Accuracy of the Claplock versus Rollernut

Finally getting around to making another crossbow,  I have the prod ready to go and the wood for the body all selected but trying to figure out if I want to go with a roller not or a claplock.  It comes down to inherent accuracy is one system more accurate than the other?  I like the Claplock because it is a little faster to lock up, don't have to roll the nut back in place, but the string is always in contact with the bolt with the roller nut, which seems a bit more reliable for accuracy.  Am I over thinking this or is there a difference?

Hello Bas. Can't say much here about which is better. I can tell you that to my knowledge there are no such commercial triggers in use. I mean as the clap lock. All use the roller in one form or another.Could be some thing to do with the anti dry fire mechs . They all use that now. A clap lock might present a challenge there. A roller is simple to do.Just my thought here, the more contact you keep between the string and the arrow the better it is.

Geezer here, concerning the claplock vs. roller-nut.  Personally I prefer the roller-nut: it's quieter, a bit more efficient, and produces less wear on bowstrings and bolts Mostly that's because the string is moving when it hits the bolt.  So there's a 'pop' representing a loss of energy.  That's my preference.  But in fact, there are lots of very good German light hunting and target bows made with the more sophisticated clap lock. (string slopes down to be held by a claw) Given the large numbers of extant claw/claplocks, I can't believe they were generally inferior to rollers.  Pushpin/notch claplocks are much simpler still.  Their major advantage is ultra-simplicity and very quick loading. They're cheap too. Though I make pushpin/notch bows (Skane bows) in my shop for sale, I don't personally like them very much. But boy, they build up fast.  I can easily turn out a Skane bow every day.
As for notch/claw claplocks, Garvin's Slobows has the parts for sale.  You should be able to make one up pretty easily.  Don't let me stop you trying them. Geezer.

Hmmm: I don't think I was clear there.  The string is moving when it hits the bolt in a Claplock or a Skane bow (pushpin/notch) The string starts against the bolt in a roller lock (or should if you're doing it right.) roller locks have less misfires and accelerate the bolt more smoothly, for less wear on bolt-butt and bowstring.  Geezer.

Thanks for the info.  I think I will stick with the simple roller nut for this one and save the complicated build for the next crossbow.

I just wanted to post the same question Bas;
before I start my RDT project, I upraded the bow that I made when I was 17. I changed the roller-nut mechanism for a (self-invented) claplock, because the lever that holds the roller-nut on the botttom wore down and it started to dry-fire. It was a lot of work to get it right, because when cocked, the lock has to be just above the rail.
So I made a new claplock-mechanism:

[img:9d7a]https://s20.postimg.org/ktd75wdll/IMG_0993[364].jpg[/img:9d7a]



It works fine, but it makes a lot of noise. When shooting it sounds more like a gun.. Besides that the serving on the string wear down quickly I guess, like Geezer says.
Two things to notice when you make a claplock I think: the front end of the lock that holds back the string has to have an angle, and must be a bit rounded, and the rotation-point must not be to low (some mm above the top of the string). I made it a bit to low.

I developed a trigger mech for my RDT project:


But now I am planning to change this in a lock that rotates under the string.. More to come.