A 25 Cal Fortitude

[bear air]

I have that exact same stock on mine John, same color and everything. I should be getting mine back soon. A buddy did a bunch of work on it for me. Looking forward to reading the whole thread.

[FuzzyGrub]

I have that exact same stock on mine John, same color and everything. I should be getting mine back soon. A buddy did a bunch of work on it for me. Looking forward to reading the whole thread.

I got it off another GTA member.  It is nice and he did some minor inletting for the Mrod trigger.  I do think I'm going with the varmint thumbhole, posted earlier, and use the AT-one on the re-vamped 22 Maximus prime project.  The blaze orange sticks out too much for me, for field use.  Fine for bench and plinking. 

[bear air]

I agree that orange is very vibrant. It is my wifes gun and it will be a target shooter and plinker for the most part.

[FuzzyGrub]

The crosman 25 cal barrel did arrive.    Definitely a crosman, 6 lands, not GM.  I pushed a few JSB's through it, and found it just like the previous, with a very tight choke.  I did not find any burrs that were taking chunks out of the pellet.  No visible issue with rifling.  Barrel was relatively clean, too.  Installed it in a mrod.  Groups were single pellet hole at 10yds and consistently hitting 1" spinners at 50yds.  Declared the accuracy good enough to start the machining, which voids the 30 day warrantee.  Also, the leade, like the other one, chunky on probe closed. 

This will go on the caveman lathe to turn down the very first 0.060" to 7/16" from 1/2", so the standard Seneca aspen 25 cal mags will fit.  Otherwise, the same machining I did before:

- Side clearance for the two breech screws
- TP to 0.187"
- Smooth leade
- Flat for new shroud mount location

After 6 days, gauge hasn't budged, so declare it leak free. 

JFYI, I counted the first land twice.       The crosman made 25 cal barrels only have 6 lands, compared to the GM which has 10.

[FuzzyGrub]

Using the caveman lathe, put the step in the breech end, for the 25 seneca mags.  For doing flats, used the 1/2" shaft collars to help guide the file.  That worked much better than freehand, especially on the flats for the breech screws, which just need some widening.  The flat has to go on the angled part.

Mrod barrels, depending on the mechanical tolerances, can fit the Fortitude/Prod breech with no mods, but with a slight mis-alignment of the TP.  If you align the barrel port, centered in the breech opening, the barrel extends a hair too far into the breech slot and the mag won't fit or is very tight.   I took a few thousands off the barrel and chamfered it.  The Seneca mags snap in, but not overly tight. 

Assembled it back together and was nice to see the chrony reading high 860's with the 25g JSBs.  Right where it was before.   

Need to make a trigger guard, and modify the existing barrel band to add some non-rigid support, to at least prevent the shroud to air tube ringing.