doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Hosford Company vs Galazan barrel wall thickness

Hey Chuck, perhaps something a bit more Boeingy is called for. A few yrs. back, you were talking about oriented carbon composites for the internal rod. Is that still on the drwg. bd.? No one (including the advocates of portability) who's fiddled with this can have much objection to a lightwgt. external truss but the rigid internal rod is the Grail. Anything new doing there? Any developments not involving the physical limitations of calipers? Lasers, medical imaging process calibrated to measure? Or are we stuck in the anodized gimmick approach?

jack

Well, just my opinion, but having just used my similar gauge both vertically and horizontally, I find I get more consistent readings in the horizontal position.
Zeroing the gauge looks odd, as you have to hang it near the ball to set the dial, but it does seem to work well in the flat position.
Partly (IMHO) because the ball finds the bottom of the tube naturally by gravity.

Jack,
I've been using the carbon fiber setup for a while now. After some use, I find that the carbon is about the same flex as the steel. The only thing I can see helping is boron filament or tungsten carbide. A rod long enough to get into a 28g or 410 is just so small it has a lot of flex unless it's a super modulus like the materials I mentioned.

Point of clarification from the "hang it vertically" proponents: I understand the benefit that oldstarfire gets from horizontal orientation. Most of the guys who hang it have the modification proposed by the late Oscar Gaddy--a music wire spring added to the internal rod and acting against bore wall to force the anvil ball against the opposing wall. Some of the "tabletop" gauges have similar provision through a pivoting brass arm actuated by a small coil spring. Without the "Gaddy mod", the Manson tuning fork type would be useless suspended from overhead joist, SUV or minivan deck or what have you as would be the tabletops.

jack

I use a gauge built on the same principle as the Hosford gauge. It is called "Truth Gauge". Used with the barrel in horizontal position. Having used both the upright table model and mine I have far more faith in mine. The flex being discussed is really no concern once proper technique is understood. And with gravity holding the ball firmly against the inner wall there is no error from that. An added bonus is it's highly portable. I always take mine to gun shows and it has saved me from a bad mistake a number of times.

I'm in agreement that using the one gage horizontally you will have flex, how can you not. Even by holding onto that ring, how do you know you are holding it the same the farther you go.

Oct 2008, I started making a horizontal one, but had it supported on both ends, one end was fixed and the other end went into a fit on the top and lower rod. Indicator traveled on a square tube. Took free end off , inserted barrels, then put free end on and zeroed indicator on that side. Lifted needle and moved to far end and made sure it was zeroed there. You would have to zero it on the ball bearing at both ends.
Sounded great, except I forgot about the choke section.
Now have another idea, same principle, except on the lower rod drill for a 3/8" ball bearing to be inserted on both ends of the rod the barrel rests on. This would take car of any choke and any unforeseen areas in chamber. The barrels would only be resting on two points. The muzzle end would be on the fixed end and far enough away from any choke area. The breech end could be made so that if using barrels between 26-32" that it would read all.



On the free end the square could be filed so that it slipped in easily, and on the rod end it could be a .002 larger and both could be secured with a wing nut. On the fixed end a set screw would do.

Using 3/8" rod with a 3/8" ball bearing, would give you about 9/16", good for 10, 12 or 16 ga. Any thing smaller and you might have center flex, maybe.

I have been to the proof house and they had a Galazan gauge there. The other gauge would work good if it was for tubes only but with lumps on it. The Galazan gauge is designed that is time proven and centers the weight down at the bottom. Galazan did not design it, it is the same gauge that has been used in the trade for 100 years. There are many people that make them besides them.

The 12/16 size on most any of the gauges, especially the Galazan type, is plenty good. It's the 28/.410 size that is really the challenge.