks and fully intend to do such.

As for age. The previous owner says that he hunted with it for 1 year, then it hung on his wall for 4 years.
I already have plans for string replacement.
 
Some pictures of the setup.
 

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Update.

Well, it appears that soaking the limb bolts with penetrating oil worked.

Tried to turn them today, and they turned fairly easily.

I'm still going to put this on a scale to find out what the original draw weight is.
 
String replacement.

Just a heads up that this process definitely DOES NOT release the tension in your limbs as the cables are still holding the bow in position. If you back the bolts out to far your gonna have a bad day even with that pin in place.
 
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