String Stretch

[HOPEMILLS450R]

Hey Yall , Got a problem . I own a PSE Firestorm X and shoot around 200 arrows a week through it . Here in the past 2 weeks my shots keep dropping and I have to adjust my sights often . Is this normal ? THANKS

[davepjr71]

It sounds as if the string is stretching and moving the knock or D-loop up. Check to see if your knock point has moved. If so add twists to thebottom to move the knock point back down.

It should ahve settled thru the first 1000 or so. Notafter shooting that much.

I don't know anything about the quility of the PSE strings but it sounds like you should invest in good aftermarket for gibblet, Winnerschoice or other quality aftermarket string.

[BGfisher]

What Dave said about aftermatket strings is corretc. It's one of the best things you can do for a bow.

Besides string creep (not stretch) it could be simply that your nocking point is sliding up the serving or the serving itself could be sliding up the string. It only takes a little bit to change things a lot at the target.

[HOPEMILLS450R]

ORIGINAL: davepjr71

It sounds as if the string is stretching and moving the knock or D-loop up. Check to see if your knock point has moved. If so add twists to thebottom to move the knock point back down.

It should ahve settled thru the first 1000 or so. Notafter shooting that much.

I don't know anything about the quility of the PSE strings but it sounds like you should invest in good aftermarket for gibblet, Winnerschoice or other quality aftermarket string.

I just looked it over . I don't think the loop has moved but I would not place money on it . I've owned it since around the 1st of feb. bout it new.

[bow_hunter44]

ORIGINAL: BGfisher

What Dave said about aftermatket strings is corretc. It's one of the best things you can do for a bow.

Besides string creep (not stretch) it could be simply that your nocking point is sliding up the serving or the serving itself could be sliding up the string. It only takes a little bit to change things a lot at the target.

My ignorance is showing again, but what is string creep (not stretch)??

Thanks!

[Straightarrow]

Here in the past 2 weeks my shots keep dropping and I have to adjust my sights often . Is this normal ? THANKS

Definitely not normal. In order to determine the problem, you should carefully measure and record certain critical distances like brace height, ATA, nock distance from cam, peep location (if you use one), cam position, and tiller. This has to be done when the bow is in perfect tune and shooting broadheads exactly as it should. Then, it's easy to figure out if anything has moved and what has to be done to correct it.

bow hunter44, "creep" is the permanent elongation of the string. "Stretch" is lengthening that returns to normal (like a rubber band). All strings have at least a small amount of stretch to them. It is not something to worry about. Creep on the other hand, is very bad. If it happens, your bow is no longer in tune. Changing a sight position will not correct the problem.

[BGfisher]

Staright arrow described the difference between creep and strtch very well. I would add that what happens when a string creeps is that the nocking point moves to a different position. The draw length gets longer and the weight increases.

With a single cam bow it is more pronounced because the string, being approximately twice as long as the cable creeps twice as much as the cable. This is why many of us set our bows to specs and record the measurements such as brace height, axle to axle, bow weight, tiller, measured draw length and such with the bow in specs. I find it very usefull to also mark the side of the cam where it passes through the limb fork (both sides of the limb, front and back) to be able to see in what direction the cam moves and how much. It's a quick reference to look at if the bow starts shooting differently.

The main difference between most factory strings and after market ones is that good ones are wrapped on a jig and then prestretched and twisted to proper length, served under pressure. Most factory strings are not. Therefore they do their creeping on the bow so after you tune the bow they are constantly creeping till all the strands are doing equal work. Some quicker than others and some never quit.

If and when things get out of whack enough that twisting the strings becomes necessary to get the bow back in specs then twisting makes the bundle smaller and then serving movement or separation becomes a factor, especially around the draw length module where the radius is smaller.

It has very little to do with what material the strings are made of. It's in the string making process. Some companies are starting to do a better job of string making, but most are still way behind. And some of the upper line bows already come with strings from Stone Mt, Vapor Trail or Winner's Choice, or others. Again, most don't.

There are a lot of little things that makes some bows shoot better than others. Quality strings is one of them. Proper nock fit is another (a different subject). It depends on how picky you want to get. If you want to excel in the accuracy department then you do your homework. Simple as that.

Hope this helps explain things a bit.

[HOPEMILLS450R]

Thanks for the help and the info yall ,I really learned a lot from this thread . Hopefully I can get to the shop this week .