.25 cal Umarex 1894 Conversion
Posted: Wed Mar 18, 2020 12:20 pm
Imgur album below
I picked up this fun .177 rifle last year. A handy little lever action and a decent plinker, but I actually primarily wanted it for the mechanism which imitates the real gun with shells that chamber and eject with a wonderful metallic ratcheting. I spend a lot of time loading empty shells, working the lever, and watching them eject and fly all over the place, quite cathartic. It wasn't long, however, that I realized that the unique shell-loading allows for a huge range of ammunition to feed, darts, pellets, bbs, 4.5mm metal rods, anything of the correct diameter and not longer than the shell will work.
To convert this rifle I started by increasing the tension in the hammer spring to give the valve a little harder kick which increases co2 usage and power. This thing runs off of 2 12g co2 bulbs, you get around 90 shots from those 2 bulbs, so even if you double the output you should still get a good number of shots per fill. Then I needed to swap out the barrel. This was a fairly straightforward process as the barrel is just a simple smoothbore and resembles an airsoft barrel. The rifle disassembles beautifully, it takes little more than a minute to bring the gun down to the point where I can pull the barrel, breach, and magazine tube out, the valve, co2 chamber, and lever action linkage can be dropped out in less than 5 minutes once you get familiar with it. You could literally replace valve o-rings in the field so long as you had a screwdriver and pliers.
Anyway, a few dremel mods are required to change the barrel, first, the rubber gasket/breach needs to be drilled or melted out to the appropriate diameter, my method was to simply heat up a .25 cal bearing, then push it through the breach, melting it out to the correct size, this is a simple and brutal method but it did work. Next the muzzle cap, this holds the muzzle end of the barrel in place in the outer barrel, the cap is fitted to the 4.5mm barrel and must be drilled out to accept the new barrel. Now the barrel is ready to insert into the outer barrel shell, fitting the breach gasket, and fitting into the muzzle. A few wraps of teflon tape around the barrel will give a snug fit and ensure the barrel doesnt jettison itself upon firing.
My next step is to order some 3d printed 6mm Umarex shells, which someone over on Thingiverse has done and tested, and they feed reliably according to them. I will then drill those shells out to 6.35mm. After that I will update and give you guys a performance report.
I picked up this fun .177 rifle last year. A handy little lever action and a decent plinker, but I actually primarily wanted it for the mechanism which imitates the real gun with shells that chamber and eject with a wonderful metallic ratcheting. I spend a lot of time loading empty shells, working the lever, and watching them eject and fly all over the place, quite cathartic. It wasn't long, however, that I realized that the unique shell-loading allows for a huge range of ammunition to feed, darts, pellets, bbs, 4.5mm metal rods, anything of the correct diameter and not longer than the shell will work.
To convert this rifle I started by increasing the tension in the hammer spring to give the valve a little harder kick which increases co2 usage and power. This thing runs off of 2 12g co2 bulbs, you get around 90 shots from those 2 bulbs, so even if you double the output you should still get a good number of shots per fill. Then I needed to swap out the barrel. This was a fairly straightforward process as the barrel is just a simple smoothbore and resembles an airsoft barrel. The rifle disassembles beautifully, it takes little more than a minute to bring the gun down to the point where I can pull the barrel, breach, and magazine tube out, the valve, co2 chamber, and lever action linkage can be dropped out in less than 5 minutes once you get familiar with it. You could literally replace valve o-rings in the field so long as you had a screwdriver and pliers.
Anyway, a few dremel mods are required to change the barrel, first, the rubber gasket/breach needs to be drilled or melted out to the appropriate diameter, my method was to simply heat up a .25 cal bearing, then push it through the breach, melting it out to the correct size, this is a simple and brutal method but it did work. Next the muzzle cap, this holds the muzzle end of the barrel in place in the outer barrel, the cap is fitted to the 4.5mm barrel and must be drilled out to accept the new barrel. Now the barrel is ready to insert into the outer barrel shell, fitting the breach gasket, and fitting into the muzzle. A few wraps of teflon tape around the barrel will give a snug fit and ensure the barrel doesnt jettison itself upon firing.
My next step is to order some 3d printed 6mm Umarex shells, which someone over on Thingiverse has done and tested, and they feed reliably according to them. I will then drill those shells out to 6.35mm. After that I will update and give you guys a performance report.
