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Old 04-03-2019, 04:27 AM   #1
mallardtone-man
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High stretch Small ID bands on with Ab Biller trigger mechs?

Hey guys I have an Ab Biller 42 that I use for hole shooting and low vis that I have been running 2x 18mm bands cut at 300 percent w/ a 42" 5/16" shaft on with pretty good results, however the more I learn about the advantages of shooting 14mm small ID bands at higher stretch (325-370) I am interested in giving it a shot on this gun to get a little more power/distance out of it, however I want to make sure that the trigger mech will be able to handle this kind of force and I won't likely end up with damaged sears or unreasonably high recoil before I do. Has anyone tried this with a biller? I am converting the gun to an open muzzle and will be shooting either a 7.5 or 8mm (5/16") 42" shark fin shaft.
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Old 04-03-2019, 04:45 AM   #2
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Re: High stretch Small ID bands on with Ab Biller trigger mechs?

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Originally Posted by mallardtone-man View Post
Hey guys I have an Ab Biller 42 that I use for hole shooting and low vis that I have been running 2x 18mm bands cut at 300 percent w/ a 42" 5/16" shaft on with pretty good results, however the more I learn about the advantages of shooting 14mm small ID bands at higher stretch (325-370) I am interested in giving it a shot on this gun to get a little more power/distance out of it, however I want to make sure that the trigger mech will be able to handle this kind of force and I won't likely end up with damaged sears or unreasonably high recoil before I do. Has anyone tried this with a biller? I am converting the gun to an open muzzle and will be shooting either a 7.5 or 8mm (5/16") 42" shark fin shaft.


Is that 42 of band stretch? Still a large gun for hole hunting! Personally I would prefer a 7mm shaft on that length. The 8mm might be hard to propel. I have no experience with that particular mechanism though.
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Old 04-03-2019, 05:18 AM   #3
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Re: High stretch Small ID bands on with Ab Biller trigger mechs?

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Is that 42 of band stretch? Still a large gun for hole hunting! Personally I would prefer a 7mm shaft on that length. The 8mm might be hard to propel. I have no experience with that particular mechanism though.
No, it comes out to about 31" of band stretch on a 42
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Old 04-03-2019, 05:41 AM   #4
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Re: High stretch Small ID bands on with Ab Biller trigger mechs?

I would even prefer a 6.5mm (max 7mm) on that band stretch.
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Old 04-03-2019, 08:20 AM   #5
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Re: High stretch Small ID bands on with Ab Biller trigger mechs?

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I would even prefer a 6.5mm (max 7mm) on that band stretch.
Yes, I was thinking about giving that a shot as well. I think ill probably try a 7mm x 42" and see how that does for me.
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Old 04-03-2019, 03:02 PM   #6
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Re: High stretch Small ID bands on with Ab Biller trigger mechs?

Heavier shaft more hitting power, remember spear mass changes are proportional to the ratio of the diameters squared, e.g. 8 mm to 6.5 mm is (8.0/6.5)^2 which equals 1.515 or a 51.5 per cent change in shaft mass! As kinetic energy is given by shaft mass x shaft arrival velocity squared divided by 2 the lowering of shaft mass reduces the kinetic energy of a hit. Compare an empty shopping trolley running into you at the supermarket, it will just bounce off, but a full one at the same velocity will knock you over.

The strength of materials depends on their cross-sectional area, all other things being equal, so there is just more rubber in a band with a smaller hole in it. However the wishbone ball or bead pushed into the smaller hole creates more stress on the rubber and can lead to peripheral cracking where the band swells to accommodate its presence. Usually the band wishbone securing ties or wedding rings create necking down stresses in the rubber that will crack the bands anyway as rubber under stress is preferentially attacked by oxygen in the air and that already absorbed in the rubber. As for the bore holes in the bands taking on water it is very unlikely, however as the band stretches the hole diameter gets smaller as its length increases and therefore the volume stays the same. Ditto with the rubber bands themselves, their volume never changes, they just swap length for diameter and to do otherwise their density would have to change and that just isn’t going to happen unless the rubber absorbs water which it can do on long immersion like you find in busted off bands laying on the bottom.

Last edited by popgun pete; 04-03-2019 at 05:08 PM. Reason: more info
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Old 04-03-2019, 06:31 PM   #7
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Re: High stretch Small ID bands on with Ab Biller trigger mechs?

That mech will take at least 150# of pull for several thousand loadings. It will get tight and jam usually,sometimes they will misfire.My LTD used the same mech as the other Billers and it had 3 or 4 mechs replaced in 13 years. 400 dives a year often cocked up to 10 times a dive and as many as 25.
That's with a single 19mm / 3/4 in rubber @ max elongation.
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Old 04-03-2019, 06:44 PM   #8
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Re: High stretch Small ID bands on with Ab Biller trigger mechs?

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That mech will take at least 150# of pull for several thousand loadings. It will get tight and jam usually,sometimes they will misfire.My LTD used the same mech as the other Billers and it had 3 or 4 mechs replaced in 13 years. 400 dives a year often cocked up to 10 times a dive and as many as 25.
That's with a single 19mm / 3/4 in rubber @ max elongation.
As a matter of interest have you ever checked the mechs that were replaced? I found the sear lever got a twist in it and the top of the trigger had deflected off to one side putting a strain on the sear box. They never cracked, but you could see where the lever had rubbed with a lot of band load on the gun (3/4" band at high stretch that just got to the wishbone notch). If the mechanism levers were thicker then it would be good for two 3/4" bands as the original Sea Hornet all metal trigger mechanism was good for that load, but those mechanisms are as rare as hen's teeth. Ray Odor made an all metal mech for those guns, but he never told me how thick the levers were on his version. Note that the Sea Hornet all metal trigger mechanism came in two versions, the standard levers, which I have in my custom gun, and the thicker version which I don't have.
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