Crossbows - Everything about Building, Modding, and Using your Crossbow Gear

Latest topics

» Crossbow with built in lever?
by kenh Today at 6:21 am

» Chinese crossbow with auxiliary string?
by stm2010 Mon Jun 26, 2017 9:48 am

» 15th century saxon prods
by Geezer Mon Jun 26, 2017 7:34 am

» Yet another one
by jocky Sun Jun 25, 2017 7:09 am

» Crusader crossbow
by c sitas Thu Jun 22, 2017 9:41 pm

» Whamo showed up, prod replacement ideas
by kenh Mon Jun 19, 2017 4:25 pm

» Renaissance Sporting crossbow
by tony a Mon Jun 19, 2017 2:10 am

» loose laminate issues
by c sitas Sun Jun 18, 2017 8:42 am

» Of Bows and Torsion Engines
by c sitas Fri Jun 16, 2017 2:55 pm

» My second crossbow
by Daniel Levesque Fri Jun 16, 2017 10:48 am

» Need to locate Windlass Crossbow, pre 1600, in Rome, Venice, or Florence
by 8fingers Tue Jun 13, 2017 11:24 pm

» Crossbow Projectiles
by Geezer Tue Jun 13, 2017 8:10 pm

» Greetings!
by OnlyHuman Mon Jun 12, 2017 7:40 am

» Anyone know what this is?
by Yuki23emma Sun Jun 11, 2017 2:54 pm

» Prod specs
by Onager Lovac Mon Jun 05, 2017 4:25 pm

» Finished Crossbow
by kenh Sat Jun 03, 2017 8:34 pm

» The Arbalist Guild - Around the World
by Turnigy Fri Jun 02, 2017 1:25 pm

» Reverse draw "compound" build
by Turnigy Fri Jun 02, 2017 1:20 pm

» Casting Resource
by White Oak Wed May 31, 2017 2:28 am

» The Road so far......
by White Oak Mon May 29, 2017 7:17 am

by Onager Lovac Wed May 24, 2017 6:41 pm

» Hello from Maine
by White Oak Sun May 21, 2017 11:06 pm

» Leonardo Da Vinci string with suport-rolls
by Oppenheimer Tue May 16, 2017 11:40 am

» Compact repeating compound project
by Phil Abrahams Mon May 08, 2017 2:10 pm

» Trying to reduce the power stroke in my next project
by octavioaugusto.oliveira Thu Apr 27, 2017 1:27 pm

    Is it better to have a bolt sticking out than not?

    War Song
    Fresh Blood

    Doesn't mean
    I'm new to crossbows

    Fresh Blood Doesn't meanI'm new to crossbows

    Posts : 29
    Join date : 2013-11-20

    Is it better to have a bolt sticking out than not?

    Post by War Song on Thu Nov 21, 2013 12:13 pm

    I see that most bolts are made long enough to stick out over the rails, I can see that this is needed if your bolts have broadheads that might not sit well on the rail, but what if you're using flushed points?

    Is there any performance advantage to the bolt sticking out rather than not?

    Workshop Savvy

    Did you see my tool collection?

    Workshop SavvyDid you see my tool collection?

    Posts : 192
    Join date : 2012-08-11
    Location : Germany

    Re: Is it better to have a bolt sticking out than not?

    Post by Rizzar on Thu Nov 21, 2013 11:45 pm

    The length of the bolt is not really important (neglecting FOC at this point).

    If your bolt lies savely in the groove or the rest everything is fine.

    Needless to say a bolt sticking out too long is some kind of inconvenient.

    A bolt that is very(!) short is usually coming with disadvantages in balance point inflecting flight dynamics.

    Relating to medieval, bolts were usually categorized (incidently read about it in "Die Armbrust" yesterday) by the type of Crossbow ("Halbe Ruestung" for example to be about 2.47oz (~1/45 of bow weight) and 15.35 inches ) with little or no adjustment to the weapon.

    When considering making long and narrow bolts compareable with bow arrows a thing comes to a point usually not wished with crossbows: spine and archers paradox.
    A long narrow bolt will bend during acceleration, a stout one would not be influenced by that so dramatically. But this phenomena inflicts bolt flight a lot and with high power weapons bolt breakage is more likely to occur.

    In conclusion: If you make your bolt with little differences to your rest you would do fine without running into trouble.

    Crossbow Junkie

    I live here!

    Crossbow JunkieI live here!

    Posts : 399
    Join date : 2011-10-16
    Age : 53
    Location : Capitol Area Maryland

    Re: Is it better to have a bolt sticking out than not?

    Post by Gnome on Fri Nov 22, 2013 5:34 pm

    From my personal experience I've found that bolts the same lenght as the bolt track they are fired from, or just a bit longer if a broadhead or other larger-than-shaft diameter point is used, fly truest. I've tried longer bolts or arrows experimentally, and there is always more wobble and other eccentric behavior. I have not tried ultra short bolts.
    Master Crossbowyer
    Master Crossbowyer

    Posts : 932
    Join date : 2010-01-12
    Age : 69
    Location : Austin, Texas, USA

    Re: Is it better to have a bolt sticking out than not?

    Post by Geezer on Sat Nov 23, 2013 7:30 am

    The geezer's eye view of long vs short bolts.
    Short bolts have less surface friction for their mass, so they go a little faster over longer distances, but they also go deeper in your target and hence tend to shed their fletching.  They're more compact and use less arrow-shaft.  I used to make 10.5 inch bolts as my standard because I could get three per cedar arrow-shaft. 
    My target-shooting customers often swear by longer bolts-16 inches or better, for stability... which might be true if the balance is right.  Using standard weight field-points, you can run into problems with insufficient head-weight for the shaft.
    Longer bolts stick further out of your target, so they don't shed feathers as readily, but long, whippy bolts can fail under acceleration or on striking the target obliquely.
    Medieval illustrations often show bolts protruding over the front by several inches, so they had to deal with the same question... extant medieval bolts run anywhere from 12 to 18 inches in length, but the average seems to be about 15 inches (38 cm) Given short draw and relatively high brace-height of many medieval and renaissance bows... say 5-6 inches of draw from 4 inches of brace, plus an inch or so extra ahead of the prod, we get maybe 11 inches from front of prod to the lock, for a 4 inch overhang.  And yeah, that's pretty much consistent with drawings/paintings.  So by medieval standards, a fair overhang should be no big problem.  Geezer
    War Song
    Fresh Blood

    Doesn't mean
    I'm new to crossbows

    Fresh Blood Doesn't meanI'm new to crossbows

    Posts : 29
    Join date : 2013-11-20

    Re: Is it better to have a bolt sticking out than not?

    Post by War Song on Sun Nov 24, 2013 4:10 am

    Great stuff Geezer, didn't think about the bolt burying itself Razz. I was actually looking to see how short of a bolt I can use, related to an autoloading system I'm trying to iron out. I remember reading somewhere that fin-stabilized kinetic penetrators (basically a cross bolt right?) have an optimal flight dimension of 20:1 length/diameter ratio.

    Not sure how well that would apply for the crossbow bolt, but with a 1/2 inch diameter shaft, that would make 10 inch as the optimal length.

    I guess the only way to know for sure is to experiment.

    Sponsored content

    Re: Is it better to have a bolt sticking out than not?

    Post by Sponsored content

      Current date/time is Wed Jun 28, 2017 9:34 am