AlNyhus
Silver $$ Contributor
Always a sucker for a project, here's the latest one.
It's an XP100, vintage 1963, the second year of production. The barrel was a bit of a unknown...no markings, no dies or brass came with it and whatever it's exact history has been lost through the years. There was refererence to it being a 17-223, which was a popular semi-wildcat (a "domesti-cat" as Randy Robinett terms it). I'm a .17 caliber fan, so why not?
First order of biz was a Cerrosafe of the chamber. Long story short, it's not exactly a 17-223, per se. It's a 17 on the 223 case but it retains the .17 Remington's .260 long neck, rather than the shorter neck of the .223. So it's either a long neck 17-223 or a .036 short .17 Remington...whatever fits. The stainless barrel is 25" long and of a straight taper....like a HBR barrel contour w/o the straight section. Neck is .205 by a pin gauge and it's twisted 1:10. There's a bit more freebore than we'd do now. I rummaged around through my dies, shortened up a .17 Remington f.l. die and shoved the shoulder back on some WW 223 brass until it chambered.
Expanded the necks of 5 cases over a .169 mandrel, drew them back (annealed), stuffed some 'too fast' powder in the case, seated a Hornady 25 gr. hollow point hard into the lands, lightly oiled the cases and headed for the range with only the barrelled action in my hands and a bit of hope in my heart. A 10 foot length of string with me to pull the trigger might have been a good idea, but hey....God's not big on cowards.
On the other hand...fools rush in where angels fear to tread! 
Cases f-formed nicely and the neck length actually increased from .015-.018 due to the light oiling and the aggressive draw back. No fingers were lost and an envelope went into the collection plate at church afterward.
Whipped up 45 more and drew those back.
It's an XP100, vintage 1963, the second year of production. The barrel was a bit of a unknown...no markings, no dies or brass came with it and whatever it's exact history has been lost through the years. There was refererence to it being a 17-223, which was a popular semi-wildcat (a "domesti-cat" as Randy Robinett terms it). I'm a .17 caliber fan, so why not?
First order of biz was a Cerrosafe of the chamber. Long story short, it's not exactly a 17-223, per se. It's a 17 on the 223 case but it retains the .17 Remington's .260 long neck, rather than the shorter neck of the .223. So it's either a long neck 17-223 or a .036 short .17 Remington...whatever fits. The stainless barrel is 25" long and of a straight taper....like a HBR barrel contour w/o the straight section. Neck is .205 by a pin gauge and it's twisted 1:10. There's a bit more freebore than we'd do now. I rummaged around through my dies, shortened up a .17 Remington f.l. die and shoved the shoulder back on some WW 223 brass until it chambered.
Expanded the necks of 5 cases over a .169 mandrel, drew them back (annealed), stuffed some 'too fast' powder in the case, seated a Hornady 25 gr. hollow point hard into the lands, lightly oiled the cases and headed for the range with only the barrelled action in my hands and a bit of hope in my heart. A 10 foot length of string with me to pull the trigger might have been a good idea, but hey....God's not big on cowards.
On the other hand...fools rush in where angels fear to tread!
Cases f-formed nicely and the neck length actually increased from .015-.018 due to the light oiling and the aggressive draw back. No fingers were lost and an envelope went into the collection plate at church afterward.
Whipped up 45 more and drew those back.
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A steel plug was made and green Loctited into place. Then a bit of JB Weld went over it and was lightly sanded to match the receiver profile.
