Wednesday, August 1, 2012

Custom Crosman Breech--Part 3 Magazine Channel

For some reason, this still isn't in the trash can--I'm as surprised as anyone.

Need to cut a slot in the breech for loading the pellets.  Figured out where the breech end of the barrel will be located and drew some lines.

With some 1-2-3 blocks and an insert vise clamped to the table, I fashioned a work stop.  This should allow me to insert/remove/insert the breech from the milling vise with some level of repeatable accuracy.

Hopefully, if I cut between the lines...   Yeah, right.  I set the table travel stops for added insurance.

Kept deepening the slot and eventually didn't think there was enough breech left in the vise for a secure hold.  Figured I'd grab as much of the breech in the vise as possible.

Blocked up the free end with a jack screw and a clamp.

Right up against the jaws.  I think (hope) this was the clutch moment for the project.  Getting the slot cut to the correct width and the proper depth was key to making the breech fit the Benjamin Marauder magazines.

As I seem to have only .22 cal Marauder mags on hand, I guess it's gonna be a .22.

The mags lock into place on the end of the 7/16" diameter barrel.  They require a bit of barrel protrusion into the slot, but that's just a matter of adding a setscrew to hold the barrel in location.

Mag snapped in place.

Still a ton of ground to cover and lots of ways to screw up.  Marked a center line on the bottom of the breech--this fits against the gas tube.

A 7/8" ball mill will match the curve of the gas tube.

I think that'll be OK.

Still need to deal with the cocking pin and bolt handle slots, transfer port hole, a transfer port, a longer cocking pin, bolt handle, mounting screw holes, provisions for sights/optics...   Probably a couple more posts.

As always, thanks for following along.

More soon.