Targetgunna
Busy member
Hey guys,
My Vulcan gas ram conversion is finished, just sharing what I had to do and how it's worked out so here goes:-
First of all thank you to all that have helped steer me in the right direction, special thanks to Gatman who has actually done the Webley gas ram conversion and gave me some great info.
I've heard nitrogen rams can be a little vicious so I chose the 550n ram designed for a 22 as apposed to the 650n for the 177, I'm glad I did as its pushing out around 11.2 foot pounds, (MBR chrono) I feel it would have been way to close for comfort with the more powerful ram!
Comparing it to my 22 Vulcan, I tried both of them in the shop, I bought the 22 initially to gas ram this but it shot so smooth that I decided to put a tuning kit in it, (11 foot pounds dead on) I have to say, this is the smoothest shooting springer I own, even more than my HW97!! Yep it's true.......accuracy is another thing, obviously pellet choice for proper 22 is limited, Anyway I still had the gas ram conversion on my mind so I went back and bought the 177 Vulcan, wasn't quite as smooth in spring form but pellet choice is huge, incidentally tried 4.51 FTT too loose, velocity all over the place, 4.53 JSBs perfect, haven't done accuracy yet, just finished it, this is just a consistency test.
It cocks very smoothly but then so does the spring version, probably easier towards the end of the stroke.
Shooting it does feel different, I'm trying to put my finger on it, hmm, almost like slightly more initial recoil then a thud then nothing, no slight aftershock (probably not the right word) this is on the bench, standing, it seems incredibly smooth. It feels more like my Anschutz 1813 rim fire, just a little up and down moment then nothing. I like it.
I'm waiting on some steel to arrive to make a 200g barrel weight.
What did I have to do to convert ?
Please see attached pics for mods,
I turned down the spring guide locator just below the pin slot and put a dimple in it for the ram rod to locate, this only gave me about 2.5mm of pre load, too close to the end of the stroke so I found a flanged nut, turned it down on my lathe so it would locate centrally on the old spring guide and the rod, this gave around 6.9mm of preload and matched the stroke of the spring, any longer and it wouldn't cock. Ever so slightly under the 10 percent recommendation for gas ram pre tension but that is all I can get.
I put an O ring at each end of the ram and a layer of electrical tape to locate it centrally for ease of assembly, it probably would have sat nicely when under load without them but as I've said it held everything in place during assembly.
I could not have done this without a spring compressor, bought a sash clamp for Screwfix and stuck 3mm leather from an old leather belt on each end, this holds everything in place without slippage.
The power is spot on at around 11.2 foot pounds, I'm so pleased.
I fired about 10 shots off just settle everything in plac then put 10 shots though the MBR chromo, spread of around 12 fps, which is on par with my tuned HW97.
I also did a restoration on the stock and action, I really didn't like the 'orange' (what were you thinking Webley?) stain that they used, so I stripped it and used dark walnut stain then Danish oil for a lovely satin finish, it is a beech stock but I hit lucky with the grain, just see pics.
The action had a lot of pitting in it so I decide to go back to bare metal and cold blue everything, took some work, starting with 120 grit!!! Yikes!!! in the orbital sander up to 400 then sanding along the length with 400 by hand.
Cold blue was with the Birchwood Gel, it took about 10 coats to get it dark and even, it looks beautiful, not as tough and factory and I got a few scratches in it during the many assembly and disassembly sessikn to get stroke correct but I just cleaned it with acetone and scrubbed more gel into it with a white pan scourer and it matched perfectly, the beauty of cold bluing, just so easy to repair, then gun gun oil on top of this.
I polished the trigger and sear but I have not cut the spring just yet, I want to make sure it is safe with the ram over the next week before doing anything like that.
I cut the spring down on my 22, 2 coils was fine, 3 coils, whoops, nope, had to wind the grub screw in.
Anyway I'll do a follow-up testing trigger pull and accuracy.
Oh and the 22 is a Mk3 and the 177, is a Mk2.
My Vulcan gas ram conversion is finished, just sharing what I had to do and how it's worked out so here goes:-
First of all thank you to all that have helped steer me in the right direction, special thanks to Gatman who has actually done the Webley gas ram conversion and gave me some great info.
I've heard nitrogen rams can be a little vicious so I chose the 550n ram designed for a 22 as apposed to the 650n for the 177, I'm glad I did as its pushing out around 11.2 foot pounds, (MBR chrono) I feel it would have been way to close for comfort with the more powerful ram!
Comparing it to my 22 Vulcan, I tried both of them in the shop, I bought the 22 initially to gas ram this but it shot so smooth that I decided to put a tuning kit in it, (11 foot pounds dead on) I have to say, this is the smoothest shooting springer I own, even more than my HW97!! Yep it's true.......accuracy is another thing, obviously pellet choice for proper 22 is limited, Anyway I still had the gas ram conversion on my mind so I went back and bought the 177 Vulcan, wasn't quite as smooth in spring form but pellet choice is huge, incidentally tried 4.51 FTT too loose, velocity all over the place, 4.53 JSBs perfect, haven't done accuracy yet, just finished it, this is just a consistency test.
It cocks very smoothly but then so does the spring version, probably easier towards the end of the stroke.
Shooting it does feel different, I'm trying to put my finger on it, hmm, almost like slightly more initial recoil then a thud then nothing, no slight aftershock (probably not the right word) this is on the bench, standing, it seems incredibly smooth. It feels more like my Anschutz 1813 rim fire, just a little up and down moment then nothing. I like it.
I'm waiting on some steel to arrive to make a 200g barrel weight.
What did I have to do to convert ?
Please see attached pics for mods,
I turned down the spring guide locator just below the pin slot and put a dimple in it for the ram rod to locate, this only gave me about 2.5mm of pre load, too close to the end of the stroke so I found a flanged nut, turned it down on my lathe so it would locate centrally on the old spring guide and the rod, this gave around 6.9mm of preload and matched the stroke of the spring, any longer and it wouldn't cock. Ever so slightly under the 10 percent recommendation for gas ram pre tension but that is all I can get.
I put an O ring at each end of the ram and a layer of electrical tape to locate it centrally for ease of assembly, it probably would have sat nicely when under load without them but as I've said it held everything in place during assembly.
I could not have done this without a spring compressor, bought a sash clamp for Screwfix and stuck 3mm leather from an old leather belt on each end, this holds everything in place without slippage.
The power is spot on at around 11.2 foot pounds, I'm so pleased.
I fired about 10 shots off just settle everything in plac then put 10 shots though the MBR chromo, spread of around 12 fps, which is on par with my tuned HW97.
I also did a restoration on the stock and action, I really didn't like the 'orange' (what were you thinking Webley?) stain that they used, so I stripped it and used dark walnut stain then Danish oil for a lovely satin finish, it is a beech stock but I hit lucky with the grain, just see pics.
The action had a lot of pitting in it so I decide to go back to bare metal and cold blue everything, took some work, starting with 120 grit!!! Yikes!!! in the orbital sander up to 400 then sanding along the length with 400 by hand.
Cold blue was with the Birchwood Gel, it took about 10 coats to get it dark and even, it looks beautiful, not as tough and factory and I got a few scratches in it during the many assembly and disassembly sessikn to get stroke correct but I just cleaned it with acetone and scrubbed more gel into it with a white pan scourer and it matched perfectly, the beauty of cold bluing, just so easy to repair, then gun gun oil on top of this.
I polished the trigger and sear but I have not cut the spring just yet, I want to make sure it is safe with the ram over the next week before doing anything like that.
I cut the spring down on my 22, 2 coils was fine, 3 coils, whoops, nope, had to wind the grub screw in.
Anyway I'll do a follow-up testing trigger pull and accuracy.
Oh and the 22 is a Mk3 and the 177, is a Mk2.
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