I have two 1917 enfields that are sporterized, both are still cock on close. Searching Numerich Arms, I found a "Cock on Open" assembly but it states that it is for original military trigger only. Both of my rifles have trigger mods. One has a Huber Concept replacement and the other a Timmney.
Has anyone made this conversion and if so, can it be adjusted to work on the Timmney?

Long ago I made a match rifle out of a '17. I used the kit you described and made it work with a TImmney trigger. If I remember right, there was a problem because the Timmney uses a floating sear, and this would not work with the conversion so I had to install a larger sear piviot pin to make it solid. In the end it works fine and I shot many thousands of rounds in that rifle, but with the short (5/16") pin travel I would get misfires if the spring was not fairley new.

Thanks for the reply Doug. So it should work very well on the Huber Concept conversion. Only thing you change is the trigger. Since I really like the Huber I may try this on my .06 and if all goes well, change the Whelen back to original equipment plus the Huber and go from there.
Thanks again.

I tried one of the Numrich converters. as stated the firing pin drop is pretty short. it takes a strong replacement spring to work at all. so much for "easy opening".
good luck!

Firing pin travel (and misfires) have always pleagued the "cock on opening" conversions.

Making fool proof cock on opening involves welding up the bolt notch and entirely reshaping the cam..not an easy job!

Thanks for the reply's. Found the same info
on another site. Well, it was a thought. Will leave well enough alone.

quote:

Originally posted by Duane Wiebe:
Firing pin travel (and misfires) have always pleagued the "cock on opening" conversions.

Making fool proof cock on opening involves welding up the bolt notch and entirely reshaping the cam..not an easy job!

Or

http://forums.accuratereloadin...001081641#6001081641

quote:

Originally posted by Duane Wiebe:
Firing pin travel (and misfires) have always pleagued the "cock on opening" conversions.

Making fool proof cock on opening involves welding up the bolt notch and entirely reshaping the cam..not an easy job!

Duane, I defer to your expertese, but I have used the Dayton Traister conversion unit for years on several of my Enfield based sporters, including the one I took to Africa and which accounted for three elephants, five Cape buffalo and a rhino, without ever having the slightest problem with misfires.

I did have a problem with the Numrich version, however. While reassembling the firing pin unit with the extra powerful spring, the striker got away from me and flew up in my face, breaking the right lens of my glasses and filling my eye with splinters. I managed to remove the larger pieces myself, the called the desk at the BOQ, which called an ambulance, which whisked me first to the sick bay at Quantico and then to Bethesda Naval Hospital, where the last of the splinters were removed with no lasting ill effects on my eye. (This occurred obviously during my Marine Corps days, back in the '60's.)

The Dayton Traister unit is still being manufactured and is available at their web site.
http://www.daytraco.com/

I had to have a new spring put in my 1917 recently, due to misfires, and I wonder if it was because it was cock on open.

I also have wondered, if cock on close wouldn't be better. it now takes a bit more juice to open the bolt and I would like to try an unaltered at some point and see if it isn't easier on the forward and down strokes to operate it.

is there an advantage to cock on open or is it just because so many people are used to it?

Red

What Duane said.

One of my first conversions was a 1917 and I did the welding upcock conversion, following the dimensions shown in the TSJC gunsmithing drawings. Worked perfectly, no problems at all.

Later on other conversions I used the Numrich part and had nothing but problems. Don't know about D-T except that their other replacement parts often appear to be awkwardly shaped and sometimes downright ugly. Don't get me wrong, I've used D-T stuff with perfect satisfaction many times and will use them again, it's just that sometimes there are better-looking alternatives out there.

I recommend that anyone contemplating this conversion first obtain the TSJC drawings and use them to do the welding version. For me, over the years, it has worked out much better than anything else.
Regards, Joe

quote:

Originally posted by Dago Red:
is there an advantage to cock on open or is it just because so many people are used to it?

Red

I think the average hunter who takes the rifle from his shoulder to operate the bolt would never notice the difference between a cock on opening and a cock on closing system.

I know that before World War I British professional soldiers, the "Old Contemptables", could achieve an astonishing rate of fire with their cock on closing SMLE's and I personally have gotten off five aimed shots in eight seconds with such a rifle, starting with a round in the chamber.

However, because I have spent a good bit of my life engaged in competetive high power shooting with a bolt rifle, shooting a course of fire which requires ten shots in 60 seconds, standing to sitting, with reload, at a target 200 yards away with a seven inch ten ring and a three inch "X" ring, iron sights only, my conception of how a bolt rifle should be set up are somewhat different than that of the average hunter.

The difficult act of opening the bolt against the resistance of the fired case, plus the resistance of the mainspring is carried out with the pressure to the rear, into the shooter's shoulder. The relatively easy task of chambering a loaded round from the magazine and locking the action is carried out in the opposite direction.

In one of my .308 match rifles the task of opening the bolt is carried out with my index finger and that of closing the bolt with my thumb. There is no need to grasp the bolt knob.

This method would not work with a cock on closing, which requires a firm grasp of the bolt handle and a vigorous shove forward to chamber the round, cock the action and lock the bolt.

On two occasions I was called upon to exercise my rapid fire technique against African game, both times with my .505. The first time, I emptied my rifle at a charging rhino, turning him with the first shot and adding three more as he retreated. The second time, I had a shot at a buffalo which was running past me from left to right. I put four rounds (magazine capacity) into him, three of which were in his shoulder, in a group which could be covered with a playing card. Both times I was using my Enfield/Dayton Traister conversion unit.

My rifle with the Dayton Traister unit installed. My wildcat .505 cartridge is the one in the middle. 570 grain bullet at 2150 fps. with 90 grains of 4064 in a shortened and necked up .460 Weatherby case.



My bad tempered rhino.



My startled buffalo

Awesome! Sounds like an exhilarating hunt and great shooting.

thank you for the response, having never shot a cock on close rifle I didn't know how much power they took to cock and close.

JD, are those drawings only available at TJSC? I can't do the work but still enjoy seeing the way things are done.

Red

Red, we were issued a little booklet of various drawings done in the TSJC Engineering Drawing classes. This was back in the '60s and I assume that something similar is offered to today's student as well. AFAIK these would be proprietary to the school and so probably wouldn't appear anywhere else, but I'll bet that a call or letter to the TSJC smithing department would net you enough info to order your own copy from the school or one of the students. Mine had plans for lots of cool smithing things such as special taps, bolt forging blocks, various mandrels, various conversions, etc etc. I have no idea what happened to mine, it grew legs and walked off.

Apparently it had taken walking lessons from some of my tools that had disappeared earlier...
Regards, Joe

JD, thanks man, you made me laugh. that class on walking must be taught by my dress socks.

I'd like to get my hands on one, just for reference and knowledge.