Oh, VERY interesting indeed.   Reads a lot like the machine tool acceptance protocols I used to work with.  Saved for future review.  (I still read stuff like that for pleasure.  )  Thanks!

uscra112 wrote on Feb 26^th, 2018 at 6:08pm:

Page 50 has a sample assessment sheet, I don't know if they pulled those number from a hat, but velocity's are in the 11-1200 range and pressures 20K +

Canuck 65 grain plated, smokeless, 1124 fps. out of the Favorite.

Sorry, 22"

Shot Two rounds of  UMC 1118, 1112 fps. tonight, these were blackpowder.

I received two different bullets to try. Both are .251" diameter, but the rifle's groove size is .257". So I made a .258" bullet expander die and adjustable plunger. Using an arbor press, they were easily swaged to .258". They are a little shorter and blunter now. But the rifle doesnt care   This gives me something to start with. In addition to the one cartridge I made, Im going to try the easy way - breech seat the bullet and use a .27 cal brown power tool blank.

ndnchf
I'm currently working on a Steven's Favorite, that is chambered for the 25 Stevens RF.
The barrel shows a .251" groove diameter, on both the slug and extended chamber cast. I've posted pictures of the preceding, in the Collectors section, under "Lucky Favorite".
I've fired a 27 caliber nail gun cartridge (green), without a bullet and the case fires and extracts as it should.
The .251" bullets arrived this weekend and the brown nail gun cartridges are on their way but I'm still undecided, as to the best way to test fire the Favorite.
I suspect that a lathe turned cylinder or proper sized tubing, with a 22 caliber blank, press fit,  at the breech end, as a primer, a small powder charge and a bullet in the front end would be the least stressful to the little Favorite. 
A brown nail gun cartridge, with a breech seated bullet, would definitely be the easiest  way and maybe even the most accurate.
The smokeless load velocity, for the 25 Stevens, is listed as 1180 fps, with a 65 grain bullet. Do you plan to check the velocity when you test the brown cartridge and breech seated bullet? If you do I'd be very interested in the results.
Otto

Your best "primer" for rimfire adapters is a 6mm acorn blank. 

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These are much easier to push out of your adapters than nailgun loads.   I use nothing but in my .32 adapters.  Not as cheap, but your adapter will last longer.

Look closely at your firing pin strike.  It my be that the hole in the adapter can be on center, rather than offset.

When I have used .17 wsm cartridges to make .25 Stevens, I trim the cases off just below the bottle neck, then expand the case to except the bullet. Yes, the cases are a bit short, but they are longer than the factory .25 RF shorts. Finding.17 wsm ammo in stock locally is probably nearly  impossible still.

Looking forward to seeing your results with the brown.27 nail gun loads using the chronograph.