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Discussion Starter · #8 ·
Its true that the neck pilot isn't needed. It *is* just a preliminary conceptual drawing. I may well eliminate the neck pilot when I make it. I may actually try it both ways to see which has better function.

As for the extractor-- I'd have to study a rifle and see if the extractor retracts below the rim recess sufficiently that it wouldn't interfere with the gauging. I'm thinking it won't interfere on the 1867. On the 1889 I'll check. The firing pin possibly interfering with closing of the breechblock would be eliminated by using a centerdrill in the base of the gauge to provide clearance.

I appreciate the ideas and feedback.

Dutchman
 

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Discussion Starter · #13 ·
Dutchman, as to the gauge: Since it is on a shaft with a threaded end, have you considered making an adjustable shoulder to measure depth instead of multiple gauges for that?
hello Dennis

I am of the opinion that adjustable things get out of adjustment and that they usually do so at inopportune times. I do own a 12x36" lathe so making a 3 or 4 piece set is not a big deal. In the end I may well take Andy's advise and just use a simple rim gauge. The neck pilot was thought to be a prudent idea in order to ensure critial alignment but I may have been having crainial flatulence at the time:eek:. Bouncing ideas around is a good way to finalize a design. Simple is usually better.

As to oil hardening tool steel as opposed to water hardening.

I have a bunch of Starrett oil hardening chrome-vanadium tool steel in sizes from 1/8" round to 1" round and a bunch of rectangle and square sizes. Did some swapping a couple decades ago and ended up with 100 lbs of the Starrett 01. Its good stuff even in the annealed state so I tend to think of 01 when such applications come up. But it is also true as Andy says that 1018 carbon steel would work every dang bit as good in a home shop where it won't get banged around and nicked or burred. I believe some of the aftermarket throat erosion and muzzle gauges are left soft so as to not wear on a rifle barrel, though I'm a little dubious of that notion. You'd have to be sitting there daily shoving your throat erosion gauge in the breech end for it to hurt anything. Though from what I've seen of those heathen Garandophiles they probably do just that:).

Dutchman
 

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Discussion Starter · #15 ·
The 28,000/29,000 psi as recommended maximum load level in the old Norma reloading data may be the best we get and as bullet weight & velocities for the known samples of factory ammunition support this general neighbhood I'm content for the time being to use this figure above as max for 8x58RD in rolling blocks. Its not beyond reason to think this figure is the one to adhere to. Its certainly not too high.

And concerning Accurate Powder in Montana and the ballistician, Johan Loubser, I did receive from him today a reply to the note I sent concerning his recommendation of load data to a person of this forum (much thanks!) that was grossly excessive based upon erroneous data and current CIP maximum chamber pressure for 8x58RD. Johan assured me that Accurate would "immediately" adjust their load data recommendation for 8x58RD to split the load data into two catagories with the lower one being the application for the 1889 Swedish rolling block using the chamber pressure data from Norma as a maximum recommendation. This is an excellent step with this situation. I explained to Johan that I was walking the ragged edge of what knowledge I have in this area. The support of you all in this has helped more than you know. Its not a lone crusade. I have a feeling I'll be learning far more than I could possibly imagine during the course of this all. This 8x58RD thing is becoming very fascinating to me. I'm going to review Hatcher's Notebook in the next week to bone up on what information I can glean from it about chamber pressure and the like.

Galen - anytime you see me make an error in figures or assumption I hope you won't hesitate to let me know. This goes for anybody else, too.

Dutchman
 
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